狭缝斜肋内冷通道流动和换热特性的数值研究

Numerical Study on Flow and Heat Transfer Characteristics of Internal Cooling Channel with Slit Inclined Ribs

关键词:  内部冷却  狭缝斜肋  阻力损失  换热特性  数值模拟

Key words:  Internal cooling  Slit inclined rib  Resistance losses  Heat transfer characteristics  Numerical simulation

摘要:

为了探究狭缝斜肋的流动和换热特性，进一步挖掘传统斜肋的性能，采用数值模拟的方法，研究了五种不同位置和倾斜角度的狭缝对45°斜肋流动和换热特性的影响，计算的进口雷诺数为2×10⁴~8×10⁴，并与传统的实心肋进行了对比分析。结果表明，狭缝的存在显著改变了冷却通道的流动结构以及换热分布，降低了冷却通道的阻力损失，减小了通道整体的强化换热系数，但同时增加了肋片表面的强化换热系数，且狭缝的位置和倾斜角度的不同对通道性能也存在一定的影响。对比综合热效率，狭缝斜肋相比实心肋增加了约12%~15%。

Abstract:

In order to investigate the flow and heat transfer characteristics of slit inclined ribs and further improve the performance of traditional inclined ribs, the effects of five kinds of slits with different locations and angles on flow and heat transfer characteristics of 45° inclined ribs were studied by using numerical simulation method. The inlet Reynolds number calculated in this study is ranged from 2×10⁴ to 8×10⁴. A comparison and analysis with traditional solid ribs was conducted. The results show that the slits change the flow structure and heat transfer distribution of cooling channel. The slits decrease the resistance loss and enhanced heat transfer coefficient of cooling channel, but it increases the enhanced heat transfer coefficient of the rib surfaces. On the other hand, the location and the angle of the slits also have some effects on flow and heat transfer performance of cooling channel. The thermal performance factors of the slit inclined ribs increase by 12%~15%, compared with solid ribs.