活塞内冷油腔两相流振荡可视化模拟

设计并搭建一个活塞振荡两相流可视化模拟试验台，利用3D打印技术还原某型号柴油机的活塞内冷油腔，针对甘油水溶液以及大豆油2种不同的冷却介质，在可视化拍摄流场图像的同时，收集出油数据并计算通过率. 研究发现，所采用的试验方法可摒弃喷油飞溅干扰，准确采集出油量数据，获得了清晰可辨的可视化图像. 将拍摄结果进行对比分析，并对两相流振荡的流型进行辨识和分类，发现当雷诺数达到20 000以上时，两相流振荡的流动状态会发生明显变化，流动进入强湍流状态.

Visual simulation of two-phase flow oscillating flow in piston cooling gallery

The experimental platform for two-phase flow oscillating flow visualization experiment was designed and established, by using 3D printing technology to restore the cooling gallery in a certain type of diesel engine piston. For the two different cooling media, glycerin aqueous solution and soybean oil, oil output data was collected and the oil pass rate was calculated while the flow field images were taken visually. The oil data was collected and the pass rate was calculated while taking visual image of flow field for two different fluid medium. Results show that the proposed test method can abandon the spray splash interference, collect the oil output data, obtain a clear and identifiable visual image. The photographic results were compared and analyzed, and the flow patterns of two-phase flow oscillating flow were identified and classified. As results, when the Reynolds number is above 20 000, the flow state of the two-phase flow oscillating flow changes significantly and enter strong turbulent state.