| Abstract: | Heat pump dryer characteristics of four configurations, two open and two closed systems, are presented. The results are based on the simulation models developed in Part 1. Emphasis is given to the effects of ambient conditions, recirculating air ratio and evaporator bypass air ratio on the system performance. The criteria for evaluating the system performance are the specific moisture extraction rate (SMER), the moisture extraction rate (MER) and the coefficient of performance (COP). It was found that the ambient conditions and dryer efficiency play an important role in the system behaviour. Optimum performance achieved for one ambient condition cannot be assumed optimum for the others. The recirculating air ratio substantially affects the system performance while the evaporator bypass air ratio shows insignificant effect. © 1997 by John Wiley & Sons, Ltd. |
