Wall Static Pressure Variation in Sudden Expansion in Flow Through De Laval Nozzles at Mach 1.74 And 2.23: A Fuzzy Logic Approach

Abstract

In this paper the analysis of wall static pressure variation has been done with fuzzy logic approach to have smooth flow in the duct. Here there are three area ratio choosen for the enlarged duct, 2.89, 6.00 and 10.00. The primary pressure ratio is taken as 2.65 and cavity aspect ratio is taken as 1 and 2. The study is analysed for length to diameter ratio of 1,2,4 and 6. The nozzles used are De Laval type and with a Mach number of 1.74 and 2.23. The analysis based on fuzzy logic theory indicates that the length to diameter ratio of 1 is sufficient for smooth flow development if only the basis of wall static pressure variations is considered. Although these results are not consistent with the earlier findings but this opens another method through which one can analyse this flow. This result can be attributed to the fact that the flow coming out from these nozzles are parallel one.