【摘要】 采用CD40柴油机油为工作介质,在发动机冷却系统实际工况下,对21种几何尺寸的错列锯齿型不锈钢翅片进行了研究。考察了齿高、齿距、齿开窗宽度、齿厚、齿型角、错齿距对错列锯齿型翅片流动及传热特性的影响,结果表明:在研究参数范围内,齿高为3.2 mm、齿距为14 mm、开窗宽度为1.5 mm、齿型角为70°、齿厚为0.5 mm、错齿距为齿距的1/4时,翅片的综合性能最优。通过仿真数据拟合,得到了基于雷诺数和无量纲参数s/ht、/s、t/b的传热因子、摩擦因子的关联式。70%的传热因子试验值与关联式值的相对偏差在±10%以内;摩擦因子试验值与关联式值的相对偏差在5%~15%,可用于该型翅片的选型和前期设计。更多还原

【Abstract】 With CD40 lubricating oil as work medium,under the engine cooling system work conditions,21 geometrical schemes of stainless steel offset strip fins were studied.The effects of fin height,fin wavelength,fin width,fin angle,fin thickness and staggered fin wavelength on fin heat transfer and friction characteristics were examined.The results indicate that the fin with h=3.2 mm,s=14 mm,b=1.5 mm,α=70°,t=0.5 mm,s0=s/4 shows the more predominant performance.Through the regression analysis of simulated data,the correlations on heat transfer and friction factors were deduced based on Reynolds number and the dimensionless parameters of s/h,t/s and t/b.The relative deviations between the correlation and 70% of experimental heat transfer factors were limited in ±10%,and for friction factors the relative deviations were within 5%~15%.更多还原