2. Introduction What is a sonic orifice? How does it work? What are its uses? How is it applicable to lasers?

3. Sonic Orifices Opening to a cavity Reduces flow area to a sonic throat Differential pressure and orifice plates (looks like a donut!) Determines mass flow rate Cross-section of an orifice plate

4. Theory Derive equations to determine area of a sonic orifice with input flow parameters Observation of the molar flow rate Equations can be used for calibrations once an area is determined

5. Research Methods Experimental Set Up Predictions Experimental Implementation Results and Data Analysis

6. Experimental Set Up.055in diameter orifice.040in diameter orifice Orifice AOrifice B

7. Experimental Set Up Nitrogen flow control valves Micromotion Mass Flow Meter

8. Experimental Set Up Pressure gauge with.055in diameter orifice Pressure gauge with.040in diameter orifice

9. Predictions Use area equation to determine theoretical mass flow rate vs. pressure

10. Experiment Run test using Labview and record data Check for hysteresis –Record at ascending pressure –Record at descending pressure Labview Diagnostics

11. Results

13. Orifices and Hybrid Lasers VertiCOIL – What is it? Gas Flow and Orifices Substantial Effects VertiCOIL Diagram

14. Review Theory is upheld for high mass flow rates Useful for VertiCOIL purposes

15. Acknowledgements NASA Illinois Space Grant Consortium The Boeing Company CU Aerospace Darren King and my fellow coworkers at the COIL Lab