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description Publicationkeyboard_double_arrow_right Article , Journal 2010Publisher:Elsevier BV Authors: Nasir M. Mirza; Sana Ullah; Saeed Ehsan Awan; Sikander M. Mirza;Abstract Evaluation of source term has been carried out for the upgraded LEU PARR-I system taken as a typical material test reactor (MTR). The modeling and simulation of release of radioactivity has been carried out by developing a Matlab based computer program which uses the ORIGEN2 code for core inventory calculations. For post 180 full-power days continuous operation, various accident scenarios, with instantaneous release of radioactivity to containment, have been considered including the startup, fuel loading, and loss-of-coolant accidents. For noble gases, iodine and for aerosols, the release rate studies have been carried out for the normal, emergency and for the isolation states of containment. The values of source term as well as that of containment retention factor show rapid increase followed by an approach towards saturation values as the exhaust rate values are increased. The isotope-dependency of the containment retention factor has been studied and the results indicate strong sensitivity for 85 Kr, 137 Xe, 138 Xe and 138 Cs towards exhaust rate values.
Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
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You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2010.08.017&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu17 citations 17 popularity Average influence Top 10% impulse Top 10% Powered by BIP!
more_vert Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2010.08.017&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2007Publisher:Elsevier BV Authors: M. Javed Iqbal; Nasir M. Mirza; Sikander M. Mirza;Abstract Simulations of fission product activity in primary circuits of a typical PWR under flow rate transients have been performed by using a two-stage model for release of fission products from fuel into coolant region. A one-dimensional nodal-scheme has been developed for modeling the behavior of fission products in the primary circuit. For constant-power operation at constant flow rate, results for 15 major fission products show that the activity due to fission products in the primary coolant circuit of PWRs is dominated by 133Xe and it is followed by 135Xe, 131MXe and 129Te which contribute 40%, 12.9%, 11% and 8.2%, respectively, to the total fission product activity. The results of these simulations have been found to agree well with the corresponding values found in ANS-18.1 Standard as well as with some available power-plant operation data. These simulations indicate a strong dependence of saturation values of specific activity on primary coolant flow rate. For pump coastdown having a characteristic time tp ∼ 2000 h, a 8.6% increase has been observed in the value of total specific activity due to fission products. For increasing tp values, the value of maximum specific activity due to fission products shows a rise followed by an approach towards a saturation value.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2007 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2006.10.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu10 citations 10 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2007 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2006.10.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2015Publisher:Elsevier BV Authors: Rubina Nasir; Sikander M. Mirza; Muhammad Kamran Butt; Nasir M. Mirza;Abstract Safety assessment for simultaneous multiple reactivity insertions in a typical research reactor having low enriched, high density (U 3 Si 2 –Al) fuel has been done using modified PARET code. As a first step, the effect of single reactivity ramps on power and temperatures during transients showed good agreement with already published data. Then simulation of transients for multiple reactivity insertions were carried out and the effects on reactor power, net reactivity of the system, and temperatures (fuel, clad and coolant) were studied. The simultaneous reactivity insertions included ramp reactivity (large and small) and beam tube flooding, a ramp reactivity and a core movement and a ramp reactivity and a sample ejection accident respectively. When simultaneously two different reactivity insertion transients are coupled in the reactor under uncontrolled conditions, the self-control of the reactor decreases. The power and temperatures show several peaks and it oscillates along with the net reactivity of the system within the first second of the accident.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2015.07.003&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu5 citations 5 popularity Top 10% influence Average impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2015.07.003&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 1999Publisher:Elsevier BV Authors: Rubina Nasir; Nasir M. Mirza; Sikander M. Mirza;Abstract The sensitivity of various safety parameters, affecting the reactivity insertion limits imposed by clad melting temperature for a typical pool type research reactor, have been investigated in this work. The analysis was done for low enriched uranium (LEU) core with scram disabled conditions. The temperature coefficients of fuel and coolant, void/density coefficient and β eff were individually varied and the reactor behavior for different ramp reactivity transients was studied. In this work ramp reactivity insertions from 1.6 to 2 $/0.5 s were selected and peak power, maximum fuel, clad and coolant temperatures were determined. Results show that peak power decreases with an increase in the Doppler coefficient of reactivity. However, it rises with an increase in the reactivity insertion. Core remains insensitive to the coolant temperature coefficient of reactivity for ramps in the range of 1.6–1.9/0.5 s. Peak power decreases with an increase in the void coefficient of reactivity (0.1 $/%void to 0.8 $/%void). With a decrease in the void coefficient of reactivity, the maximum fuel and clad temperatures show a non-linear rise. Power and temperature peaks in the transient are sensitive to the values of β eff . Finally, it can be concluded that LEU is a safe core due to its smaller β eff , larger Doppler coefficient and void coefficient of reactivity. It is inferred through this work that reactivity insertion limits of LEU core are quite insensitive to β eff , the Doppler coefficient and the coolant temperature coefficient of reactivity. They are highly sensitive to the change of the void coefficient of reactivity in the core.