毛细管两级串联节流特性

基于单根绝热毛细管模型建立了绝热毛细管的两级串联节流模型，并根据房间空调器的相关实验数据进行了验证，以两级毛细管的同何尺寸（内径和管长）为变化参数，通过模型对串联节流流量特性进行了仿真和分析，发现了流动壅塞位置的多样性及其对流量的影响，提出了可以指导房间空调器中串联毛细管设计的两点结论：高压连接管只要满足一定的几何尺寸范围就能起到辅助节流的作用；热泵工况下辅毛细管的内径是影响流量的主要参数。

Series Flow Characteristics through Two Adiabatic Capillary Tubes

Based on a general model of single adiabatic capillary tube, the model of series flow through two adiabatic capillary tubes was developed. A simple test of the model was done with the relative experimental data extracted from the experiments of a room air conditioner. With the change of diameters and lengths, the presented model simulates the refrigerant flow rate characteristics through the series capillary tubes. The simulation results show that the flow will be choked at different place when the geometries change. Accordingly, the variation of refrigerant flow rate will be different from that through a single capillary tube. Two useful conclusions are made for the design of series capillary tubes on a room air conditioner: one is that the high pressure connection line will react on the refrigerant flow rate as the secondary capillary tube if its geometries fall into proper range, the other is that the inner diameter of the accessory capillary tube that acts as the first stage capillary tube is the main influence factor of the refrigerant flow rate through the series capillary tubes under the heating mode of a room air conditioner.