中心体空化喷嘴射流实验研究

Experimental study on the waterjet of the central-body cavitation nozzle

为探索中心体空化喷嘴射流的特性,提高射流效率,设计了一种新型中心体空化喷嘴。采用冲蚀靶材的方法,对中心体空化喷嘴射流冲蚀性能进行实验研究,重点分析冲蚀时间、入口压力和靶距对冲蚀性能的影响,并与角形喷嘴、淹没空化喷嘴的射流冲蚀性能进行对比分析。研究结果表明:在相同泵压条件下,中心体空化喷嘴和淹没空化喷嘴的冲蚀能力为角形喷嘴的1.5~2倍,在入口压力小于20 MPa时,中心体空化喷嘴的冲蚀能力比淹没空化喷嘴强,随着压力进一步增大,淹没空化喷嘴冲蚀能力强于中心体空化喷嘴,而中心体空化喷嘴冲蚀能力减弱;在压力较低的情况下,中心体空化喷嘴射流具有更好的集束性;在非淹没情况下,实验所设计的中心体空化喷嘴的最佳靶距范围为2~14 mm。新型中心体空化喷嘴在压力较低情况下冲蚀效果好,适用性强,具有广阔的应用前景。

In order to explore the characteristics of the waterjet of central-body cavitation nozzle and improve the waterjet efficiency,a new type of central-body cavitation nozzle was designed.The waterjet erosion performance of the central-body cavitation nozzle is studied experimentally making use of erosion target,analyse the influence of spray duration,inlet pressure and target distance on the erosion performance.The results are compared with the waterjet erosion performance of angular nozzle and submerged cavitation nozzle.The research shows that the erosion capacity of the central-body cavitation nozzle and the submerged cavitation nozzle is about 1.5~2 times that of the angular nozzle under the same pump pressure condition.When the inlet pressure is less than 20 MPa,the erosion capacity of the center-body nozzle is stronger than that of the submerged cavitation nozzle.With the increasing pressure,the erosion capacity of the submerged cavitation nozzle is stronger than that of the central-body nozzle;at the same time the erosion capacity of the central-body nozzle becomes weaker.Under lower pressure conditions,the central-body nozzle waterjet has better bundling effect.In the non-submerged condition,the optimal target range for the newly-designed central-body nozzle by the laboratory is between 2 mm and 14 mm.The newly designed central-body cavitation nozzle has good erosion performance under lower pressure conditions,has strong applicability,and therefore has broad application prospects.