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/s0306-4549(99)00038-9&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu29 citations 29 popularity Top 10% influence Top 10% impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/s0306-4549(99)00038-9&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2010Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Muhammad Rafique; Farooq Ahmad;Abstract A CPAIR code ( Deeba et al., 1999 ) based model has been developed for static and dynamic sensitivity analysis of the corrosion product activity (CPA) in primary circuits of pressurized water reactors (PWRs). This has been implemented in the Matlab program CPAIR-SA and carries out sensitivity analysis of CPA using both static as well as dynamic approaches. For steady state and constant corrosion rate operations, the predicted static value of the normalized sensitivity coefficients have been found in excellent agreement with the corresponding values found by the dynamic analysis. For saturated CPA values, the standard sensitivity coefficients have been found to yield dominant values for re-solution rate coefficients from scale in core and in piping K c , K p as −0.99652, 3.3882 × 10 −3 ; for deposition rate coefficients on core scale and on piping, ɛ c Q c , ɛ p Q p as 0.99798, −8.5652 × 10 −3 ; for removal rate coefficient by ion-exchanger ɛ I Q I as −1.9998; for volume of primary coolant, volume of core scale and volume of piping scale, V w , V c , V p as 1.0018, 0.99652 and −3.3882 × 10 −3 respectively.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2010.04.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu7 citations 7 popularity Average influence Average impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2010.04.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2011Publisher:Elsevier BV Authors: Nasir M. Mirza;add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2011.07.023&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2011.07.023&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2014Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Aneela Zameer;Abstract A comparative study of the Simulated Annealing and Genetic Algorithms based optimization of loading pattern with power profile flattening as the goal, has been carried out using the LEOPARD and MCRAC neutronic codes, for a typical 300 MWe PWR. At high annealing rates, Simulated Annealing exhibited tendency towards premature convergence while at low annealing rates, it failed to converge to global minimum. The new ‘batch composition preserving’ Genetic Algorithms with novel crossover and mutation operators are proposed in this work which, consistent with the earlier findings (Yamamoto, 1997), for small population size, require comparable computational effort to Simulated Annealing with medium annealing rates. However, Genetic Algorithms exhibit stagnation for small population size. A hybrid Genetic Algorithms (Simulated Annealing) scheme is proposed that utilizes inner Simulated Annealing layer for further evolution of population at stagnation point. The hybrid scheme has been found to escape stagnation in bcp Genetic Algorithms and converge to the global minima with about 51% more computational effort for small population sizes.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2013.10.024&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu66 citations 66 popularity Top 1% influence Top 10% impulse Top 10% Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2013.10.024&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2011Publisher:Elsevier BV Authors: Shakeel ur Rehman; Muhammad Siddique; Sikander M. Mirza; Nasir M. Mirza;Abstract GEANT4 – based Monte Carlo simulations have been carried out for the determination of photo-peak efficiency of heavily shielded small high purity germanium detector (HPGe) used for monitoring radiation levels in nuclear power plants. The GEANT4 simulated values of HPGe detector efficiency for point as well as for disk sources, for two different values of collimator diameter, have been found in good agreement with the corresponding published results obtained by using the MCNP code. The work has been extended to study the effect of radial displacement of a source relative to a detector on photo-peak efficiency for both point and disk source, and at various values of γ-ray energies. Also the effect of disk source radius on photo-peak efficiency has been studied. Besides the results of different available physics models in GEANT4 have also been compared. The computed values of efficiency for point as well as for disk sources using the Penelope and Livermore physics models have been found correspondingly consistent for various values of γ-ray energies while some differences (e.g., Penelope model yields 6.3% higher values of photo-peak efficiency for Eγ = 1.332 MeV, 10 mm collimator diameter) have been observed in the corresponding valued obtained by using the Standard physics model.
