【作者】 张春喜；

【导师】 杨嘉祥；

【作者基本信息】 哈尔滨理工大学 ， 高电压与绝缘技术， 2005， 博士

【摘要】 所谓液电效应是指水等液体介质在高功率脉冲放电作用下产生的声、光、热和机械效应等综合物理现象。自前苏联学者尤特金发现液电效应以来,它已经在工业、科学、医学、军事等方面获得了广泛的应用。本文所开展的研究工作是为了探讨将液电效应用于推进的可能性,其意义在于为实现船舶零速原地回转,避免螺旋桨推进中大回转半径的限制提供一种新的侧推技术。蒸发波模型、动力学模型和经验模型都从不同的侧面描述了爆丝的变化过程,揭示了爆丝材料和周围介质对爆丝断路开关性能的影响。但就如何将爆丝模型用于解释液中放电产生的各种效应还缺乏有效的工作。本文在忽略集肤效应的假设下,用电阻模型分析了爆丝材料和参数对回路放电的影响,给出了描述放电回路的微分方程和求解的初始条件,揭示了放电波形与爆丝尺寸之间的关系,为提高放电速率开辟了新的途径。为了分析液中放电产生的机械力学效应,本文提出了丝爆后气泡的简化动力学模型,利用气泡外压力线性分布的假设,给出了压力波传播的规律。从能量平衡方程出发,在已知能量波形的条件下,对气泡的运动状态进行了研究和模拟,得到了能量动态分配,以及气泡内温度、压力的变化趋势。同时也得到了爆丝参数通过对能量波形的影响而改变气泡运动的过程。建立了由电容储能型高功率脉冲电源、推进加速器和模型推进的控制与测量系统组成的实验模型。根据电解电容器的放电寿命指标以及非振荡放电特点,提出了以电解电容器为储能元件的高效能脉冲电源方案。为避免电容器恒压充电回路的效率限制,给出了用高频软开关技术实现的电容器恒流充电方案,讨论了软开关的工作模式及其约束关系,指出软开关工作于f s < fr/ 2模式是实现恒流充电的理想模式。采用了机械约束和磁约束,构造了独特的放电反应室和电极结构以增强推进效应。设计了轴-径环状结构电极系统和爆丝自动进线装置以及送线检测电路以实现爆丝的连续供给。利用水中丝爆放电实验系统,在不同参数的爆丝样本下,进行了丝爆更多还原

【Abstract】 The so called Liquid-electric Effect is about combined physical phenomena with sound, light, heat and mechanism process caused by high pulsed power discharge in liquid medium such as water. Since the Liquid-electric Effect was found by the scholar Yutkin from former Soviet Union, it has been widely used in many fields such as industry, science, medicine and military affairs. The research work developed in this dissertation is to find a possibility about using Liquid-electric Effect as propulsion. Its significance is that a new lateral thrust technique will be developed to realize shipping turning around at zero speed and to avoid limit of large turning radius in screw propeller propulsion method. Evaporating wave model, dynamic model, and experiential model are all used to describe the exploding wire process from different side. And the influences on wire opening switch properties by the wire material and the surroundings medium are exposed with these models. But there are few works on how to use the wire model to explain every kind of effect caused by discharging in liquid. In this dissertation, with the assumption of neglecting skin effect, the resistance model is put forward to analyze how the discharging result is influenced by the wire material and its parameters. The differential equations and their initial conditions about exploding wire circuit are described. The relationship between discharge current waveform and the dimension of exploding wire is exposed. The calculation results are helpful to search a way to increase the discharge rate and efficiency. For analyzing the mechanics effect caused by discharge in liquid, the simplified dynamics model of the bubble after the wire exploding is put forward. Making use of the assumption of linear distribution about pressure outside the bubble, a regulation for the pressure wave spreading is given. From the equation of energy balance, under the condition of knowing energy dynamic wave infused into wire, the motion state of bubble is simulated. The simulating results about energy dynamic distribution and change trend of temperature and pressure inside bubble are given. The process of bubble motion changed by exploding wire parameter affecting the discharge power waveform is also viewed. An experimental set is established which is consist of capacitor energy storage high pulsed power supply, plasma accelerator and control/measurement system. Considering discharge life limit and non-vibration demand about electrolytic capacitor, a high-performance pulsed power supply project using electrolytic capacitor to store energy is proposed. Aiming at the high charging efficiency, at which the constant voltage charging circuit can’t arrive, a constant current charging scheme for capacitor with the high frequency soft commutation technique is proposed. By discussing soft commutation work modes, an ideal mode to realize constant current charging which needs f s < fr/ 2 is pointed. To enhance propulsion effect, the mechanical restriction and magnetic restriction have been used and a particular discharge reactor with special electrode structure has been constructed. The axial-radial ring electrode system, automatic sending wire set and wire connection detecting circuit are all designed for realizing continuous wire sending. Through experimental system established to test pressure property and propulsion effect of wire explosion in water, the pressure, discharge current, discharge voltage, and propulsion distance caused by wire explosion in water are measured under different wire parameter, different voltage charged in capacitor, and different pressure measurement site. Through analyzing the amplitude character of pressure, the influence of wire parameters and energy in capacitor to pressure wave is discussed and the attenuation character of pressure wave along with the spreading distance is discussed. Through analyzing the amplitude character of pulsed current and voltage, the influence of wire parameters to discharge pulse is found out. The conclusion is that with proper choosing wire parameter and reasonably making use of magnetic restrict and mechanic restrict, the wire explosion process in water can produce strong propulsion effect under driving of capacitor energy stored high pulsed power supply. Theories analysis and experimental research express that the model andmethods proposed in this dissertation has the rationality. It is beneficial to understand the characteristics of the propulsion effect caused by wire explosion in water.更多还原