Development of a Thermal Probe Method for Heat Flux and Ion Temperature Measurement in the Divertor Simulator MAP-II

Abstract The present investigations provide a pathway for implementation of soft computing based Adaptive Neuro-Fuzzy Inference System (ANFIS) technique for prediction of surface heat flux from short duration temperature measurement in shock tubes or shock tunnels. Computational modeling of a co-axial thermal probe is carried out to get the necessary temperature-time histories for different temporal variations of applied heat loads. Different possible inputs are assessed while defining the most suitable ANFIS structure for the recovery of step or ramp heat loads. This proposition is then tested for recovery of heat flux in a given range or of given time history. In each case, the uncertainty band is found to be in the acceptable range. The final assessment of this novel methodology is performed for recovery of heat flux signal from temperature measurement in a shock tube-based experiment. An in-house fabricated fast response coaxial thermal probe (CTP), prepared from chromel (3.25 mm diameter and 10 mm length) and constantan (0.91mm diameter and 15 mm length) is employed for these experiments. The surface heat flux recovered from the experimental signal using ANFIS is seen to have excellent agreement with the conventional analytical method in terms of both trend and magnitude, within an uncertainty band of ± 2%. Therefore present investigations advocate the use of soft computing technique for heat flux recovery in a short duration temperature measurement due to its accuracy of prediction, lesser complexities in mathematical modeling, and being less computationally intensive.

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ERRATUM: Ion Temperature Measurement of a Streaming He Plasma by a Double Probe Method

Applied Physics Letters ◽

10.1063/1.1754546 ◽

1966 ◽

Vol 8 (7) ◽

pp. 185-185 ◽

Cited By ~ 1

Author(s):

Nobuki Kawashima

Keyword(s):

Temperature Measurement ◽

Probe Method ◽

Ion Temperature ◽

Double Probe

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ION TEMPERATURE MEASUREMENT OF A STREAMING He PLASMA BY A DOUBLE PROBE METHOD

Applied Physics Letters ◽

10.1063/1.1754281 ◽

1965 ◽

Vol 7 (12) ◽

pp. 324-325 ◽

Cited By ~ 2

Author(s):

Nobuki Kawashima

Keyword(s):

Temperature Measurement ◽

Probe Method ◽

Ion Temperature ◽

Double Probe

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Sputter Deposited Metal Layers Embedded in Composites—From Fundamentals to Applications

Coatings ◽

10.3390/coatings11020190 ◽

2021 ◽

Vol 11 (2) ◽

pp. 190

Author(s):

Florian Cougnon ◽

Mathias Kersemans ◽

Wim Van Paepegem ◽

Diederik Depla

Keyword(s):

Thin Films ◽

Heat Flux ◽

Sputter Deposition ◽

Image Correlation ◽

Fiber Reinforced Polymers ◽

Thermal Probe ◽

Reinforced Polymers ◽

Magnetron Sputter Deposition ◽

Sputter Deposited ◽

Metal Layers

Due to the low heat flux towards the substrate, magnetron sputter deposition offers the possibility to deposit thin films on heat sensitive materials such as fiber-reinforced polymers, also known as composite materials. Passive thermal probe measurements during the sputter deposition of metal layers show indeed that the temperature increase remains well below 25 °C for film thicknesses up to 600 nm. The latter thickness threshold is based on the influence of embedded metal films on the adhesion of the composite plies. Films thicker than this threshold deteriorate the mechanical integrity of the composite. The introduction of the uncured composite in the vacuum chamber strongly affects the base pressure by outgassing of impurities from the composite. The impurities affect the film properties as illustrated by their impact on the Seebeck coefficient of sputter deposited thermocouples. The restrictions to embed thin films in composites, as illustrated by both the heat flux measurements, and the study on the influence of impurities, are however not insurmountable. The possibility to use embedded thin films will be briefly demonstrated in different applications such as digital volume image correlation, thermocouples, and de-icing.

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Optimum pulse length of a high-power SMM laser for Tokamak ion temperature measurement

Plasma Physics ◽

10.1088/0032-1028/24/10/009 ◽

1982 ◽

Vol 24 (10) ◽

pp. 1325-1329 ◽

Cited By ~ 3

Author(s):

T Okada ◽

K Kato ◽

R Noudomi ◽

M Muraoka ◽

M Akazaki

Keyword(s):

Temperature Measurement ◽

High Power ◽

Pulse Length ◽

Ion Temperature

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Uncertainty Quantification of Thermocouple Air Temperature Measurement in Highly Radiative Environment: Application to Turbofan Engine Compartment

Volume 5A: Heat Transfer ◽

10.1115/gt2016-57938 ◽

2016 ◽

Cited By ~ 1

Author(s):

Y. Sommerer ◽

V. Drouin ◽

X. Nicolas ◽

B. Trouette

Keyword(s):

Heat Flux ◽

Temperature Measurement ◽

Air Temperature ◽

Data Bank ◽

Heat Shield ◽

Engine Compartment ◽

Heat Shields ◽

Air Speed ◽

Thermocouple Temperature ◽

The Impact

This paper focuses on thermocouple air temperature measurement uncertainty due to the radiative fluxes present in the engine compartment where engine case skin temperature can exceed 900 K. To really measure air temperature, the convective heat flux in the thermocouple bead must be predominant. This is why heat shields are used in order to reduce the radiative heat flux on the bead. However, in engine compartment, the heat shield orientation must be optimized since numerous hot walls surround the thermocouple. In order to evaluate the impact of badly oriented heat shields and to provide a data bank for numerical simulation validations, a heated wind tunnel has been used. It has been shown that the uncertainty on the thermocouple temperature can reach dozens of degrees depending on the air speed and the heat shield orientation. Furthermore a specific 3D thermocouple model has been build and validated by comparison with the lab measurements. Then this thermocouple 3D model has been integrated in the whole engine compartment aero-thermal model in order to quantify the uncertainty of the thermocouple air temperature measurement in the real engine environment.

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