add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2010.08.010&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu11 citations 11 popularity Average influence Top 10% impulse Top 10% Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2010.08.010&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2012Publisher:Elsevier BV Authors: Nasir M. Mirza; Javaid I. Malik; Sikander M. Mirza;Abstract Extended fuel cycles with 18–24-month duration have complicated effects on primary coolant chemistry and finding optimum pH concentration range is difficult. For extended burnup cycles, study of changes in coolant activity due to corrosion products have been carried out for a typical pressurized water reactor (PWR) under pH and boric acid variations for linearly as well as nonlinearly accelerating corrosion rates. The computer program CPAIR-P ( Deeba et al., 1999 ) has been modified to accommodate for time-dependent corrosion coupled with the effects of coolant chemistry. Results for 24Na, 56Mn, 59Fe, 60Co and 99Mo show that the specific activity in primary loop approaches equilibrium value under normal operating conditions fairly rapidly. During reactor operation, predominant corrosion product activity is due to 56Mn and after shutdown cobalt activity dominates. These simulations suggest that the effect of increase in pH value for an extended 24-month cycle on specific activity in the form of a decrease in the activity smeared by a linearly rising corrosion. The new saturation values for activity at the end of cycle are lower (∼50%) than a reactor operated at constant low pH/natural boric acid in coolant. For linearly accelerated corrosion and an increase in pH value, the coolant activity shows an initial rise and then it falls to a lower saturation level at the end of cycle when pH becomes large and the activity follows the slope of corrosion rate. For nonlinear rise in corrosion rate coupled with the pH rise from 6.9 to 7.4 and use of enriched boric acid (20%–40%) results in coolant activity peak during the cycle and it also approaches much smaller saturation values at the end of cycle when compared with the activity for the system having constant low pH value (6.9) in the coolant. In this paper we show that the use of enriched boric acid as chemical shim actually lowers the primary coolant activity when higher pH values are employed in coolant rather than natural boric acid. For multiple long-term fuel cycles the corrosion product activity shows an initial rise to a maximum value and then it fall back to low saturation values due to high pH concentration for enriched boric acid (40%) as chemical shim. If the removal rates of ion-exchanger are low (eIQI ∼100–300), then the activity builds up. However, when ion-exchanger performs well (eIQI ∼600–900) then the overall cobalt activity remains low and saturation value does not grow much with cycles.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2012 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2012.03.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu9 citations 9 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2012 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2012.03.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2008Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Tariq Asad; Sadaf Waqar;Abstract A comparative study has been performed for neutronic analysis of highly enriched in uranium (HEU) and potential low enriched in uranium (LEU) cores for the Pakistan Research Reactor-2 (PARR-2) taken as a typical miniature neutron source reactor (MNSR) system. The group constant generation has been carried out using transport theory code WIMS-D4 and a detailed five-group RZ-model has been used in the CITATION code for multigroup diffusion theory analysis. The neutronic analysis of the 90% HEU reference and potential LEU alternative: UO 2 , U 3 Si 2 and U9Mo, cores has been carried out yielding 11%, 20.7% and 14.25% enrichments with corresponding values of excess reactivity: 4.33, 4.30 and 4.07 mk. These results have been found in good agreement with recently reported Monte Carlo-based transport theory calculations. The diffusion theory-based calculated values of thermal flux profiles for axial as well as for radial directions have been found to agree well with the corresponding experimental measurements. The UO 2 -based LEU core has been found having flux spectrum closest to the reference core while U9Mo core has significantly harder flux spectrum at irradiation site.
Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2008 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2008.03.016&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu11 citations 11 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2008 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2008.03.016&type=result"></script>'); --> </script>
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description Publicationkeyboard_double_arrow_right Article , Journal 2010Publisher:Elsevier BV Authors: Nasir M. Mirza; Sana Ullah; Saeed Ehsan Awan; Sikander M. Mirza;Abstract Evaluation of source term has been carried out for the upgraded LEU PARR-I system taken as a typical material test reactor (MTR). The modeling and simulation of release of radioactivity has been carried out by developing a Matlab based computer program which uses the ORIGEN2 code for core inventory calculations. For post 180 full-power days continuous operation, various accident scenarios, with instantaneous release of radioactivity to containment, have been considered including the startup, fuel loading, and loss-of-coolant accidents. For noble gases, iodine and for aerosols, the release rate studies have been carried out for the normal, emergency and for the isolation states of containment. The values of source term as well as that of containment retention factor show rapid increase followed by an approach towards saturation values as the exhaust rate values are increased. The isotope-dependency of the containment retention factor has been studied and the results indicate strong sensitivity for 85 Kr, 137 Xe, 138 Xe and 138 Cs towards exhaust rate values.
Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2010.08.017&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu17 citations 17 popularity Average influence Top 10% impulse Top 10% Powered by BIP!
more_vert Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2010.08.017&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2007Publisher:Elsevier BV Authors: M. Javed Iqbal; Nasir M. Mirza; Sikander M. Mirza;Abstract Simulations of fission product activity in primary circuits of a typical PWR under flow rate transients have been performed by using a two-stage model for release of fission products from fuel into coolant region. A one-dimensional nodal-scheme has been developed for modeling the behavior of fission products in the primary circuit. For constant-power operation at constant flow rate, results for 15 major fission products show that the activity due to fission products in the primary coolant circuit of PWRs is dominated by 133Xe and it is followed by 135Xe, 131MXe and 129Te which contribute 40%, 12.9%, 11% and 8.2%, respectively, to the total fission product activity. The results of these simulations have been found to agree well with the corresponding values found in ANS-18.1 Standard as well as with some available power-plant operation data. These simulations indicate a strong dependence of saturation values of specific activity on primary coolant flow rate. For pump coastdown having a characteristic time tp ∼ 2000 h, a 8.6% increase has been observed in the value of total specific activity due to fission products. For increasing tp values, the value of maximum specific activity due to fission products shows a rise followed by an approach towards a saturation value.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2007 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2006.10.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu10 citations 10 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2007 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2006.10.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2015Publisher:Elsevier BV Authors: Rubina Nasir; Sikander M. Mirza; Muhammad Kamran Butt; Nasir M. Mirza;Abstract Safety assessment for simultaneous multiple reactivity insertions in a typical research reactor having low enriched, high density (U 3 Si 2 –Al) fuel has been done using modified PARET code. As a first step, the effect of single reactivity ramps on power and temperatures during transients showed good agreement with already published data. Then simulation of transients for multiple reactivity insertions were carried out and the effects on reactor power, net reactivity of the system, and temperatures (fuel, clad and coolant) were studied. The simultaneous reactivity insertions included ramp reactivity (large and small) and beam tube flooding, a ramp reactivity and a core movement and a ramp reactivity and a sample ejection accident respectively. When simultaneously two different reactivity insertion transients are coupled in the reactor under uncontrolled conditions, the self-control of the reactor decreases. The power and temperatures show several peaks and it oscillates along with the net reactivity of the system within the first second of the accident.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2015.07.003&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu5 citations 5 popularity Top 10% influence Average impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2015.07.003&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 1999Publisher:Elsevier BV Authors: Rubina Nasir; Nasir M. Mirza; Sikander M. Mirza;Abstract The sensitivity of various safety parameters, affecting the reactivity insertion limits imposed by clad melting temperature for a typical pool type research reactor, have been investigated in this work. The analysis was done for low enriched uranium (LEU) core with scram disabled conditions. The temperature coefficients of fuel and coolant, void/density coefficient and β eff were individually varied and the reactor behavior for different ramp reactivity transients was studied. In this work ramp reactivity insertions from 1.6 to 2 $/0.5 s were selected and peak power, maximum fuel, clad and coolant temperatures were determined. Results show that peak power decreases with an increase in the Doppler coefficient of reactivity. However, it rises with an increase in the reactivity insertion. Core remains insensitive to the coolant temperature coefficient of reactivity for ramps in the range of 1.6–1.9/0.5 s. Peak power decreases with an increase in the void coefficient of reactivity (0.1 $/%void to 0.8 $/%void). With a decrease in the void coefficient of reactivity, the maximum fuel and clad temperatures show a non-linear rise. Power and temperature peaks in the transient are sensitive to the values of β eff . Finally, it can be concluded that LEU is a safe core due to its smaller β eff , larger Doppler coefficient and void coefficient of reactivity. It is inferred through this work that reactivity insertion limits of LEU core are quite insensitive to β eff , the Doppler coefficient and the coolant temperature coefficient of reactivity. They are highly sensitive to the change of the void coefficient of reactivity in the core.