Vendetta Final Proposal Part 1 (3.4 MB) - Cal Poly

6.2 InletsInlet sizing for supercruise at Mach 1.6 restricted inlet choices to a one, two or three shock inlet. Figure 6.4demonstrates shock relationship to Mach number. A pitot inlet is good up until about 1.6 Mach and it is by far thecheapest inlet possible. However, the performance of the inlet above Mach 1.6 is very poor. The pressure recovery of atwo shock inlet (one oblique and one normal shock) and a three shock inlet were analyzed.Figure 6.4 - Shock Angles for Design Mach Number -Mattingly, Heiser and Daley Aircraft Engine DesignAs can be seen, there is a lower cost associated with a two shock inlet. More shocks drive the inlet to be larger,longer, and send multiple radar returns. The above traits do not show enough of a benefit to go with a three shock inlettherefore a two shock inlet was chosen.The optimum deflection angle for Mach 1.6 flow was found for a two shock inlet by finding the stagnationpressure loss across the oblique and normal shock for different deflection angles. The results were graphed in Figure 6.5and the resulting deflection angle for the greatest pressure recovery was found to be 10.75 degrees yielding a pressurerecovery of 97.65%.31