Open Access

ARTICLE

A Mixed Radiative-Convective Technique for the Calibration of Heat Flux Sensors in Hypersonic Flow

Antonio Esposito¹, Marcello Lappa^2,*, Rocco Pagliara³, Gennaro Spada¹

1 Department of Industrial Engineering, University of Naples, Naples, 80125, Italy
2 Department of Mechanical and Aerospace Engineering, University of Strathclyde, Glasgow, G1 1XJ, UK
3 Cheminox srl, San Vito dei Normanni (BR), 72019, Italy

* Corresponding Author: Marcello Lappa. Email:

Fluid Dynamics & Materials Processing 2022, 18(2), 189-203. https://doi.org/10.32604/fdmp.2022.019605

Received 01 October 2021; Accepted 29 October 2021; Issue published 16 December 2021

Abstract

The ability to measure the very high heat fluxes that typically occur during the hypersonic re-entry phase of space vehicles is generally considered a subject of great importance in the aerospace field. Most of the sensors used for these measurements need to be checked periodically and re-calibrated accordingly. Another bottleneck relates to the need to procure thermal sources that are able to generate reliable reference heat fluxes in the range between 100 and 1000 kW/m² (as order of magnitude). In the present study, a method is presented by which, starting from a calibration system with a capacity of approximately 500 kW/m² only, heat fluxes in the range of interest for hypersonic applications are generated. The related procedure takes advantage of established standards for the characterization of a radiative heat flux. It also builds on the hybrid radiative-convective nature of typical hypersonic heat fluxes and the yet poorly explored possibility to use convective sources of heat to produce high-intensity fluxes. The reliability of such a strategy has been tested using a high enthalpy supersonic flow facility relying on an electric arc-heater and pure Nitrogen as work gas. Stagnation-point heat fluxes have been successfully measured (with reasonable accuracy) in the range between 600 and 1500 kW/m² for values of the centerline enthalpy spanning the interval from to 6 to 24 MJ/kg.

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Keywords

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