气-液耦合双作用行波热声制冷系统数值模拟研究

Numerical Simulation and Analysis of Gas-liquid Coupled Double-acting Thermoacoustic Refrigeration System

为解决传统热声制冷系统因采用气体谐振管导致整机效率较低的问题,本文提出一种新型气-液耦合双作用行波热声制冷系统,通过数值模拟优化了系统结构尺寸,并对其性能进行了数值模拟分析。首先,对三级气-液耦合双作用行波热声制冷系统的声功、压力及体积流幅值等重要参数的沿程分布进行了研究;然后,研究不同级数下系统的声功、热声转换效率等特性参数;最后,对比分析了各级系统的制冷量及COP随压力的变化特性。研究结果表明:在环境温度293 K、加热温度400 K、制冷温度270 K、平均压力1 MPa下,三级系统COP达到0.7,制冷量为0.78 kW,运行频率为13 Hz,系统相对卡诺效率为22.3%。系统级数增加,整机的功率密度提高,当平均压力为10 MPa时,六级系统制冷量达到最大值16.1 kW,COP为0.38。

A novel type of gas-liquid coupled double-acting traveling-wave thermoacoustic refrigeration system is proposed to solve the low efficiency of traditional thermoacoustic refrigeration with a gas resonance tube.The study optimized the size of the system structure and analyzed its performance using numerical simulation.First,the article studied the distribution of important parameters such as sound power,pressure,and volume flow amplitude of a three-stage gas-liquid coupled double-acting traveling wave thermoacoustic refrigeration system.Then,characteristic parameters such as the acoustic power and thermoacoustic conversion efficiency of the system under different levels were investigated.Finally,the cooling power of different stages and COP with pressure were compared and analyzed.The calculation results show that when the ambient temperature is 293 K,heating temperature is 400 K,cooling temperature is 270 K,and mean pressure is 1 MPa,the COP of three-stage system reaches 0.7,the cooling power is 0.78 kW,the operating frequency is 13.8 Hz,and the relative Carnot efficiency of the system is 22.3%.As the number of system stages increases,the power density of the system increases.When the mean pressure is 10 MPa,the cooling power of the six-stage system reaches a maximum value of 16.1 kW,and the COP is 0.38.