THE EFFECTS OF WET COMPRESSION WITH FUEL INJECTION AT THE GEOMETRY AND THE DESIGN POINT PERFORMANCE OF AN AXIAL COMPRESSOR

摘要

Over the past few years, an intensive effort has been put forth to reduce gas turbine engine generated pollutants, as well as fuel consumption. The current research team understanding the motives behind this effort, suggests an alternative method of wet compression that of using fuel as a cooling medium. Fundamentally, the method of wet compression with fuel injection is based on the same principles of wet compression incorporating water injection. However, there are some considerable differences between the two approaches. A thorough comparison has been carried out revealing each method's advantages and disadvantages. Following the initial comparison of the two methods, the study goes a step further by investigating the applicability of wet compression incorporating fuel. The investigation has taken into account the characteristics of the axial flow compressor where a typical aviation fuel was injected. However, in order to acquire all the necessary information before putting method's applicability into context, the differences between dry compression and wet compression with fuel injection were examined. In this new approach, the compressor is the engine component where the fuel is injected first, thus a preliminary design study was carried out along an axial compressor's mean radius line. Finally the computation has been carried out for both dry and wet compression techniques. Compressor's specifications were similar to J85's compressor whereas fuel's specifications were based on JP-8's properties. Compressor's geometry and design point performance, were computed using a mean line analysis domestic code. A brief analysis of the code will be given, including both the initial version that was used for the dry compression calculations, as well as the modified one that was used for the wet compression calculations. After that, the presentation of the results follows. Finally, the paper will be concluded with a discussion of the findings and wet compression's with fuel injection perspectives.