结霜工况下热泵空调器性能的数值模拟

Numerical Simulation on the Performance of Heat Pumps under Frost Conditions

本文对热泵空调器在结霜工况下的运行性能进行了理论模拟，建立了热泵空调器制冷系统稳态分布参数模型和结霜过程的动态分布参数模型。在系统模型建立中把结霜过程视为准稳态过程。计算结果表明在霜刚开始形成时，有助于增大管壁和空气之间的换热系数，当霜层达到一定厚度时热泵的制热能力，性能系数等迅速下降。经与其他已发表的文献比较计算结果合理。

In this paper a numerical simulation of the effects of frost growth on the performance of air source heat pumps has been conducted. A general distributed parameter model is presented to describe both steady refrigeration system and dynamic frost process behaviors of heat pump.The process of frost accumulation is considered as a quasi - dynamic process. The results indicates that the frost accumulation on the surface is beneficial to the performance of system because of increasing of heat transfer coefficient between air and heat transfer surface, while frost is thick enough, the heating capacity, coefficient of performance （COP） of heat pump and air quantity of fan reduce rapidly. The model is proved to be feasible by comparing with the experimental and simulation results of published references.