论文部分内容阅读
本文介绍在高空发射武器时压气机失速和熄火的原因。文中也介绍了一些试验数据。在发射武器过程中,压气机进气道中温度上升可能是影响发动机性能的一个最重要的因素。这一温度的上升是激烈的。由此能说明及分析压气机的失速和熄火。除上述进气道中温度上升的因素外,压气机进气道压力的变化,进气道气流畸变,进入压气机中的可燃物大概也增加了压气机失速的可能性。如果进入发动机进气道的可燃物质一直到进入燃烧室为止,没有燃烧,则其影响是很小的,即其氧气浓度之降低还不足,以影响燃烧室的重要性能。发射武器时,由于压气机主气流量的减小,燃烧室中引起的重大变化是燃料-空气比大大增加。在某些发动机中,这种燃料-空气比的增加在压气机失速前足以引起熄火。然而,对本报告所分析的特殊发动机,压气机失速在熄火前就产生了。缓和在发射武器过程中发动机困难处境的措施包括改变发动机所有的特性几何尺寸,即增加压气机工作点和失速极限之间的安全系数。在发射武器过程中,减少燃料流量也能减少压气机失速的可能性、并且只要不发生失速,将能阻止燃烧室熄火。然而,对此问题最好的解决办法是使武器远离发动机进气道。这样,热燃气就不会进入发动机了。
This article describes the causes of compressor stall and stalling when firing weapons at high altitude. The article also introduced some experimental data. During launch, the temperature rise in the compressor intake may be one of the most important factors affecting engine performance. The temperature rise is intense. This can explain and analyze the compressor stall and stalling. In addition to the above-mentioned temperature rise in the inlet, the change in the compressor inlet pressure, the airflow distortions in the intake duct, and the combustibles entering the compressor may also increase the possibility of compressor stall. If the combustible material entering the air intake of the engine does not burn until it enters the combustion chamber, its effect is very small, ie its oxygen concentration is not reduced enough to affect the important performance of the combustion chamber. When launching a weapon, a significant change in the combustion chamber is a substantial increase in the fuel-to-air ratio due to a decrease in the main gas flow to the compressor. In some engines, this increase in fuel-to-air ratio is sufficient to cause flame stall before the compressor stalls. However, for the particular engine analyzed in this report, the compressor stall occurred before the flameout. Measures to ease the difficult conditions of the engine during launch include changing all of the engine’s characteristic geometries, ie increasing the safety factor between compressor operating point and stalling limit. Reducing fuel flow during launch also reduces the chance of compressor stalls and will stop the flameout of the combustion chamber as long as no stalls occur. However, the best solution to this problem is to keep the weapon away from the engine intake. In this way, hot gas will not enter the engine.