A Hybrid Method for Measuring Heat Flux

The development and evaluation of a novel hybrid method for obtaining heat flux measurements is presented. By combining the spatial and temporal temperature measurements of a heat flux sensor, the time response, accuracy, and versatility of the sensor is improved. Sensors utilizing the hybrid method are able to make heat flux measurements on both high and low conductivity materials. It is shown that changing the thermal conductivity of the backing material four orders of magnitude causes only an 11% change in sensor response. The hybrid method also increases the time response of heat flux sensors. The temporal response is shown to increase by up to a factor of 28 compared with a standard spatial sensor. The hybrid method is tested both numerically and experimentally on both high and low conductivity materials and demonstrates significant improvement compared with operating the sensor as a spatial or temporal sensor alone.

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Response of Finite-Thickness Gardon Heat-Flux Sensors

Journal of Heat Transfer ◽

10.1115/1.3449912 ◽

1972 ◽

Vol 94 (2) ◽

pp. 244-245 ◽

Cited By ~ 9

Author(s):

Robert H. Kirchhoff

Keyword(s):

Heat Flux ◽

Aspect Ratio ◽

Integral Transform ◽

Finite Thickness ◽

Time Response ◽

Heat Flux Sensor ◽

Heat Flux Sensors ◽

Temperature Time ◽

Integral Transform Technique ◽

Flux Sensor

The temperature–time response of a Gardon heat-flux sensor of finite thickness has been calculated by the integral-transform technique. Through the introduction of the aspect ratio, results are presented which characterize the response of a finite-thickness probe compared to a probe of zero thickness.

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Novel portable device to analyze the moisture permeability of car seat

Industria Textila ◽

10.35530/it.069.03.1455 ◽

2018 ◽

Vol 69 (03) ◽

pp. 183-189

Author(s):

MAZARI FUNDA BUYUK ◽

MAZARI ADNAN ◽

HAVELKA ANTONIN ◽

GLOMBIKOVA VIERA

Keyword(s):

Heat Flux ◽

Pid Controller ◽

Portable Device ◽

Heat Flux Sensor ◽

The Real ◽

Car Seats ◽

Car Seat ◽

Testing Method ◽

Heat Flux Sensors ◽

Flux Sensor

The comfort performance of car seat is important factor while producing car seats, each layer of the car seat is tested separately on classical testing machines, which lacks the real car seat performance when all layers are sandwiched. The complication of car seat design and the testing method bring a great demand of portable device which can measure the comfort performance of the real car seat. In this research a novel portable device is designed which work with special heat flux sensor and the device is connected to computer by USB port and values of heat flux temperature of the water and temperature of the surface is provided by the software. Heat flux sensors measure the heat transfer through a surface, and are expressed in kw/m2. The software controls the heating plate adjustment using PID controller. The device is tested with real car seat and shows repeatable and reproducible results.

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Flexible Heat Flux Sensor for Firefighters Garment Integration

International Journal of E-Health and Medical Communications ◽

10.4018/jehmc.2013010104 ◽

2013 ◽

Vol 4 (1) ◽

pp. 36-45

Author(s):

Christelle Navone ◽

Mathieu Soulier ◽

Isabella Chartier ◽

Julia Simon ◽

Aurelien Oliveira ◽

...

Keyword(s):

Heat Flux ◽

Thermoelectric Materials ◽

Low Cost ◽

High Sensitivity ◽

Heat Flux Sensor ◽

Proof Of Concept ◽

Fire Fighters ◽

European Project ◽

Heat Flux Sensors ◽

Flux Sensor

The interest in using optimal equipment to face unknown hazards is growing, as it ultimately save lives. This holds especially true for fire-fighters which are confronted with other hazards during the course of operations. Improvement of their security by an integrated sensory clothing system was the main objective of the European project ProeTEX. In this context, the integration of commercial heat flux sensors into fire-fighters garment has proved the interest of such measurements. However, low flexibility and high cost remain major disadvantages of these sensors. The objective of this work is to develop an innovative heat flux sensor based on a low cost technology. Heat flux sensors have been realized using printable thermoelectric materials and present high sensitivity (146 mV/ (W/cm2)). Their flexibility is compatible with integration in clothes and three specific integrations are proposed and compared. Proof of concept of flexible heat flux sensor is also presented in this paper.

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Time-Resolved Heat Transfer Measurements on the Tip Wall of a Ribbed Channel Using a Novel Heat Flux Sensor: Part I — Sensor and Benchmarks

Volume 3: Heat Transfer, Parts A and B ◽

10.1115/gt2006-91129 ◽

2006 ◽

Cited By ~ 7

Author(s):

Tim Roediger ◽

Helmut Knauss ◽

Uwe Gaisbauer ◽

Ewald Kraemer ◽

Sean Jenkins ◽

...

