The Propulsion Effect Caused By Exploding Wire In Water

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.