大空间竖向热羽流对横向冷射流的干扰作用盐水模拟实验研究

以相似理论为依据,设计搭建了用于模拟大空间建筑室内气流组织的液态模型实验台,对大空间建筑中常见的竖向热羽流对横向冷射流的影响规律进行盐水模拟实验研究。借助速度比例尺解决了冷射流与热羽流系统的相似同步性问题。实验结果表明:在竖向热羽流作用下,横向冷射流的运动轨迹将发生向上的偏转。单股竖向热羽流对单股横向冷射流对作用点上游的冷射流轨迹没有明显干扰作用,冷射流轨迹的抬升主要表现在作用点下游的冷射流末段。在两个热源形成的两股竖向热羽流作用下,单股横向冷射流的运动轨迹发生的偏转量增大;竖向热羽流与横向冷射流的作用点不同,冷射流运动轨迹受到的干扰作用大小也不同,在冷射流初段,冷射流的惯性力作用较强,不易受热羽流干扰,而在冷射流末段,冷射流惯性力减弱,易受热羽流干扰;相对于单股冷射流在两股热羽流作用下的运动来说,两股冷射流叠加后,热羽流的干扰作用有所减弱。

Analysis of Salt-bath Scaled Model on Horizontal Cold Jet Effected by Vertical Thermal Plume in Large Space

Based on the similarity theory, a box containing liquid aimed to model the indoor air distribution in a large space building was constructed, and the liquid experiments were taken to explore the pattern of the effect of the vertical developing plumes on the horizontal jets in large space buildings. The velocity ratio of the model to the prototype was taken to figure out the similarity between the cold jets and the thermal plumes. The results of the experiments show that, under the effect of the vertical developing plumes, the motion curve of the horizontal jets deviated upward. The single plume has little effect on the forepart before the countering point of the plume and jet. The raising of the jet curve is in the terminal of the cold jet. Under the effect of the two plumes, the deviation of a single jet increased. The deviation of the jet curve differs with the countering point of the plumes and the jet changing. In the forepart of the jet, the initial force of the jet predominates, thus the curve is not easy to deviate. However, in the terminal of the jet, the initial force of the jet weakens, and the curve is easy to be disturbed by the plume. Compared with the effect of different plumes, the effect of two plumes on the motion of the single jet weakens after two jets interact.