空调器结霜动态模型建模及实验验证

Dynamic model and validation of air conditioners under frosting conditions

结霜是制约热泵空调系统制热性能及热舒适的最重要因素,开发空调器结霜动态模型是一种优化制冷空调系统控制,提升空调系统能力和热舒适性的一种有效手段。建立了空调器结霜动态模型,首先根据换热器表面的温度计算湿空气掠过换热器后霜层的累积量,然后通过建立霜层累积量和风量的关系从而实现结霜与系统传热传质模型的耦合。实验验证表明,新建的结霜动态模型能够较好的预测结霜工况下风量的衰减和系统的制热量衰减,风量实时最大偏差小于5%,累计制热量计算误差小于5%。

Frosting has the most significant impact on the heating capacity and thermal comfort of heat pump air conditioners. Developing dynamic model of air conditioners under frosting condition is an effective solution to optimize control strategy to improve the heating capacity and thermal comfort of heat pumper air conditioners. A dynamic model of air conditioners under frosting condition is established, where the frost accumulation is calculated by the difference of air humidity through heat exchanger based on the heat exchanger surface temperature at first, and then a relation is built between the frost accumulation and air flow rate to couple the frosting and heat and mass transfer in air conditioning system. The experiment validations show that the new dynamic model can predict the attenuation of air flow rates and the attenuation of heating capacities under the frosting condition, where the maximum real-time deviation of air flow rates are less than 5%, and the calculation error of cumulative heat capacities are less than 5%.