Da’ Fuser Team Turbojet Diffuser Study Progress Report 1 Robby Swoish Mike Vostrizansky Ryan Wiltshire October 27, 2005

Objectives Reduce length by increasing diffusion angle without inducing separation Reduce length by increasing diffusion angle without inducing separation Maximize pressure gain, thereby increasing burn efficiency. Maximize pressure gain, thereby increasing burn efficiency. Maintain uniform flow into combustor allowing for uniform mixing distribution Maintain uniform flow into combustor allowing for uniform mixing distribution

Outline Must create nozzles to provide for flows of Mach 0.3, 0.35, and 0.4 Must create nozzles to provide for flows of Mach 0.3, 0.35, and 0.4 Test original model for separation and efficiency to use as a benchmark Test original model for separation and efficiency to use as a benchmark Modify model Modify model Test modified model for separation and efficiency Test modified model for separation and efficiency

Overview Pressure Taps Divergence Angle Combustor Entrances Yarn for Flow Visualization Entrance from Compressor Two Identical models One Tests Visual Effects, i.e. location of Separation One Measures Pressure Data for Mach calculations

Matching Conditions/ Theoretical Area Ratio’s for quasi 1D flow Computed necessary choke hole area with Computed necessary choke hole area with area-Mach relation: Desired Mach Number Throat Area (mm 2 ) Throat Radius (mm)

Experimental Setup

TEST 1:10/21/2005 Goal: Characterize incoming flow Mach number Goal: Characterize incoming flow Mach number Expected Results: mm radius used; Mach 0.30 expected Expected Results: mm radius used; Mach 0.30 expected Results: Mach 0.07 calculated from pressure measurements Results: Mach 0.07 calculated from pressure measurements

TEST 1: 10/21/2005 Possible Sources of Error: Possible Sources of Error: –Pressure Leaks –Pitot Probe Errors Misalignment Misalignment Plugged Probe Plugged Probe –Inlet Disturbances Follow Up Tests: Follow Up Tests: –Increase choke area until desired Mach number is reached

Investigation Schedule Progress (weeks)

Potential Modifications Boundary Layer Control By: Boundary Layer Control By: –Suction –Blowing –Vanes –Flow Control Rails –High Inlet Turbulence –Other Vortex Generators