System and method for controlling electric fields in electro-hydrodynamic applications

Abstract

An electro-hydrodynamic system that extracts energy from a gas stream, which includes an injector that injects a first species of particles having the same polarity into the gas stream, wherein particle movement with the gas stream is opposed by a first electric field; an electric field generator that generates a second electric field opposing the first, such that the net electric field at a predetermined distance downstream from the injector is approximately zero; an upstream collector that collects a second species of particles having a polarity opposite the first particle species; a downstream collector that collects the charged particle; and a load coupled between the downstream collector and the upstream collector, wherein the load converts the kinetic energy of the gas stream into electric power.

We claim: 
     
         1 . An electro-hydrodynamic system that extracts energy from a gas stream, the system including:
 an injector that injects a first species of particles having the same polarity into the gas stream, wherein particle movement with the gas stream is opposed by a first electric field;   an electric field generator that generates a second electric field opposing the first, such that the net electric field at a predetermined distance downstream from the injector is approximately zero;   an upstream collector that collects a second species of particles having a polarity opposite the first particle species;   a downstream collector that collects the charged particle; and   a load coupled between the downstream collector and the upstream collector, wherein the load converts the kinetic energy of the gas stream into electric power.   
     
     
         2 . The system of  claim 1 , wherein the first species of particles are injected from an injector exit, wherein a portion of the electric field generator is positioned upstream from the injector exit. 
     
     
         3 . The system of  claim 2 , wherein the electric field generator at least partially encircles the injector. 
     
     
         4 . An electro-hydrodynamic system that extracts energy from a gas stream, the system including:
 an injector that injects a first species of particles having the same polarity into the gas stream, wherein particle movement with the gas stream is opposed by a first electric field;   an electric field generator that generates a second electric field opposing the first, wherein the second electric field reverses the net electric field a predetermined distance downstream from the injector, the second electric field having a higher strength at a point distal from the electric field generator than a point proximal to the electric field generator;   an upstream collector that collects a second species of particles having a polarity opposite the first particle species;   a downstream collector that collects the charged particle; and   a load coupled between the downstream collector and the upstream collector, wherein the load converts the kinetic energy of the gas stream into electric power.   
     
     
         5 . The system of  claim 4 , wherein the electric field generator is an electrode. 
     
     
         6 . The system of  claim 5 , wherein a portion of the electric field generator is positioned upstream from the injector.