THE ORETICAL ANALYSIS ON THE PERFORMANCE OF BRANCHED GAX CHILLER CYCLE

الملخص

In this study, a branched GAX absorption cycle operating with NH3-H2O pair has been
investigated to assess its performance under steady state conditions. The cycle modeling is
implemented using Engineering Equation Solver (EES) software. Analysis includes
equations of mass, species and energy conservation. The analysis is used to simulate a GAX
absorption chiller utilization for air conditioning applications with a nominal capacity of 95
TR. This chiller uses solar collectors as heat source. The operating parameters are selected at
different values of the heat source temperature (140 - 185°C), condenser exit temperature
(30 to 48°C), evaporator exit temperature (2 to 11°C) ; split ratio (0 to 0.18); the difference in
ammonia concentration(0.25-036), mass flow rate in solution pump mr=1 kg/s; heat
exchanger effectiveness ? ? 0.8. The results showed that the average COP is sensitive to
operating conditions where the average COP and cooling capacity of the branched GAX
absorption chiller increase with increasing generator and evaporator temperature whereas
they decrease with increasing condenser temperature. Simulation results also show that the
split ratio and ammonia concentration difference have a significant impact on the
performance of absorption chiller.