A 500 N model engine filled with LO2/GCH4 was designed and manufactured.A series of ignition attempts were performed in it by both head spark plug and body spark plug.Results show that the engine can be ignited but th...A 500 N model engine filled with LO2/GCH4 was designed and manufactured.A series of ignition attempts were performed in it by both head spark plug and body spark plug.Results show that the engine can be ignited but the combustion cannot be sustained when head spark plug applied as the plug tip was set in the gaseous low-velocity zone with thin spray.This is mainly because flame from this zone cannot supply enough ignition energy for the whole chamber.However,reliable ignition and stable combustion can be achieved by body spark plug.As the O/F ratio increases from 2.61 to 3.49,chamber pressure increases from 0.474 to 0.925 MPa and combustion efficiency increases from 57.8%to 95.1%.This is determined by the injector configuration,which cannot produce the sufficiently breakup of the liquid oxygen on the low flow rate case.展开更多
By using the fractal geometry it is possible to calculate the actual AP (Ammonium Perchlorate) surface area and oxidizer-binder interface fractal dimension in the prediction of burning rate of composite solid propella...By using the fractal geometry it is possible to calculate the actual AP (Ammonium Perchlorate) surface area and oxidizer-binder interface fractal dimension in the prediction of burning rate of composite solid propellants. In this investigation, the fractal dimension was determined by a procedure known as the "Box Counting Method". Using this dimension, surface area relations were developed for the rough particles. This method was implemented in the PEM (Petite Ensemble Model) burning rate model. The comparison of burning rates for a typical propellant by the PEM and fractal model shows that the burning rates obtained by using the fractal geometry are slightly less than those obtained by the PEM model.展开更多
基金Project(613239)supported by the National Basic Research Program of China
文摘A 500 N model engine filled with LO2/GCH4 was designed and manufactured.A series of ignition attempts were performed in it by both head spark plug and body spark plug.Results show that the engine can be ignited but the combustion cannot be sustained when head spark plug applied as the plug tip was set in the gaseous low-velocity zone with thin spray.This is mainly because flame from this zone cannot supply enough ignition energy for the whole chamber.However,reliable ignition and stable combustion can be achieved by body spark plug.As the O/F ratio increases from 2.61 to 3.49,chamber pressure increases from 0.474 to 0.925 MPa and combustion efficiency increases from 57.8%to 95.1%.This is determined by the injector configuration,which cannot produce the sufficiently breakup of the liquid oxygen on the low flow rate case.
文摘By using the fractal geometry it is possible to calculate the actual AP (Ammonium Perchlorate) surface area and oxidizer-binder interface fractal dimension in the prediction of burning rate of composite solid propellants. In this investigation, the fractal dimension was determined by a procedure known as the "Box Counting Method". Using this dimension, surface area relations were developed for the rough particles. This method was implemented in the PEM (Petite Ensemble Model) burning rate model. The comparison of burning rates for a typical propellant by the PEM and fractal model shows that the burning rates obtained by using the fractal geometry are slightly less than those obtained by the PEM model.
