Final results from the 2018-2019 Cold-gas Nozzle capstone

1. Creating Uniform Flow with Plenum Implementation for Nuclear Thermal Propulsion Testing
Nathan Fiorino, Michael Boazzo, Aaron King, David Evert, Cullen Willet, Christian Soldat
INTRODUCTION
FINAL DESIGN
• Material of the Plenum changed from Metal to clear PVC
so the team can get a better visual of inside the plenum
• Test Nozzle was made out of metal due to the
respective surface area and pressure loads
• Other than a minor change in the shape of the diffuser
and changing some of the materials, the design more-
or-less remained the same
• In ‘17-’18, an Experimental Capstone Team built an
experimental apparatus for nozzle testing.
• Aimed to get valuable data with regards to Nuclear
Thermal Propulsion (NTP) for a company called BWXT
• Successfully demonstrated the capability of using basic
parts to build a platform to test different nozzle designs
• But the initial design suffered from several limitations due
to unsteady/non-uniform flow
• Results gathered didn’t have much significance in terms of
real analysis
• The Focus was to improve the experimental apparatus’
flow uniformity by integrating a plenum
HYPOTHESIS
A plenum chamber with screens and honeycomb can create
uniform conditions such that the flow’s total pressure at a
point along the radial direction is within 1.34 psi of the radial
average and that point’s peak fluctuations over time do not
increase beyond 0.43 psi between two adjacent points in
time.**
OBJECTIVE
Improve the testability of different nozzle geometries by
reducing total pressure loss and fluctuation of flow entering
nozzles with the addition of a plenum chamber with screens
and honeycomb.
COMPUTATIONAL MODELS
• Built three 2-D models of the plenum in SOLIDWORKS
• The models varied by diffuser length:
• 6 inch, 8.5 inch, 11 inch
• Analyzed the various designs in ANSYS Fluent
• Results showed diffuser could not be less than 11 inches
• Sized plenum using general fluids equations and guidance
of research papers/ advisors
• Modeled in SOLIDWORKS and analyzed in ANSYS Fluent
• Validated current design
• Velocity <= 5 m/s
• Static Pressure >= 45 psi
• Total Pressure = constant
RESULTS
• The pressure threshold with regards to time was
satisfied with regards to time (0.43 psi, at 0.08 psi. )
• Threshold with regards to uniformity in the radial
direction was just outside the desired margins ( 1.34 psi,
at 2.56 psi)
• Need to investigate impact of leaks ⇒ Could be good or
bad
• Overall the hypothesis was not strictly met, but
objectives and success criteria were
FUTURE IMPROVEMENTS
• Vacuum Chamber
• Dehumidifier
• Larger Tank
• Leakage Suppression
• Switch Propellant from Air to Helium
ACKNOWLEDGEMENTS
The Team would like to thank the following people for their
contribution of expertise and resources to the success of
this project.
Dr. John Horack
Mr. Nick Salamon
Dr. Cliff Whitfield
Dr. Nathan Webb
Mr. Kevin Wolf
Dr. Edward Herderick
Buckeye Space Launch Initiative
.
BIBLIOGRAPHY
[1] Nicholas Salamon. (2018). "Cold Gas Nozzle Testing for Aerospace Education.",
2018 Joint Propulsion Conference, AIAA Propulsion and Energy Forum, (AIAA 2018-
5036).
[2] Mazumdar, A. (2018). “Principles and Techniques of Schlieren Imaging Systems.”
Manuscript submitted for publication, Columbia University, New York City. [Online].
Available at: https://mice.cs.columbia.edu/getTechreport.php?techreportID=1542.
[3] Anderson, John David. (2012). Modern Compressible Flow: with Historical
Perspective. 3rd ed., McGraw-Hill.
[4] Matsumoto, J. (2000). “Design and Testing of a Subscale Supersonic
Aeropropulsion Wind Tunnel.” M.S. thesis. University of Texas. [Online]. Available at:
http://arc.uta.edu/publications/td_files/matsumoto-joji.pdf.
[5] Farokhi, Saeed. (2014). Aircraft Propulsion. 2nd ed., John Wiley & Sons. [Online].
Available at: https://app.knovel.com/hotlink/toc/id:kpAPE00015/aircraft-propulsion-
2nd/aircraft-propul sion-2nd
[6] Dean W. R., Hurst J. M. (17 Apr 1959). “Note on the Motion of Fluid in a Curved
Pipe.” Cambridge University Press. [Online]. Available:
https://www.cambridge.org/core/services/aop-cambridge-
core/content/view/S0025579300 001947. [Accessed: 26 Sept 2018].
[7] Mohammed K. Ibrahima (corresponding author), A. F. Abohelwab and Galal B.
Salem. (2009). “Design, Fabrication, and Realization of a Supersonic Wind Tunnel for
Educational Purposes.” Manchester University Press. [Online]. Available at:
https://scholar.cu.edu.eg/sites/default/files/mkhalil/files/11_ijmee_vol_37_no_4_oc
t_2009 _m_k_ibrahim_et_al.pdf.
[8] Joseph H. Ruf , David M. McDaniels, Andrew M. Brown. (2004). “Nozzle Side Load
Testing and Analysis at Marshall Space Flight Center.” NASA Marshall Space Flight
Center. [Online]. Available at:
https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100017649.pdf.
The Ohio State University / College of Engineering / Department of Mechanical and Aerospace Engineering
PREVIOUS SET-UP
• No Settling Chamber after Regulator
• Exhausts to the air
• Curved Piping
• Uses cold gas: Compressed Air
• Non Uniform flow
ORGINAL PROPOSED DESIGN
QUASI 1-D THEORY
VALIDATION OF HYPOTHESIS
• The pressure threshold with regards to time was satisfied with
regards to time (0.43 psi, at 0.08 psi. )
• Threshold with regards to uniformity in the radial direction
was just outside the desired margins ( 1.34 psi, at 2.56 psi)
• Need to investigate impact of leaks ⇒ Could be good or bad
• Overall the hypothesis was not strictly met, but objectives and
success criteria were