Computer modeling of space charge flow in an electrogasdynamic generator

摘要

In an electrogasdynamic (EGD) generator the flow of a neutral mediumcarrying unipolar electrical charges constitutes an electrical current.A model of the charge flow in an EGD generator was constructed for usein a computer program. The program is designed to solve Poisson's andLaplace's equations for both axi symmetric and two-dimensional geometries.Schlieren photographs of the charge cloud were used to determine thecharge cloud profile required by the program. Computer generated predictionsagreed with three known solutions to Poisson's equation.Computer predictions of the effects of space charge flow modificationwere obtained. Space charge flow was modified both by increasing flowspeed and by manipulating the space charge electric field. Experimentally,this was accomplished by increasing flow stagnation pressure and byapplication of 'a separate controllable electric field. Experimentalresults compare favorably with computer predictions. Some measurementswere also made of the mobility range of the charged particles.