Hot water lower limit temperature characteristics of hot water fired absorption chiller using multi-stage absorption

Abstract

The design limits of a hot water fired absorption chiller in a cycle simulation were examined. The authors have already proposed how to determine the lowest limiting value of the smaller of the two temperature differences to get a logarithmic mean temperature difference when designing each element. This new algorithm was applied, based on the trend toward the hot water fired absorption chiller that employs a multi-stage absorption system. After performing a cycle simulation, the effects of stage number for the lowest hot water temperature that could be used in air conditioning were clarified. As a result, it was found that the limits of stage number were existed. It was also found that the lowest limiting temperature of hot water could be theoretically determined in the condition of the infinite-stage absorption system.

Keywords

• absorption refrigerating machine
• refrigeration cycle
• simulation
• heat exchanger
• absorber
• evaporator
• condenser
• generator