Renewable Energy Resources and Technologies
Ahmad Naderi Nobandegani; Mohammad Ahmadzadehtalatapeh
Abstract
In the present study, the performance of a Desiccant Evaporative Cooling System (DECS) under eight different designs to provide the desired indoor air conditions for administration buildings was explored via TRNSYS software. An administration building in Chabahar, Iran as a region with a high cooling ...
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In the present study, the performance of a Desiccant Evaporative Cooling System (DECS) under eight different designs to provide the desired indoor air conditions for administration buildings was explored via TRNSYS software. An administration building in Chabahar, Iran as a region with a high cooling load demand was considered for the study. The simulation results indicated that the two-stage desiccant cooling system (Des. H) was the most suitable design, and it enjoyed the potential to keep the indoor air conditions within the standard recommendations. It was also shown that Des. H is the superior design in terms of energy performance and can meet the space cooling load requirements. The study showed that Des. H had the highest COP value with 2.83. The possible application of solar energy to the regeneration process of the Des. H was also studied. The simulations revealed that Des. H with and without the solar panels had less energy consumption than the existing system. The study showed that the application of Des. H could ensure 26.97 % saving in power per year in comparison to the existing system. Moreover, it was demonstrated that the addition of PVT panels to Des. H could increase the rate of annual power saving to about 68.03 %.
Renewable Energy Resources and Technologies
Mohammad Ahmadzadehtalatapeh; Shahrokh Khaki
Abstract
The application of phase change material (PCM) for energy conservation purposes in the residential buildings was investigated in the present study. Two types of building in terms of materials as the lightweight building (LWB) and heavyweight building (HWB) located in a high cooling load demanding region ...
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The application of phase change material (PCM) for energy conservation purposes in the residential buildings was investigated in the present study. Two types of building in terms of materials as the lightweight building (LWB) and heavyweight building (HWB) located in a high cooling load demanding region of Iran were considered for the study. Different types of PCM from organic and inorganic categories were examined to determine the most appropriate type of the buildings in terms of indoor air conditions and yearly required cooling load. The buildings in the existing form and with an added layer of PCM were simulated hourly, and indoor air conditions and yearly cooling loads were determined. EnergyPlus software was used for this purpose. The study revealed that the LWB with the added layer of calcium chloride hex hydrate (CCH) had the minimum yearly required cooling load with about 39.8 GJ, and 25.7% reduction in the yearly cooling load was observed and the HWB had the best performance in terms of yearly required cooling load with the added n-eicosone (N.EIC) layer with about 28.8 GJ, which is a 47.1% reduction in the yearly cooling load. After determining the proper PCM for the buildings, the recommended PCM was planned to be positioned in the external layer, mid-layer, and internal layer to examine the position effect on the yearly required cooling load
Mohammad Ahmadzadehtalatapeh
Abstract
Air pre-cooling equipment is normally being employed in air-conditioning systems for pre-cooling the ambient outdoor air to enhance the air-conditioning systems performance. In this study, the potential of a passive water-to-air heat pipe based heat exchanger (HPHEX) for air pre-cooling purpose in air-conditioning ...
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Air pre-cooling equipment is normally being employed in air-conditioning systems for pre-cooling the ambient outdoor air to enhance the air-conditioning systems performance. In this study, the potential of a passive water-to-air heat pipe based heat exchanger (HPHEX) for air pre-cooling purpose in air-conditioning systems for the high cooling load demanding regions of Iran was investigated. To this end, effectiveness-NTU approach was employed to determine the thermal performance of the heat exchanger. Water-to-air HPHEX with different numbers of rows namely two, four, and six was studied to determine the heat transfer characteristics of the heat exchanger. The thermal performance of the water-to-air HPHEX was investigated under different operating conditions in terms of evaporator inlet air and condenser inlet water coil face velocities and temperatures. After determining the thermal performance of the water-to-air HPHEX, the air pre-cooling capability of the water-to-air HPHEX was explored hour-by-hour for the required months of the year by using TRNSYS software. Based on the simulations results, the water-to-air HPHEX shows an acceptable thermal performance under the operating conditions. In addition, studies showed that the water-to-air HPHEX has a significant capability for air pre-cooling, which makes it applicable to be implemented in the air-conditioning systems operating in south of Iran.