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/s0306-4549(99)00038-9&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu29 citations 29 popularity Top 10% influence Top 10% impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/s0306-4549(99)00038-9&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2010Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Muhammad Rafique; Farooq Ahmad;Abstract A CPAIR code ( Deeba et al., 1999 ) based model has been developed for static and dynamic sensitivity analysis of the corrosion product activity (CPA) in primary circuits of pressurized water reactors (PWRs). This has been implemented in the Matlab program CPAIR-SA and carries out sensitivity analysis of CPA using both static as well as dynamic approaches. For steady state and constant corrosion rate operations, the predicted static value of the normalized sensitivity coefficients have been found in excellent agreement with the corresponding values found by the dynamic analysis. For saturated CPA values, the standard sensitivity coefficients have been found to yield dominant values for re-solution rate coefficients from scale in core and in piping K c , K p as −0.99652, 3.3882 × 10 −3 ; for deposition rate coefficients on core scale and on piping, ɛ c Q c , ɛ p Q p as 0.99798, −8.5652 × 10 −3 ; for removal rate coefficient by ion-exchanger ɛ I Q I as −1.9998; for volume of primary coolant, volume of core scale and volume of piping scale, V w , V c , V p as 1.0018, 0.99652 and −3.3882 × 10 −3 respectively.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2010.04.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu7 citations 7 popularity Average influence Average impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2010 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2010.04.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2011Publisher:Elsevier BV Authors: Nasir M. Mirza;add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
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For further information contact us at helpdesk@openaire.eu0 citations 0 popularity Average influence Average impulse Average Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2011.07.023&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2014Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Aneela Zameer;Abstract A comparative study of the Simulated Annealing and Genetic Algorithms based optimization of loading pattern with power profile flattening as the goal, has been carried out using the LEOPARD and MCRAC neutronic codes, for a typical 300 MWe PWR. At high annealing rates, Simulated Annealing exhibited tendency towards premature convergence while at low annealing rates, it failed to converge to global minimum. The new ‘batch composition preserving’ Genetic Algorithms with novel crossover and mutation operators are proposed in this work which, consistent with the earlier findings (Yamamoto, 1997), for small population size, require comparable computational effort to Simulated Annealing with medium annealing rates. However, Genetic Algorithms exhibit stagnation for small population size. A hybrid Genetic Algorithms (Simulated Annealing) scheme is proposed that utilizes inner Simulated Annealing layer for further evolution of population at stagnation point. The hybrid scheme has been found to escape stagnation in bcp Genetic Algorithms and converge to the global minima with about 51% more computational effort for small population sizes.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2013.10.024&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu66 citations 66 popularity Top 1% influence Top 10% impulse Top 10% Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2013.10.024&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2011Publisher:Elsevier BV Authors: Shakeel ur Rehman; Muhammad Siddique; Sikander M. Mirza; Nasir M. Mirza;Abstract GEANT4 – based Monte Carlo simulations have been carried out for the determination of photo-peak efficiency of heavily shielded small high purity germanium detector (HPGe) used for monitoring radiation levels in nuclear power plants. The GEANT4 simulated values of HPGe detector efficiency for point as well as for disk sources, for two different values of collimator diameter, have been found in good agreement with the corresponding published results obtained by using the MCNP code. The work has been extended to study the effect of radial displacement of a source relative to a detector on photo-peak efficiency for both point and disk source, and at various values of γ-ray energies. Also the effect of disk source radius on photo-peak efficiency has been studied. Besides the results of different available physics models in GEANT4 have also been compared. The computed values of efficiency for point as well as for disk sources using the Penelope and Livermore physics models have been found correspondingly consistent for various values of γ-ray energies while some differences (e.g., Penelope model yields 6.3% higher values of photo-peak efficiency for Eγ = 1.332 MeV, 10 mm collimator diameter) have been observed in the corresponding valued obtained by using the Standard physics model.
