为研究燃气轮机排气管道非均匀进口条件下喷雾冷却过程中的管道内部流场、喷雾颗粒汽化运动轨迹和冷却效果影响，基于Realizable k-ε结合壁面函数和DPM模型进行喷雾冷却数值研究，探究在非均匀进口条件下喷雾喷头位置分布的影响和不同喷雾颗粒直径、喷雾流量对管壁和出口降温效果的影响。模型为实际优化后的排气管道模型，排气管道为等直径1.524 m圆柱体，前直段长5 m，后直段8 m，转弯半径2.8 m。喷雾喷射锥角为45°，速度为30 m/s，温度为55℃。研究表明:在非均匀进口条件下，非均匀分布且集中于高温区域的喷头效果最佳，管壁温降为111.08℃，出口温降为97.14℃，而喷头排数对其降温效果影响较小；喷雾冷却前后的出口平面速度分布标准差分别为12.77 m/s和11.14 m/s，喷雾对内部流场有一定影响，改善后直段流场均匀性；非均匀进口条件对直径小于25μm的颗粒影响大，雾滴汽化速度快，无法与壁面碰撞进行充分汽化吸热；随着流量的增大，喷雾对管壁和出口降温效果的影响程度相似，喷雾颗粒的汽化受喷雾流量的影响，流量越大喷雾颗粒汽化长度越长。

In order to study the influence of non-uniform inlet conditions on the internal flow field, evaporation motion trajectory of spray particles, and cooling effect during the spray cooling process in the exhaust pipe of a gas turbine, a spray cooling numerical study based on the Realizable k-ε combined with the wall function and DPM model was conducted. The effects of non-uniform inlet conditions on the distribution of spray nozzle positions, as well as the effects of different spray particle diameters and spray flow rates on the wall and outlet cooling effects, were explored. The model is a realistically optimized exhaust pipe model, with an equal diameter 1.524 m cylindrical pipe, a front straight section of 5 m, a rear straight section of 8 m, and a turning radius of 2.8 m. The spray jet angle is 45°, the velocity is 30 m/s, and the temperature is 55 °C. The study showed that under non-uniform inlet conditions, the best results were obtained with non-uniformly distributed nozzles concentrated in the high temperature region, with a wall temperature drop of 111.08 °C and an outlet temperature drop of 97.14 °C, and the effect of the number of nozzles on the cooling effect was small. The standard deviation of the outlet planar velocity distribution before and after spray cooling was 12.77 m/s and 11.14 m/s, respectively, indicating that spray had a certain impact on the internal flow field and improved the uniformity of the flow field in the straight section. Non-uniform inlet conditions had a greater impact on particles smaller than 25 μm in diameter, with rapid evaporation and insufficient vaporization heat absorption due to insufficient collision with the wall. As the flow rate increased, the effect of spray on the wall and outlet cooling effects was similar, and the vaporization of spray particles was affected by the spray flow rate, with larger flow rates resulting in longer vaporization lengths of spray particles.

国家自然科学基金（52106121）