Comparison of Calorimetric Sensors - NASA Ames and IRS

Abstract

A space act agreement between NASA Ames Research Center and the Institute of SpaceSystems at the University of Stuttgart was put in place in October 2011. The focus of this collaboration is the comparison and refinement of measurement techniques for plasma characterization. Within this paper, first test results from this collaboration will be presented, based on tests completed at NASA Ames arc jet facilities. A water-cooled energy balance calorimeter and a null-point calorimeter from the Institute of Space Systems were compared to a slug calorimeter and null-point calorimeter from NASA Ames. The results are expected to serve the plasma and entry community by providing comparative data between the two facilities and the three types of sensors.

Comparison of Heat Flux Gages for High Enthalpy Flows - NASA Ames and IRS

“…It is this condition that was intended to be comparable to the condition Ames-IRS1 of the campaign at ARC. 1 The condition was newly established. The reference data set for the condition are total pressure and heat flux.…”

“…The probe head was damaged likely due to heating during the campaign at ARC. 1 The whole inner structure was therefore replaced and new resistance thermometers (pt100) were installed for this campaign. The working principle of this calorimetric is the following: A well insulated surface of the probe in the stagnation region is cooled by a separate water cooling circuit.…”

“…In a first step, tests were conducted with null-point sensors and calorimeters from both institutions tested at ARC and IRS facilities. 1 This approach is used to compare sensors and facilities, laying the groundwork for future activities and joint tests. This paper presents the second part -the testing at IRS with ARC and IRS sensors.…”

Experimental Characterization of Ablation Species in an Air Plasma Ablating Boundary Layer

“…Understanding the physics of the interactions between plasmas and ablating materials is helpful for more accurate design and performance predictions, and can lead to a decrease in shield mass and a safer thermal protection system. Previous studies have investigated the coupling between atmospheric plasma flows and ablating materials [1][2][3][4][5][6][7][8][9][10][11]; the current work seeks to extend these studies to provide new data at higher heat fluxes and surface temperatures. The current study employs emission spectroscopy and visual imaging diagnostics to investigate the boundary layer of an ablating material in the high enthalpy flow of an inductively coupled plasma torch.…”

Review of Heat Flux Measurements for High Enthalpy Flows

“…34,58 Here, the condition was defined by measuring heat flux and total pressure with one of the sensors and comparing all other sensors against this first data set. The advantage of this procedure is that a shear facility effect is excluded with respect to the heat flux data acquisition.…”