جستجوی مقالات مرتبط با کلیدواژه « ترنسیس » در نشریات گروه « مکانیک »

In this research and for the first time, the performance of hybrid solar-gas turbine power plants modified with humidification-dehumidification (HD) desalination process was simulated with TRNSYS. The system included a 4.6 MW gas turbine, solar tower and HD process with air heater and open cycle for water and air. The results showed that in the hybrid solar-gas turbine power plants, the solar power supplied about the 35-45% of required energy and the amount of fossil fuel consumption was reduced. Also, the emission of CO2 was declined for about 40%. The electric power and efficiency of hybrid system was slightly lower than gas turbine only due to the pressure losses in piping and receiver of solar system. The results of HD desalination indicated that the increase in the temperature and relative humidity of the inlet air increased the amount of fresh water production and increase in the temperature of inlet saline water declined its production. Moreover, the amount of fresh water production had an optimum value respect to the mass flow rate of air and with increasing the air flow, the amount of fresh water production increased and then decreased. In addition, if the mass flow rate ratio of saline water to dry air was equal to 1.8, the gain output ratio (GOR) had a maximum value of 2. Variation of GOR in terms of returned air at different inlet air temperatures was explained.

A solar electric-vapor compression refrigeration (SE-VCR) system has been proposed in this study. The SE-VCR system was investigated for different evaporating temperatures and months in Isfahan city. The system is simulated by software TRNSYS. the hourly cooling load capacities (heat gain) of a sample building during the different days were determined by using meteorological data such as hourly average solar radiations and atmospheric temperatures. The hourly total heat gain of the sample building and the hourly variations of various parameters such as coefficient of the performance, condenser capacity and compressor power consumption were calculated. the minimum photovoltaic panel surface area was determined to meet the compressor power demand according to the hourly average solar radiation data. also the economic calculations were performed for various sizes of solar system and It was found that adding solar system, is economically. also the annual consumption of carbon in the amount of 1241 kg for cooling saves.

Optimal design of combined renewable energy systems for supplying heat load of greenhouses is studied. It is tried to analyze the system technically and economically so that it would be optimal from both viewpoints. Optimal design is done from technical point of view using TRNSYS software by setting different parts of the system so that besides preheating of the fluid entering the evaporator of the heat pump for increasing the temperature, heat recovery of the ground in maximum heat extraction periods and heat recovery during summer time is occurred. The optimized system is then studied from economical point of view and the final optimized design is then selected by trade-off between economical and technical considerations. Selected model has mean seasonal coefficient of performance of 4.14 for heat pump, borehole length of 150 meters and total solar collector area around 9.42 square meters and the temperature of the fluid in ground cycle would increase up to 0.5 or 1 degrees centigrade. Optimal amounts gained are compared with those obtained from and TRNSYS and MATLAB relation. Finally to supply electrical load homer software is used and the optimum system is chosen considering design conditions.

In this study at first، the transient performance of an solar absorption cooling system is simulated for an educational place in Tehran with a 1600 m^2 area by the commercial TRANSYS software including flat plate collector، stratification storage tank، natural gas fired auxiliary boiler، cooling tower، fan coil and etc، then The effects of different parameters such as collector’s area and slope، tank’s volume and auxiliary heater’s set temperature on the system performance from energetic and economic points of view are also studied and in the final step Two-objective optimization of solar absorption cooling system based on the solar fraction and life cycle saving as in objective functions is carried out by means of genetic algorithms and GMDH neural network. Simulation results of cooling system show that the best temperature of heater has to be set as minimum in the operating range. Moreover، with changing in collector area and tank volume simultaneously، it is observed that maximum solar fraction is captured with maximum collector area and maximum tank volume، and also maximum life cycle saving is captured with minimum collector area and minimum tank volume in present range. The final results indicate that the energy and economical performance stand in opposite behavior