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Abstract In hot and humid climate such as in Japan and south east Asia, dehumidification in summer is really important for air conditioning. Temperature and humidity independent control (THIC) of air conditioning system can handle sensible heat and latent heat separately, and provide good indoor environment and achieve energy conservation. Desiccant air handling unit is one of the major solution for THIC of air conditioning system. It needs hot water to regenerate sorbent which absorbs moist in the air. Combined heat and power can supply hot water at almost constant temperature for desiccant air handling system and also contribute to the business continuity plan of commercial buildings. However, there are still uncertainties about the factors which affect energy performance of desiccant air handling unit and the optimum design and operations in hot and humid climate. The objectives of this paper are to prove factors which affect energy performance of desiccant air handling unit by measurement analysis and show optimum condition of the desiccant air handling unit under various room conditions by simulation. Measurement analysis shows that energy performance of desiccant air handling unit depends not only on the inlet air condition to dehumidification wheel but also on designed supply air humidity. Furthermore, simulation results show the optimum inlet air condition entering dehumidification wheel under various supply air absolute humidity which is determined by design room conditions. These results provide useful information of desiccant air handling unit during design and operation phase of buildings in hot and humid climate.

The effect of delta 9-tetrahydrocannabinol (delta 9-THC) and alcohol, singly and in combination, on divided attention performance was investigated in cannabis users and non-users who were matched for alcohol use. Both cannabis and alcohol produced decrements in central and peripheral signal detections. Drug and alcohol effects were greater for signal presentations in the periphery. Cannabis users were less impaired in peripheral signal detection than non-users while intoxicated by cannabis and/or alcohol. These findings suggest the development of tolerance and cross-tolerance in regular cannabis users and/or the ability to compensate for intoxication effects.

Abstract Severe accident analysis of a reactor is an important aspect for evaluation of source term. This in turn helps in emergency planning and severe accident management (SAM). Analyses have been carried out for VVER-1000 (V320) reactor following LOCA along with station blackout (SBO) to generate information on these aspects. Availability and unavailability of hydro-accumulators (HAs) are also considered for this study. Integral code ASTEC V1.3 (jointly developed by IRSN, France, and GRS, Germany) is used for analysing the transients. The predictions of different severe accident parameters like vessel rupture time, hydrogen and corium production and radioactivity release to containment have been compared for a spectrum of break sizes to provide information for probabilistic safety analysis (PSA) level-2 and severe accident management (SAM) guidelines.

Abstract This paper deals with a Distribution STATic COMpensator (DSTATCOM) for balancing of source currents, power factor correction and harmonic mitigation in three-phase, three-wire distribution system supplying delta connected load under various source voltage conditions. The control strategy applied to the DSTATCOM play a major role in its performance. A novel approach based on an improved instantaneous active and reactive current component (IARCC) theory is proposed for generation of three-phase reference currents for DSTATCOM. A three-phase voltage source converter with a dc bus capacitor is employed as DSTACOM which will track the reference currents in a hysteresis band scheme. The performance of DSTATCOM is evaluated under sinusoidal, unbalanced sinusoidal and unbalanced distorted source voltage conditions. Variation in load current, variation in magnitude and harmonic content in source voltage has been considered. Delta connected linear as well as non-linear load conditions have been considered. The performance of the DSTATCOM using the proposed control strategy is demonstrated using simulation results in MATLAB/SIMULINK software. Simulation results demonstrate the feasibility of proposed scheme for the control of DSTACOM.

Using both HEM and TEDFM the steady-state behaviour of a rectangular uniform cross section two-phase closed NCL has been studied through one-dimensional approach. Uniform heat flux for heating as well as cooling has been considered along with the constant physical properties, uniform pressure inside the loop and water-steam as the working fluid. For the given operating range and loop geometry, the circulation velocity lies in the turbulent regime. The flow rate monotonically increases with the loop height. However, with heat flux it initially increases, reaches maximum and then falls. This implies that the surface heat flux should match the loop geometry and other operating parameters to produce the maximum flow rate. It has also been observed that the cooling and heating lengths and the temperature of the liquid at the entry of the heating section have to be selected optimally to generate the maximum mass flow rate.

Abstract An experimental study is conducted to investigate the melting and solidification processes of paraffin wax as a phase change material (PCM) in horizontal double pipe heat latent heat storage unit. The present work on phase change process includes study of temperature variations along the axial distances in PCM, determination of heat transfer coefficient as well as the heat flow rate. A series of experiments was conducted to investigate the effect of increasing the inlet temperature and the mass flow rate of the heat transfer fluid (HTF) both on the charging and discharging processes of the PCM. The experimental results show that the PCM melts and solidifies congruently, and the melting front moves from the left to right side of the PCM container whereas the solidification front moves from right to the left along the axial distances in the PCM container. The results indicate that natural convection dominates the melting process in the liquid phase due to buoyancy effects. On the other hand, the solidification process is dominated by conduction. The flow rate and inlet temperature of the HTF in the experiment range has a significant effect on the phase change processes. The results also indicate that the heat transfer coefficient between the HTF and the PCM was affected by the Reynolds number more during the melting process than during the solidification process. Heat flow rate during the melting and solidification process increased by 25% and 11%, respectively, in the case of increase or decrease by 2 °C of the inlet HTF temperature. The results of this study show that by increasing the inlet water temperature from 70 °C to 74 °C, total melting time can be decreased by 31%.