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You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2010.08.010&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu11 citations 11 popularity Average influence Top 10% impulse Top 10% Powered by BIP!
more_vert add ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.anucene.2010.08.010&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2012Publisher:Elsevier BV Authors: Nasir M. Mirza; Javaid I. Malik; Sikander M. Mirza;Abstract Extended fuel cycles with 18–24-month duration have complicated effects on primary coolant chemistry and finding optimum pH concentration range is difficult. For extended burnup cycles, study of changes in coolant activity due to corrosion products have been carried out for a typical pressurized water reactor (PWR) under pH and boric acid variations for linearly as well as nonlinearly accelerating corrosion rates. The computer program CPAIR-P ( Deeba et al., 1999 ) has been modified to accommodate for time-dependent corrosion coupled with the effects of coolant chemistry. Results for 24Na, 56Mn, 59Fe, 60Co and 99Mo show that the specific activity in primary loop approaches equilibrium value under normal operating conditions fairly rapidly. During reactor operation, predominant corrosion product activity is due to 56Mn and after shutdown cobalt activity dominates. These simulations suggest that the effect of increase in pH value for an extended 24-month cycle on specific activity in the form of a decrease in the activity smeared by a linearly rising corrosion. The new saturation values for activity at the end of cycle are lower (∼50%) than a reactor operated at constant low pH/natural boric acid in coolant. For linearly accelerated corrosion and an increase in pH value, the coolant activity shows an initial rise and then it falls to a lower saturation level at the end of cycle when pH becomes large and the activity follows the slope of corrosion rate. For nonlinear rise in corrosion rate coupled with the pH rise from 6.9 to 7.4 and use of enriched boric acid (20%–40%) results in coolant activity peak during the cycle and it also approaches much smaller saturation values at the end of cycle when compared with the activity for the system having constant low pH value (6.9) in the coolant. In this paper we show that the use of enriched boric acid as chemical shim actually lowers the primary coolant activity when higher pH values are employed in coolant rather than natural boric acid. For multiple long-term fuel cycles the corrosion product activity shows an initial rise to a maximum value and then it fall back to low saturation values due to high pH concentration for enriched boric acid (40%) as chemical shim. If the removal rates of ion-exchanger are low (eIQI ∼100–300), then the activity builds up. However, when ion-exchanger performs well (eIQI ∼600–900) then the overall cobalt activity remains low and saturation value does not grow much with cycles.
Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2012 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2012.03.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu9 citations 9 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Progress in Nuclear ... arrow_drop_down Progress in Nuclear EnergyArticle . 2012 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.pnucene.2012.03.001&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eudescription Publicationkeyboard_double_arrow_right Article , Journal 2008Publisher:Elsevier BV Authors: Sikander M. Mirza; Nasir M. Mirza; Tariq Asad; Sadaf Waqar;Abstract A comparative study has been performed for neutronic analysis of highly enriched in uranium (HEU) and potential low enriched in uranium (LEU) cores for the Pakistan Research Reactor-2 (PARR-2) taken as a typical miniature neutron source reactor (MNSR) system. The group constant generation has been carried out using transport theory code WIMS-D4 and a detailed five-group RZ-model has been used in the CITATION code for multigroup diffusion theory analysis. The neutronic analysis of the 90% HEU reference and potential LEU alternative: UO 2 , U 3 Si 2 and U9Mo, cores has been carried out yielding 11%, 20.7% and 14.25% enrichments with corresponding values of excess reactivity: 4.33, 4.30 and 4.07 mk. These results have been found in good agreement with recently reported Monte Carlo-based transport theory calculations. The diffusion theory-based calculated values of thermal flux profiles for axial as well as for radial directions have been found to agree well with the corresponding experimental measurements. The UO 2 -based LEU core has been found having flux spectrum closest to the reference core while U9Mo core has significantly harder flux spectrum at irradiation site.
Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2008 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2008.03.016&type=result"></script>'); --> </script>
For further information contact us at helpdesk@openaire.eu11 citations 11 popularity Average influence Top 10% impulse Average Powered by BIP!
more_vert Nuclear Engineering ... arrow_drop_down Nuclear Engineering and DesignArticle . 2008 . Peer-reviewedLicense: Elsevier TDMData sources: Crossrefadd ClaimPlease grant OpenAIRE to access and update your ORCID works.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.This Research product is the result of merged Research products in OpenAIRE.
You have already added works in your ORCID record related to the merged Research product.All Research productsarrow_drop_down <script type="text/javascript"> <!-- document.write('<div id="oa_widget"></div>'); document.write('<script type="text/javascript" src="https://beta.openaire.eu/index.php?option=com_openaire&view=widget&format=raw&projectId=10.1016/j.nucengdes.2008.03.016&type=result"></script>'); --> </script>
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