R32制冷剂空气源热泵结除霜特性研究

Study on Frosting and Defrosting Characteristics of Air Source Heat Pumps Using the R32 Refrigerant

R32制冷剂广泛应用于空气源热泵,目前研究主要关注其制冷和制热性能,对结霜特性研究甚少。由于结霜严重影响空气源热泵运行性能,因此本文对采用R32制冷剂空气源热泵抑霜性能和除霜控制性能评价进行了研究。选用不同厂家的5台制冷剂均为R32的空气源热泵,在焓差实验室对不同本构配置(CICO)下机组的结霜性能进行测试,利用制热能力衰减5%的运行时长分析了机组类型、CICO对抑霜性能的影响;并基于制热能力衰减提出了空气源热泵除霜控制性能评价新方法。研究表明:R32制冷剂空气源热泵的抑霜性能与机组类型无关,仅与CICO有关,且呈三次方关系;对于除霜评价,确定制热能力衰减为评价指标,并将“制热能力衰减5%~20%”作为指标范围。本研究对采用R32制冷剂空气源热泵的抑霜性能设计、除霜控制性能评价提供了指导。

The R32 refrigerant is widely used in air source heat pumps,and the current research mainly focuses on its cooling and heating performance,with little research on frosting characteristics.Since frost seriously affects the operating performance of air source heat pumps,this paper investigated the evaluation of anti-frosting performance and defrosting control performance of air source heat pumps using R32 refrigerant.Five air source heat pumps with the R32 refrigerant from different manufacturers were selected and tested to see the frosting performance of the units in an enthalpy difference laboratory under different constitutive configurations(CICO),and the effects of unit types and CICO on the anti-frosting performance were analyzed during an operation duration with 5%heating capacity deterioration.Moreover,the paper also presented a new method of defrosting control performance evaluation of air source heat pumps based on the heating capacity deterioration.The study shows that the anti-frosting performance of air source heat pump using the R32 refrigerant has nothing to do with the unit type,but has a cubic relationship solely with CICO.The heating capacity deterioration is selected as the evaluation index for the defrosting control performance,and its reasonable range is 5%~20%.This study can provide guidance for the design of anti-frosting performance and the evaluation of defrosting control performance of air source heat pumps using the R32 refrigerant.