مروری بر انواع مختلف صفحه انژکتور متخلخل در سیستم‌های پیشران فضایی؛ مطالعه موردی راندمان احتراق

Todaychr('39')s human life is undeniably dependent on satellites that have being sent to Earthchr('39')s orbit by space carriers. Delivery of any kind of cargo to space must be carried out by carriers, which are designed and optimized for the best energy consumption mood. One of the optimization steps in space carriers engine  is to use porous materials in the engine injector plate. In this paper, applications that utilize porous materials to improve combustion efficiency are reviewed. In this regard, the results of experiments performed by four different porous injector designs, were studied. The first design was a porous injector with five liquid oxygen injection posts, which has been undergone cold and hot tests for optical research.The test results of the porous injectors API68, API80-168 and the improved API68 injector, using two subscale combustion chambers designed and built at the German Space Research Center, were reviewed. Combustion chamber used for the optical tests, was cooled by water and made possibility of taking picture from combustion process. One of the important points, is the reduction in combustion efficiency of the API80-168 injector head, due to  injector head correction to prevent excess oxygen accumulation near the combustion chamber wall. Another important point, is the acoustic damping characteristic of the porous injector plate, which results in more combustion stability compared to the coaxial injector head. However, during some reviewed test runs of API80-168 injector head, strong oscillatory instabilities were observed which caused the engine to automatically shut down. Finally the experimental results of four different porous injector heads with oxidizer transfer tubes, under different fluid flow regimes and Deep throttling was analyzed.