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Turbine Blades ◽

Temperature Fields ◽

Heat Flux Sensor ◽

Internal Cooling ◽

Time Resolved ◽

Flux Measurements ◽

Working Principle ◽

Flux Sensor

A novel heat flux sensor was tested which allows for time-resolved heat flux measurements in internal ribbed channels related to the study of passages in gas turbine blades. The working principle of the Atomic Layer Thermopile (ALTP) sensor is based on a thermoelectric field created by a temperature gradient over an YBCO crystal (the transverse Seebeck effect). The sensors very fast frequency response allows for highly time-resolved heat flux measurements up to the 1 MHz range. This paper explains the design and working principle of the sensor, as well as the benchmarking of the sensor for several flow conditions. For internal cooling passages, this novel sensor allows for highly accurate, time-resolved measurements of heat transfer coefficients, leading to a greater understanding of the influence of fluctuations in temperature fields.

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Temperature Coefficient of Thin Film Resistance Temperature Detectors for Improved Heat Flux Sensors

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.378.302 ◽

2013 ◽

Vol 378 ◽

pp. 302-307 ◽

Cited By ~ 3

Author(s):

B. Azerou ◽

B. Garnier ◽

A. Lahmar

Keyword(s):

Thin Film ◽

Heat Flux ◽

Temperature Coefficient ◽

Flux Measurement ◽

External Boundary ◽

Heat Flux Sensor ◽

Film Resistance ◽

Heat Flux Sensors ◽

The One ◽

Flux Sensor

The measurement of thermal properties or internal or external boundary conditions requires temperature and heat flux data. Both information can be provided by heat flux sensors. The one consisting in measuring temperature at various locations within the wall and using inverse method to estimate wall temperature and heat flux is among those providing the lowest measurement bias for transient heat flux measurement. However, this very accurate sensor requires time consuming technical work for microthermocouples implementation and due to the welding, one cannot locate precisely the temperature measurement. The idea developed in this work is to replace the wire microthermocouples by thin film resistance temperature detectors deposited on polymer substrate in order to ease the fabrication and to increase the accuracy of heat flux sensor. As the deposited sensors are RTDs, a preliminary study is performed showing the effect of the metal as well as the processing conditions on the electrical resistivity and temperature coefficient of copper and aluminum thin film

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Performance and Modeling of Heat Flux Sensors in Different Environments

10.1115/imece1999-1105 ◽

1999 ◽

Author(s):

D. G. Holmberg ◽

C. A. Womeldorf

Keyword(s):

Heat Flux ◽

Flux Measurement ◽

Heat Flux Sensor ◽

Environment Modeling ◽

Sensor Performance ◽

Heat Flux Sensors ◽

Substrate Properties ◽

Accuracy Of Measurement ◽

Flux Calibration ◽

Flux Sensor

Abstract Heat flux measurement is not simple; care is required in selecting a suitable sensor for a given application. Surface substrate properties and the convective and radiative environment determine the choice of sensors. Mounting of the sensor, especially in calibration versus application, influences accuracy of measurement. The purpose of the present study is to increase awareness of potential errors in heat flux sensor use. This paper compares sensor performance in general by examining results of testing three commercially available sensors and by numerical modeling of these sensors. Comparisons of sensor calibrations in the NIST convective heat flux calibration facility are made with manufacturer calibrations and give evidence of potential pitfalls when using a sensor in a different environment than the calibration environment. Modeling results help explain observed data, demonstrating specific sensor parameters that can lead to significantly different calibrations in different environments.

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Time-Resolved Heat Transfer Measurements on the Tip Wall of a Ribbed Channel Using a Novel Heat Flux Sensor—Part I: Sensor and Benchmarks

Journal of Turbomachinery ◽

10.1115/1.2751141 ◽

2008 ◽

Vol 130 (1) ◽

Cited By ~ 16

Author(s):

Tim Roediger ◽

Helmut Knauss ◽

Uwe Gaisbauer ◽

Ewald Kraemer ◽

Sean Jenkins ◽

...

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Turbine Blades ◽

Temperature Fields ◽

Heat Flux Sensor ◽

Internal Cooling ◽

Time Resolved ◽

Flux Measurements ◽

Working Principle ◽

Flux Sensor

A novel heat flux sensor was tested that allows for time-resolved heat flux measurements in internal ribbed channels related to the study of passages in gas turbine blades. The working principle of the atomic layer thermopile (ALTP) sensor is based on a thermoelectric field created by a temperature gradient over an yttrium-barium-copper-oxide (YBCO) crystal (the transverse Seebeck effect). The sensors very fast frequency response allows for highly time-resolved heat flux measurements up to the 1MHz range. This paper explains the design and working principle of the sensor, as well as the benchmarking of the sensor for several flow conditions. For internal cooling passages, this novel sensor allows for highly accurate, time-resolved measurements of heat transfer coefficients, leading to a greater understanding of the influence of fluctuations in temperature fields.

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