Development and testing of slug calorimeter and total pressure probes for a miniaturized arc-jet

Conference item

This work presents the development and experimental testing of small-scale slug calorimeter and total pressure probes, used to characterize a miniaturized thermal arc-jet facility at the University of Oxford. This instrumentation is used to determine the mass-specific stagnationpoint enthalpy of an argon plasma flow, allowing for characterization of the facility. The stagnation-point cold-wall heat flux rate is determined using a copper slug calorimeter, featuring a pair of ceramic insulators to minimize heat losses from the slug. Thermal simulations indicate heat losses of 3.97%, and a measurement accuracy of within 10%. Numerical analyses suggest achievable exposure times of 2s for the design condition. Experimental results for argon flowrates of 0.07 g/s and 0.15 g/s suggest heat losses ranging between 5% to 8%, with a maximum derived heat flux rate of 1.58 MW/m2. The stagnation pressure is determined with a total pressure probe, with measured values ranging between 1.98 kPa and 5.98 kPa for the flowrates tested. The experimentally derived stagnation enthalpy is calculated, with a maximum value of 4.95 MJ/kg achieved during testing.

Authors: Valeinis, O; Chang, EWK; Hermann, T

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Institute of Aeronautics and Astronautics
• Host title: AIAA SCITECH 2024 Forum
• Article number: 2886
• Publication date: 2024-01-04
• Acceptance date: 2024-01-04
• Event title: 2024 AIAA Science and Technology Forum and Exposition (AIAA SciTech Forum)
• Event location: Orlando, FL, USA
• Event website: https://aiaa.org/events/2024-aiaa-science-and-technology-forum-and-exposition-aiaa-scitech-forum/
• Event start date: 2024-01-08
• Event end date: 2024-01-12
• DOI: 10.2514/6.2024-2886
• Language: English
• Keywords: thin skin calorimeters; pressure probes; stagnation pressure; stagnation enthalpy; heat flux rate; principal stresses; thermocouples; compressive strength; specific heat capacity; heat transfer coefficients