Transient simulation of ammonia–water mixture desorption for absorption heat pumps

Autor: Alexander Roeder, Anurag Goyal, Srinivas Garimella
Rok vydání: 2019
Předmět:
Zdroj: International Journal of Refrigeration. 100:354-367
ISSN: 0140-7007
DOI: 10.1016/j.ijrefrig.2019.01.032
Popis: Prediction of transient response is crucial to understanding the impact of time-varying operating conditions and the development of field-deployable control systems. A mathematical framework to simulate the transient response of a desorber for small-capacity ammonia–water absorption heat pumps is presented. The model is based on dynamic analysis of conservation equations and accounts for the thermal capacitances in the heat exchanger wall material and fluid volumes. The numerical solver and its implementation are presented. Improved computational performance is achieved by using advanced solvers for stiff differential-algebraic equations. The steady-state predictions of component performance from the model are experimentally validated using a microscale ammonia–water desorber. Transient performance of the desorber in response to changes in the solution flow rate, heat source temperature and ambient conditions is accurately predicted with the effects of mass and thermal energy storage. Transient studies are used to identify control strategies for the desorber component and the overall absorption system.
Databáze: OpenAIRE