间冷式冰箱冷藏室内流场的粒子图像速度场实验研究

Digital Particle Image Velocimetry Measurement of Inner Flow Field in Cooling Chamber of Frost-Free Refrigerator

以一台BCD-190W间冷式冰箱为研究对象,制作了间冷式冰箱透明模型,搭建了冰箱模型中空气流场测量的实验系统.采用数字化粒子图像速度场(DPIV)技术测量了间冷式冰箱模型冷藏室内特征平面区域内的平均速度分布.实验测量结果表明:冷藏室顶层间室内送风口流速最大,底层间室送风口流速略小,而中间两层间室送风口流速低于0.1 m/s,不能满足设计功能要求;各间室内对称的2个送风口流速差别明显,必将导致冰箱间室内温度分布不均匀.实验结果验证了DPIV技术用于测量间冷式冰箱内流场的可行性,揭示了冰箱送风口流速和流量设计中存在的不足,并进一步指明了各间室流量分配的关键在于风道的阻力和流量设计,可为改进冰箱结构和性能提供参考.

A transparent model based on a BCD-190W type frost-free refrigerator was constructed with organic glass, and the experiment system for measuring the air flow characters in the cooling chamber of the model was built. Using digital particle image velocimetry （DPIV） technology, the mean velocities distributions on the typical 2-D zones in the cooling chamber of the model were measured. The experiment results show that the air flow velocities and air flow rates at the supply-air openings were non-uniform. The air flow velocities at the openings in the top chest were the largest in the four chests, and those in the fourth chest were somewhat lower. Moreover, the air velocities at the openings in the second and third chests were less than 0. 1 m/s, and thus the flow rates could not meet the function requirement of the chests. Through the analysis of the velocities distributions, the practicability of using DPIV system to measure the flow characters in the chests of the model were verified, and the shortages of the air velocities and flow rates design were discovered. The measurement results also indicate that the resistance and flow rates design for the air flow ducts are the key factors for the refrigerator design.