Performance study on a diffusion absorption refrigeration heat pipe cycle

This paper describes the thermodynamic analysis of a diffusion absorption refrigeration heat pipe (DARHP) cycle. A computer code was developed for an ammonia–water DARHP cycle with helium as the auxiliary inert gas using EES software. In order to obtain characteristics of the DARHP system, the mass and the energy conservation equations were attributed for each component of the cycle. Also the second law efficiency was examined parametrically by the computer simulation. The model was validated by comparison with previously published experimental data for DARHP system. The cycle performance results under different conditions indicated that the best performance was obtained for the concentration rich solution of 0.35 ammonia mass fraction and the concentration of weak solution about 0.1. The results showed that the exergy losses in the evaporator, condenser and dephlegmator were small. Also the second law efficiency increases with increasing evaporator temperature; and decreases with increasing thermosyphon temperature.