基于等焓和等温过程的热泵烤烟系统性能的理论分析与比较

Theoretical analysis and comparison of performance on heat pump system for flue-cured tobacco based on isenthalpic and isothermal process

为了研究不同干燥过程对热泵烤烟系统性能的影响,该文对基于等焓和等温过程的新型热泵烤烟系统的应用性能进行了理论分析与比较。在给出该系统设计参数和烤烟工艺模式的基础上,鲜烟量为3000kg时,分析得到等焓和等温过程中烤房所需最大热负荷均为37.05kW,在烤烟整个阶段,等温过程的制热系数均高于等焓过程的制热系数,且等温比等焓过程的系统平均除湿能耗比大0.13kg/(kW·h)。研究结果还表明得到1kg干烟,等温比等焓过程的热泵系统的烘烤成本降低了0.06元,节省总烘烤成本28.86元。因此等温过程的热泵烤烟系统性能高于等焓过程的热泵烤烟系统性能。

In order to investigate the effects of different drying processes on properties of heat pump system for curing tobacco, the application performance of a novel heat pump system for tobacco leaf flue-curing was analyzed and compared based on isenthalpic and isothermal process. On the basis of given system design parameters and tobacco curing process, the maximum heat load in barn was 37.05 kW both during isenthalpic and isothermal processes when the quantity of fresh tobacco loaded was 3 000 kg. The coefficient of performance （COP） during isothermal process was higher than that during isenthalpic process throughout the periods of curing tobacco. The average specific moisture extraction rate （SMER） throughout isothermal process was 0.13 kg/（kW.h） higher than that throughout isenthalpic process. Moreover it could be concluded that the curing cost with heat pump system in isothermal processes was reduced 0.06 Yuan per 1 kg dry tobacco leaves than that in isenthalpic process, totally saving 28.86 Yuan by 481 kg dry tobacco leaves. Therefore, the heat pump system for tobacco leaf flue-curing in isothermal process has better performance than those in isenthalpic process.