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Abstract In this paper, Linear Regression and M5’Rules models within Data Mining Process and Artificial Neural Network (ANN) model for thermodynamic evaluation of ammonia–water absorption refrigeration systems was carried out. A new formulation based on ANN model is presented for the analysis of ammonia–water absorption refrigeration systems (AWRS) because the optimal result was obtained by using ANN Model. Thermodynamic analysis of the AWRS is very complex because of analytic functions used for calculating the properties of fluid couples and simulation programs. Therefore, it is extremely difficult to perform analysis of this system. COP and f are estimated depending on the temperatures of system component and concentration values. Using the weights obtained from the trained network a new formulation is presented for the calculation of the COP and f; the use of ANN is proliferating with high speed in simulation. The R2-values obtained when unknown data were used to the networks was 0.9996 and 0.9873 for the circulation ratio and COP respectively which is very satisfactory. The use of this new formulation, which can be employed with any programming language or spreadsheet program for the estimation of the circulation ratio and COP of AWRS, as described in this paper, may make the use of dedicated ANN software unnecessary.

Abstract Removing water from various feeds is usually carried out using evaporation process especially in food industry. Due to the high latent heat of water, this unit operation results in consumption of unacceptable amount of energy. Finding low energy consuming processes which could be replaced with this process is still a challenge. The processes with no phase inversion may be considered for concentration purposes with reasonable energy consumption in comparison with the other various separation procedures. Reverse osmosis and most of the other membrane technologies are separation techniques without any change in the phase and therefore consume low amount of energy. Concentrating the sugar thin juice in the classical sugar manufacturing procedure is carried out using conventional evaporation. Reverse osmosis membranes may be used as a pre-concentration step to partially separate water from the sugar thin juice in combination with this part of the plant. Final concentration and thick juice preparation for crystallization may be carried out in the evaporation unit. In this study, membranes were employed for sugar thin juice concentration using a two-stage reverse osmosis process in two different arrangements. The energy consumption was calculated and compared for conventional evaporation versus reverse osmosis combined with evaporation. The results indicate that the employment of revers osmosis membranes for concentrating the sugar thin juice leads to sensibly lower energy requirements. Furthermore, there is no thermal loss of sugar in the membrane process.

Abstract In this paper, a three-dimensional numerical simulation was carried out to characterize a high-ash coal gasification in a pressurized, oxygen-blown, two-stage E-Gas entrained flow gasifier. The Tabas coal was used as a high-ash feedstock, with 32 wt% ash and was compared with the Illinois #6 low-ash coal, with 10 wt% ash. The computational model was conducted in ANSYS FLUENT 14 based on the conservation equations described in the Eulerian–Lagrangian approach. Also, four heterogeneous combined with seven homogeneous reactions were solved via the finite rate and eddy-dissipation/finite rate model, respectively. Two different parametric analyses were conducted to characterize the gasification process in the E-Gas gasifier. These analyses cover the effects of the O2/Coal ratio and coal slurry water content on the gasifier performance characteristics such as the exit temperature, main species mole fractions, carbon conversion, high heating value, yield syngas fraction and cold gas efficiency. It was found that using the higher ash content coal decreases the cold gas efficiency about 5%, limits the gasifier economical operating range, and reduces the exit temperature, yield syngas and total higher heating value.

Abstract The general objective of the investigation described in this article is the experimental testing of solar assisted dryers reported earlier. The tests show good technical results with a conventional energy consumption decrease of 27–80% and an average solar system efficiency of approx. 40%. From the experimental results, it can also be concluded that, with controlled removal of the moist air, improved product quality, significant reduction in drying time and mass losses, etc. result. The introduction of solar dryers seems to be a promising way for drying various agricultural products.

Abstract In this work, the combustion and emission fundamentals of high n-butanol/diesel ratio blend with 40% butanol (i.e., Bu40) in a heavy-duty diesel engine were investigated by experiment and simulation at constant engine speed of 1400 rpm and an IMEP of 1.0 MPa. Additionally, the impact of EGR was evaluated experimentally and compared with neat diesel fuel (i.e., Bu00). The results show that Bu40 has higher cylinder pressure, longer ignition delay, and faster burning rate than Bu00. Compared with Bu00, moreover, Bu40 has higher NOx due to wider combustion high-temperature region, lower soot due to local lower equivalence ratio distribution, and higher CO due to lower gas temperature in the late expansion process. For Bu40, EGR reduces NOx emissions dramatically with no obvious influence on soot. Meanwhile, there is no significant change in HC and CO emissions and indicated thermal efficiency (ITE) with EGR until EGR threshold is reached. When EGR rate exceeds the threshold level, HC and CO emissions increase dramatically, and ITE decreases markedly. Compared with Bu00, the threshold of Bu40 appears at lower EGR rate. Consequently, combining high butanol/diesel ratio blend with medium EGR has the potential to achieve ultra-low NOx and soot emissions simultaneously while maintaining high thermal efficiency level.

