Experimental Research On Effect Of Ventilation Parameters On Hydrodynamic Characteristic Of Underwater Vehicle

Ocean will become the main battlefield in the future war. Due to the application oflaunching technology by underwater submarine, the invisibility of submarine isimproved, and the viability of submarine is increased. The way of ventilation onunderwater vehicle shoulder can not only reduce resistance but also improvesurrounding in exiting water process of missiles. By making use of tunnel experiment,the research which is about influence on fluid dynamics of vehicle by ventilationparameters can help to seek out the best ventilation parameters and achieve the besteffect of resistance reduction. During the study of tunnel experiment, cavitation numberis reduced by increasing speed and reducing pressure of working section. Therefore theformation of natural supercavitation is difficult. If we use artificial ventilation approach,it is easier to form supercavitation. This method is used for studying supercavitation bytunnel experiment widely. This thesis’s main research contents are as follows:The underwater vehicle model which is used for tunnel experiment has beendesigned using cone in vitro. By way of active ventilation, with two ventilation slitprovide ventilation for the body and shoulder position of navigation, two ventilationsslit width is adjustable ventilation can also change the angle. Design of ventilationsystem using the control panel consists of flow and gauges pressure, providing fornavigation model in continuous gas to meet the needs of the experiment. The navigationof surface pressure and fluid dynamic design of the measuring device, a model of thebuilt-in pressure sensor was used to measurement of surface pressure of navigation,enable a better arrangement in a model of effective space, making smaller models,improving the accuracy of the experiment by designing. The supporting device of themodel has been improved to make it easier to install and remove the sensor, reduceinstallation errors, improve the accuracy of the experiment. In addition, improving theexperimental programmes, as well as experimental data collection and processingmethods.The experimental research on cavity shape and fluid dynamics characteristics ofunderwater vehicle has been carried out under the condition of single seam ventilation.Changes of cavity shape and fluid dynamics have been analyzed on different ventilationparameters. The law of influence on cavity shape and fluid dynamics characteristics byventilation volume flow rate, ventilation seam width and ventilation angles has beenacquired.The experimental study on cavity shape and fluid dynamics characteristics ofunderwater vehicle has been carried out under the condition of double seams ventilation. Taking advantage of the comparison between single seam and double seams, Changesof vehicle’s cavity shape and force have been analyzed by different seaming situations.