Date of Award


Degree Name

MS in Mechanical Engineering


Mechanical Engineering


College of Engineering


Kim Shollenberger, Nandeesh Hiremath

Advisor Department

Aerospace Engineering

Advisor College

College of Engineering


This paper determines the feasibility of adding a heater to an existing blowdown supersonic wind tunnel to unlock new high-enthalpy test applications, considering cost and power requirements at a variety of different states. This process includes both modeling the current range of test section properties in Cal Poly's blowdown wind tunnel and determining the new range of properties that a heat exchanger could induce. These results are verified with a computational fluid dynamics study. Additionally, sublimation and ablation properties of materials are explored to create appropriate models to study atmospheric re-entry once the heat exchanger is implemented.

It is found that adding a heater to the supersonic wind tunnel would significantly increase the test section temperature. Additionally, enough heat could be added without damaging the facility to surpass the vapor pressure of camphor and naphthalene at test section conditions, allowing for the tunnel to be used for sublimation and ablation applications. Using the tunnel with the variable Mach nozzle currently installed would induce minimum heater power requirements of 75kW for a Mach 4 configuration and 200kW for the testing Mach 3.13 condition to reach this vapor pressure. However, this power requirement can be significantly reduced by installing a new nozzle that would induce flow at a Mach number of 6-8. Liquefaction is found to be avoided at every test and Mach condition, even without any heat added, while condensation cannot be avoided at any configuration, regardless of nozzle used or heat added. Therefore, we recommend that a dryer be installed to help remedy these issues.

Award received:

1st Place Master's Category, AIAA 2022 Region VI Student Conference