Heat transfer and flow characteristics of the sinusoidal-corrugated channel with Al2O3-water nanofluid are analyzed by a 2-D numerical simulation. A parametric study method is used to analyze the performance of sinusoidal-corrugated channel in practical applications like plate-fin compact heat exchangers. The effects of channel height, channel length, wave length, wave amplitude, and phase shift at different Reynolds numbers (6000–22,000) and nanoparticle volume fractions (0–4%) are evaluated. Nusselt number and Darcy friction factor are considered as performance parameters. It is found that the channel height and wave amplitude have the highest influences on Nusselt number and friction factor values, respectively. Also, the results show that the nanofluid flow inside the sinusoidal-corrugated channels offers higher values of Nusselt number compared to the base fluid, while the friction factor of both the nanofluid and the base fluid gets almost the same values. Finally, correlations are proposed to predict Nusselt number and friction factor of the water and Al2O3-water nanofluid flows in the sinusoidal-corrugated channels.

Abstract The neutronic performance parameters, fissile breeding and temperature distribution in the fuel rod are investigated for different coolants (‘He, CO 2 ’, ‘Li 2 BeF 4 ’, ‘Li’, and ‘Li 17 Pb 83 ’) in the fissile fuel breeding zone with volume ratios of V coolant / V fuel , e , (0.5,1,2) under various first wall loads ( P w =2–10 MW m −2 ) in a fusion–fission reactor fueled with ThO 2 . Depending on the type of coolant in the fission zone, first wall loads and volume ratios, fusion power plant operation periods between 1 and 4 years are evaluated to achieve a fissile fuel enrichment quality between 1.2274% and 13.7305% in the above mentioned situation for intervals of half month and by plant factor of 75%. A fusion reactor with (D,T) reaction acts as an external high energetic neutron source. The fissile fuel zone, containing 10 fuel rod rows in the radial direction, covers the cylindrical fusion plasma chamber with 300 cm chamber dimension. At the end of four years, the cumulative fissile fuel enrichment (CFFE) values, indicating rejuvenation performance, increased to 10.184%, 12.218%, 9.650% and 11.089% from 0% in gas, flibe, natural lithium and eutectic lithium coolant blankets with e =0.5 for 10 MW m −2 , respectively, without reaching the melting point of the fuel material. However, for e =1, the CFFE values increased to 10.59% (the best CFFE value for gas coolant), 11.372%, 10.414% (the best CFFE value for natural lithium coolant) and 10.963% from 0% in the above mentioned coolants for 10 MW m −2 , respectively. In the same way, for e =2, the CFFE increased to 10.181%, 13.7305% (the best CFFE value for all coolants), 9.1369% and 11.4809% (the best CFFE value for eutectic lithium coolant) for 10 MW m −2 , respectively. At the beginning of the operation period, for e =0.5, the tritium breeding ratio (TBR) values, being about 0.9092, 0.7075, 0.7921 and 0.9512 for the above mentioned coolants, respectively, at the end of four years increased to 1.2924, 1.1475, 1.0724 and 1.441 (the highest TBR value for all blankets) for 10 MW m −2 . For e =1, these increments are 1.3067, 1.2303, 1.1653 and 1.4033 for 10 MW m −2 . However, for e =2, these values are 1.2256, 0.9993, 0.9341 and 1.4069 for 10 MW m −2 without reaching the melting point of the fuel material. For e =0.5, the blanket energy multiplication ( M ) increases to 2.7349, 2.8045, 2.5685 and 2.8183 (the highest M value for all blankets) for 10 MW m −2 from 2.1534, 2.0251, 2.0918 and 2.0793 in the blankets cooled with gas, flibe, natural lithium and eutectic lithium coolants, respectively, at the end of four years. These increments become 2.6707, 2.7301, 2.4332 and 2.7812 for 10 MW m −2 from 2.1037, 1.8985, 2.004 and 1.9874, respectively, for e =1. However, the blanket energy multiplication ( M ) increases to 2.4122, 2.4573, 2.1413 and 2.3800 for 10 MW m −2 from 2.0196, 1.7323, 1.8658 and 1.8303, respectively, for e =2. The maximum temperatures in the centerline of the fuel rods have not exceeded the melting point of the fuel material for all coolants and e under changing first wall loads between 2 and 10 MW m −2 during the operation periods. While the maximum CFFE values have been obtained in fuel rod row#10 in the gas, natural lithium and eutectic lithium coolant blankets, it has been obtained in fuel rod row#1 in the flibe coolant blanket for all e and P w . Therefore, the investigated hybrid blankets are self-sufficient for all coolant and volume fractions and P w =10 MW m −2 . The best neutron economy has been shown by flibe.

Abstract The technology landscape around distributed generation continues to evolve in response to increasing demand for high-efficiency, low-emission, low-cost power generation. While emerging distributed power technologies, such as solid oxide fuel cells (SOFCs), continue to advance, they still face challenges due to their high capital costs, and shorter lifetimes that typically arise from electrochemical stack performance degradation at high operating temperatures (>750 °C). Recent advancements in protonic ceramic fuel cells (PCFCs) offer the potential to mitigate drawbacks of their higher temperature SOFC counterparts by enabling lower operating temperatures (550 °C–600 °C) with acceptable power densities. The present work leverages the recent progress in protonic ceramic cell and stack technology development to generate viable system configurations and evaluate the energetic performance potential of PCFC-based systems for stationary power generation. Process system engineering of two water-neutral system concepts, which provide 25 kW of electric power and process hot water, are presented and evaluated through sensitivity studies. Stack design parameters are altered and used to gauge the effect on system performance characteristics, including fuel cell stack and balance-of-plant sizing requirements, and electric and cogeneration efficiencies. The study finds that the potentially high per-pass fuel utilization capability of PCFC stacks could enable unprecedented electric efficiencies approaching 70% without hybridization with other prime movers.