【作者】 贾三春；

【导师】 张东速；

【作者基本信息】 安徽理工大学 ， 机械制造及其自动化， 2009， 硕士

【摘要】 旋转射流是指喷嘴不旋转的条件下产生的具有三维速度、射流质点沿螺旋线轨迹运动而形成的扩散式射流,是自由射流加旋转的一种复合流动,其流动情形较为复杂,大多处于紊流状态。旋转射流清除浅埋地雷表土是利用水射流排雷的一种技术方法,该技术的研究与应用不仅提高了排雷效率,而且进一步拓宽了水射流的应用范围。目前排雷的方法主要有:电磁排雷、雷达排雷、新型声学排雷以及火箭推进排雷等。水射流排雷技术是新近兴起的一种排雷方法,目前还处在探索阶段,缺乏系统的理论及应用研究,本文依托理论分析与实验室模拟试验,从结构设计、破土理论、试验分析几个方面对其进行深入细致的研究。利用高压水射流技术进行探、排雷具以下显著特点:水介质传输方便,便于实现远距离和野外作业;在工作过程中喷头与靶件处于非接触状态,因而便于实现光控、数控或机械手控制;工作过程中不会产生高温、火花、粉尘,不改变材料的力学、物理和化学性能,是目前唯一的一种冷加工手段。由此可见,高压水射流技术尤其适合在易燃易爆的危险环境中进行作业。基于旋转水射流理论和土力学理论,分析了射流对土体表面的作用力以及旋转射流破土机理,认为射流的作用压力是土体发生破坏的最根本的外在因素,而土体的临界破坏力是由其内在因素即土体的物理力学性质决定的,只有当射流的作用力大于土体的临界破坏力,土体才可能发生破坏。建立了模拟试验系统,试验结果表明,提高旋转射流破土效果必须增大射流功率,提高射流压力对破土的效果提高是很明显的。靶距的选择与破土效果的关系也能通过试验确定。本文对旋转射流的运动规律和破土机理进行分析,致力提高其在排雷方面的应用,是一门非常重要的课题。采用理论和试验相结合的方式,对水射流排雷进行系统的探讨,这对探索新的排雷技术和方法显得非常有理论和实际意义。更多还原

【Abstract】 Revolving jet flow is proliferation type jet flow that forms under the condition which the spray nozzle does not revolve with the three dimensional speed, jet flow particle alongs spiral line path movement,and it is one kind of compound flowing of the open jet adding revolving, its flowing situation is more complex, mostly is at the turbulent state. The revolving jet is atechnique method of using the water to eliminate shallow submersion land mine surface, this technology research and the application not only raise efficiency of the mine clearance, but also further expand application scope of the water jet .At present, the main method of removing mines as follow: electromagnetism mine clearance, radar mine clearance, new acoustics mine clearance as well as rocket propulsion mine clearance and so on. The water jet flow mine clearance technology is one mine clearance method which recently emerged, presently, it is still in the exploratory phase and lack of systematic theoretical and applied research. This article depends on the theoretical analysis and the laboratory simulation experiment, carefully research on the structural design, breaking ground the theory and the experiment analysis.By using of the high-pressured water fluid technology exploration, the mine clearance has the outstanding feature: First, the aqueous medium transmission convenience, which is advantageous of realizing the long-distance range and the field work. Second ,the nozzle and the target are at the non-contact condition in the work process, thus is advantageously realizes the light to control, the numerical control or the manipulator control; Third, it will not have the high temperature, the spark, the dust, and will not change the material mechanics, physics and the chemical properties during the work process, so, it is the only one of cold finishing method at present . Thus it can be seen, the high-pressured water fluid technology suits especially in the flammable explosive dangerous environment carries on the work.Based on the revolving water jet flow theory and soil mechanics theory, by means of the action of the jet flow to the soil body surface and the mechanism of the revolving jet flow breaking ground analysis ,and the thoughts of which the action pressure of jetting is basic external factor of the soil body destruction, but the soil body critical destructive power to soil body is determined by its internal factors that physical and mechanical properties of the soil, only then, when the jet flow action is greater than the soil body the critical destructive power, the soil body only then possibly has the destruction. Established indoor has simulated the test platform, the test result indicated that enhanced the revolving jet flow to break ground the effect to increase the jet flow power,and enhanced the jet pressure to the effect enhancement which broke ground is very obvious. The target is apart from the choice to breaks ground the effect relations ,also to be able through the experimental determination.By means of the revolving jet flow’s law of motion and breaking ground the mechanism analysis of the article , using a combination way of the theory and the experiment to systematically discuss the new water jet flow mine clearance technology ,and it has very important the theory and the practical significance in exploring the new mine clearance technology and the method.更多还原