DYNAMIC SIMULATION OF AN ABSORPTION HEAT-PUMP FOR RECOVERING LOW-GRADE WASTE HEAT

Numerical simulation was carried out to predict the transient operatin g characteristics and performance of an absorption heat pump recoverin g waste heat of 30 degrees C-40 degrees C. The effects of the temperat ure and the mass how rate of the heat transfer medium, the heat transf er area of the system components, and the solution circulation rate on the system performance are investigated in detail. The results obtain ed indicate that a higher heating capacity is obtained with an increas e in driving steam temperature, waste heat temperature, and mass flow rate of hot water and waste water. It is also found that the heating c apacity becomes higher with an increase in heat transfer area of the s ystem components except solution heat exchanger. An increase in soluti on Row rate leads to higher heating capacity but to lower COP. A pract ical absorption heat pump, installed at a chemical plant, was also sim ulated numerically. The simulation results were compared with the oper ation data of the practical system. (C) 1997 Published by Elsevier Sci ence Ltd.