Heat Flux Measurement Using Swept Null Point Calorimetry

Powars, Charles; Kennedy, W.; Rindal, Roald A.

doi:10.2514/3.61773

Cited by 22 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Heat flux measurements for convective heat transfer are widely used in applications with harsh thermal environments including high enthalpy plasmas, high pressure arc heaters, high power pulsed lasers and structural thermal tests [21][22][23][24][25][26][27][28][29][30][31][32]. However, heat flux distribution measurements in high pressure, high temperature and hypersonic flows are still extremely difficult.…”

Section: Introductionmentioning

confidence: 99%

A method to measure heat flux in convection using Gardon gauge

Fu¹,

Zong²,

Zhang³

et al. 2016

Applied Thermal Engineering

View full text Add to dashboard Cite

Heat flux measurements are widely used in thermal environment analyses. The Gardon gauge is an excellent heat flux sensor with a wide measurement range and long lifespan in harsh environments. However, the Gardon gauge is usually calibrated for radiation heat transfer and is not good for convective heat transfer. This paper introduces a method to measure heat flux for convective heat transfer using the Gardon gauge by relating the measurement sensitivity for convection to that for radiation. The heat flux and convective heat-transfer coefficient can then be simultaneously determined by the standard thermo-electromotive voltage output of the Gardon gauge. The method was demonstrated for convective heat-transfer coefficient ranging from 200 to 3000 W/(m 2 K). The analysis illustrates that the measurement sensitivity for convection decreases with increasing convective heat-transfer coefficient. A correction is necessary especially for higher convective heat-transfer coefficient. The corrected convective heat-transfer coefficients and heat fluxes agree well with the actual values. The relative uncertainty in heat flux is within 0.64%. The method not only greatly improves the measurement accuracy of the Gardon gauge for convection applications, but also provides a reference for evaluating convective heat transfer coefficients in convection environments.

show abstract

Section: Introductionmentioning

confidence: 99%

A method to measure heat flux in convection using Gardon gauge

Fu¹,

Zong²,

Zhang³

et al. 2016

Applied Thermal Engineering

View full text Add to dashboard Cite

show abstract

“…A measurement of stagnation point surface heat flux to a blunt body probe is needed to estimate the mass-specific enthalpy of the flow [3]. Classical calorimeter style gauges or null-point calorimeters are typically used for this measurement [4][5][6]. Different types of heat flux gauge and different calibration methods used with the same gauge produce variations in surface heat flux measurements of up to 20 % [7], leading to significant uncertainty in the characterisation of the flow.…”

Section: Introductionmentioning

confidence: 99%

Stagnation Point Heat Flux Measurements in a Plasma Wind Tunnel Using a Diamond Heat Transfer Gauge

Geraets

McGilvray

2019

AIAA Scitech 2019 Forum

View full text Add to dashboard Cite

A Diamond Heat Transfer Gauge has been used to measure the stagnation point heat flux at three flow conditions in an arc heated plasma wind tunnel. The gauge was coated with a thin layer of copper to provide a known surface catalycity and reflectivity. The temperature dependent impulse response of the probe was determined from a finite element model of the probe, and from the result of a laser-based calibration experiment using the Non-Integer System Identification method. The two sets of impulse responses were used to calculate heat flux from a measured temperature rise in the wind tunnel. Differences between the impulse responses from the two methods, particularly at higher initial temperatures, led to differences in measured heat fluxes of up to 55 %. A measurement taken using a steady state calorimeter gauge did not conclusively agree with heat flux measurements calculated using impulse responses from either method.

show abstract

“…1 S. T. Hood, A. J. Dixon, and E. Weigold, J. Phys. We are indebted to Dr. Barat and his colleagues at Orsay and to Dr. G. Vassilev for providing us with the initial design.…”

mentioning

confidence: 99%