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应用三种RNG k-ε湍流模型对单孔气体射流冲击流动与换热过程进行了数值仿真计算,与实验结果的比较分析表明:RNG k-ε系列模型能够对射流冲击流动和换热过程进行较为准确的预测。在此基础上,进一步对局部Nu数、平均Nu数分布的分析表明:喷孔直径D对冲击点处Nu的数值大小无明显影响;射流冲击高度H/D对Nu数的分布规律具有明显且复杂的影响,若以平均换热量最大为标准,当H/D在3～5之间时,可在较大面积范围内获得较高的换热系数;Re数仅影响Nu数的大小,对其分布规律影响不大,随着Re数的增大,Nu数迅速增大,在射流冲击点处Nu以及平均Nu数与Re数的0.85次方成正比。
Three kinds of RNG k-ε turbulence model are applied to simulate the impact flow and heat transfer process of single-hole gas jet. Comparing with the experimental results, it is shown that the RNG k-ε model can simulate the jet flow and heat transfer process More accurate forecast. On this basis, further analysis of the distribution of Nu number and average Nu number shows that the diameter of spray hole D has no significant effect on the numerical value of Nu at the impact point; the distribution of Nu number is obvious with jet impact height H / D If the average heat transfer is the maximum, the higher heat transfer coefficient can be obtained over a large area when the H / D is between 3 and 5. The Re number only affects the Nu number, Its distribution has little effect, with the increase of Re number, Nu number increases rapidly. At the impact point of jet, Nu and the average Nu number are proportional to the 0.85 power of Re number.