1. Implementation of Vortex Cavities in a Turbojet Diffuser Sponsor: Williams International Progress Report 5 December 5, 2006 TEAM CRUISE CONTROL Michael Feldman Marvin Kong Nansi Xue

2. Table of Contents Completed Experimental Set-up Testing and Data

3. Completion of Experimental Set-up All preparation work completed Made adapters that connect the pitot /static tubes to the manometers Made pitot and static tubes from the 1/8” copper tubes Glued the PVC pipe to the diffuser adapter

4. Actual Testing SLA models are received on Friday, Dec 2 nd Drilling and attachment of the pitot/static tubes done on the following Monday morning Testing were carried out on Monday and Tuesday

5. Testing Results - Monday Two static pressure taps and one pitot tube at each inlet/ outlet Monday testing done with a flow choker – Inlet Mach number ≈ 0.3

6. Testing Results - Monday Pressure measurements converted to pressure coefficients to evaluate diffuser efficiency 4.7” baseline diffuser has the highest efficiency (Cp = 0.7) 2.7” model with vortex cavity is more efficient than 2.7” baseline, but only slightly

7. Testing Results - Tuesday Flow choker was removed for higher flow speed – Inlet Mach No. ≈ 0.4 Increase in flow speed leads to decrease in diffuser efficiency

8. Testing Results - Monday 4.7” baseline Cp decreased from 0.7 to 0.53 2.7” baseline Cp increased from 0.25 to 0.37 Cp of 2.7” model with vortex cavity decreases only slightly 4.7” baseline model still has the highest efficiency

9. Testing Results - Summary Decreasing diffuser length from 4.7” to 2.7” leads to drastic decrease in efficiency Implementing vortex cavity at low Mach numbers seems to improve diffuser performance, but the effect is minimal. Vortex cavity ceases to be useful at Mach No = 0.34 More analysis to be done and possible errors and improvements in testing to be concluded.

10. Final Cost Increase in cost due to additional soldering equipment, PVC pipe, and pitot tubes

11. Any Questions?