介质工作参数对板叠上热量搬移效果影响的研究

Research on effect of medium working parameters on heat transfer on stack

为探究介质工作参数对板叠上热量搬移效果的影响,使用数值模拟与试验探究相结合的方法,以板叠两端温差作为试验目标,以声场振动频率、气体振动幅值和板叠材料等作为影响因素,探索各工况参数之间的最佳组合。结果说明对制冷过程影响最大的因素是板叠材料的导热系数,其次为气体微团的振幅,影响最小的是振动频率,最佳因素水平组合为(A3B4C4),即振动频率为1390 Hz、气体振动幅值为20 mm、板叠材料为石棉。板叠材料的选择是优于其它因素的,振幅的调控仅次于材料的选择,在保证前两因素敏感度取到较好水平情况之下,振动频率可在较大范围内选取,为获得大振幅提供了依据。文中把振幅与频率作为独立因素进行考察,发现频率在很宽范围内变化时,对制冷效果影响不大。正交试验结果提示,可以把激励频率设置在一阶活塞模态频率上,以获得最大振幅,而不考虑频率变化的影响。

In order to explore the influence of medium working parameters on the heat transfer effect on the stack,the method of combining numerical simulation and experimental exploration was used to explore the best combination of various working conditions parameters.The temperature difference between the two ends of the stack was taken as the experimental target,the sound field vibration frequency,gas vibration amplitude and stack material were taken as the influencing factors.The results show that the thermal conductivity of laminated materials is the most important factor affecting the refrigeration process,followed by the amplitude of gas clusters,and the vibration frequency is the least,the best combination of factors is(A3B4C4).The vibration frequency is 1390 Hz,the gas vibration amplitude is 20 mm,stack material is asbestos.The choice of laminated material is superior to than other factors,and the adjustment of amplitude is second only to the choice of material.Under the condition of ensuring the sensitivity of the first two factors to a better level,the vibration frequency can be selected in a larger range,which provides a basis for obtaining a large amplitude.In this paper,the amplitude and frequency are considered as independent factors,and it is found that when the frequency changes in a wide range,it has little effect on the refrigeration effect.The results of the orthogonal experiment indicate that the excitation fre-quency can be set at the first-order piston modal frequency to obtain the maximum amplitude with-out considering the influence of frequency variation.