AT-01-04-3 -- Effective Lift Characterization of GAX Cycles PDF

Absorption cycle performance has traditionally been characterized in terms of the cycle lift, defined as the difference between the condenser and evaporator temperatures. Two other temperatures that govern the cycle performance are the generator and absorber outlet solution temperatures. When the cycle is powered by high-temperature heat, the generator outlet temperature is pushed to the limits imposed by solution chemistry, stability, and corrosion. The absorber outlet temperature is normally close to the condenser temperature, when both are governed by ambient conditions. Variations in the absorber temperature relative to the condenser tempera-ture will introduce noticeable changes in overall performance, especially for GAX cycles. An effective lift needs to be defined in order to incorporate the influence of the absorber temper-ature. The effective lift concept is developed in this paper and system performance characterization with conventional and effective lifts are compared. Actual system performance data are presented, validating the concept of effective lift.

Units: SI