Chamber pressure

About: Chamber pressure is a research topic. Over the lifetime, 2988 publications have been published within this topic receiving 30725 citations.

Two-cycle engine

Abstract: PURPOSE:To allow the fuel injection function of a two-cycle engine to operate at optimum efficiency by furnishing a control means to control the injection timing and amount of fuel injection valves arranged on a main and an aux. suction passage. CONSTITUTION:Besides a main suction passage 22 to introduce new air into a crank chamber 21, the two-cycle engine 10 is equipped with an aux. suction passage 30 to introduce new air directly into the crank chamber 21. In this engine 10, No.1 injector 34 and No.2 injector 36 are arranged on these suction passages 22 and 30, respectively. A crank chamber pressure signal from a pressure sensor 50 and signals from a crank sensor 52 and pulser coil 56 are fed into a central processing unit 54, which judges cylinder on the basis of these signals and determines optimum fuel injection timing and injection amount about the injectors 34, 36, and applicable signal is sent. Because the injectors 34, 36 can thus work with optimum injection timing and injection amount through electronical control, effective output can be drawn out of the engine 10.

External air release control in seismic air gun

Abstract: Disclosed is a seismic source device, known in the industry as an air gun, having shuttle and external sliding valve control for allowing a predetermined discharge of compressed air into water for purposes of seismic exploration. The shuttle is controlled by air pressure to move it upward, thereby permitting compressed air in the firing chamber to exhaust through exhaust ports. The external sliding valve had been held in a downward position by air pressure supplied from the firing chamber, compressing a spring. As the firing chamber pressure drops, the compressed spring expands, forcing the sliding valve to move upward, closing the exhaust ports. By preventing further discharge of air, secondary pulses are greatly reduced, with little or no loss in acoustic output, thereby enhancing the operation of the entire system. Further, by preventing all the air in the firing chamber from being discharged, the system becomes more efficient and more cost effective.

Intermittently acting IC engine fuel injection valve

Abstract: A nozzle needle (4) is axially slidable between a stop and open position in the valve housing (9). In the stop position it is pressed against a nozzle needle seat (6) with injection ports (5) by a piston (5). A control chamber (2) is coupled to the valve (1) fuel inlet (7) via one or more closable ducts (14), with the control chamber pressure actuating the piston. Into a valve seat (15) in the control chamber opens an intermediate chamber (12), coupled to the fuel inlet and to the control chamber, which has an outflow port (10) closable by a servo-member (8). In the connecting line between the control and intermediate chambers is located a stop valve for the fuel flow to the control chamber.

Exhaust Gas Analysis of a Vortex Oxidizer Injection Hybrid Rocket Motor

Abstract: Previously a vortex oxidizer injection hybrid rocket motor was developed at the U.S. Naval Academy to investigate possible enhancements to fuel regression rate due to injection method. The motor was developed to operate with a conventional axial injector and a novel vortex injector design using high density polyethylene for fuel and a gaseous oxygen oxidizer. The motor was instrumented with pressure transducers and high-speed gas analyzers to measure exhaust gas carbon dioxide, carbon monoxide, oxygen and unburned hydrocarbons. After multiple tests of both injector configurations measurements for the vortex case indicated fuel regression was more evenly distributed across the fuel grain except at the head end, the average regression rate and chamber pressure were higher and exhaust gas analysis indicated a lower oxidizer-fuel ratio. In order to characterize the rocket chamber and compare with the gas measurements, a rocket chamber simulation was developed. The simulation is a one dimensional Lagrangian combustion analysis developed using Matlab and flame mechanisms available in Cantera, an open source gas/chemical analysis package which included an applicable combustion mechanism for ethylene. The model solves a series coupled ordinary differential equations, which include species balance, energy conservation and conservation of mass. The outputs include species mass fraction, temperature, velocity, density and specific gas constant. The system of equations solved quickly and provided realistic results. Because of low velocities in the chamber, the full kinetics model and equilibrium model differed only slightly. Also comparison with measured carbon dioxide was not consistent with the experimentally determined oxidizer-fuel ratios and requires further study. In this iteration of the model heat transfer were neglected.