A Local Heat Flux Measurement Technique for Inclined Heat Exchanger Tubes

2006 ◽  
Vol 19 (1) ◽  
pp. 1-14 ◽  
Author(s):  
T. Wu ◽  
K. Vierow
Keyword(s):  
Heat Flux ◽  
Heat Exchanger ◽  
Measurement Technique ◽  
Flux Measurement ◽  
Local Heat ◽  
Heat Flux Measurement ◽  
Local Heat Flux

Local Heat Flux Measurement in a Permanent Magnet Motor at No Load

2013 ◽  
Vol 60 (11) ◽  
pp. 4852-4860 ◽  
Author(s):  
Hanne K. Jussila ◽  
Andrey V. Mityakov ◽  
Sergey Z. Sapozhnikov ◽  
Vladimir Y. Mityakov ◽  
Juha Pyrhonen
Keyword(s):  
Heat Flux ◽  
Permanent Magnet ◽  
Flux Measurement ◽  
Local Heat ◽  
Permanent Magnet Motor ◽  
Heat Flux Measurement ◽  
Local Heat Flux

scholarly journals New technique of the local heat flux measurement in combustion chambers of steam boilers

2011 ◽  
Vol 32 (3) ◽  
pp. 103-116 ◽  
Author(s):  
Jan Taler ◽  
Dawid Taler ◽  
Tomasz Sobota ◽  
Piotr Dzierwa
Keyword(s):  
Heat Flux ◽  
Flux Measurement ◽  
Local Heat ◽  
New Technique ◽  
Combustion Chambers ◽  
Heat Flux Measurement ◽  
Water Wall ◽  
Steam Boilers ◽  
Local Heat Flux ◽  
Heat Flux Meter

New technique of the local heat flux measurement in combustion chambers of steam boilers A new method for measurement of local heat flux to water-walls of steam boilers was developed. A flux meter tube was made from an eccentric tube of short length to which two longitudinal fins were attached. These two fins prevent the boiler setting from heating by a thermal radiation from the combustion chamber. The fins are not welded to the adjacent water-wall tubes, so that the temperature distribution in the heat flux meter is not influenced by neighbouring water-wall tubes. The thickness of the heat flux tube wall is larger on the fireside to obtain a greater distance between the thermocouples located inside the wall which increases the accuracy of heat flux determination. Based on the temperature measurements at selected points inside the heat flux meter, the heat flux absorbed by the water-wall, heat transfer coefficient on the inner tube surface and temperature of the water-steam mixture was determined.

Design and Calibration of a Local Heat-Flux Measurement System for Unsteady Flows

1989 ◽  
Vol 111 (2) ◽  
pp. 552-557 ◽  
Author(s):  
D. S. Campbell ◽  
M. Gundappa ◽  
T. E. Diller
Keyword(s):  
Thin Film ◽  
Heat Transfer ◽  
Heat Flux ◽  
Measurement System ◽  
Radiant Energy ◽  
Unsteady Flows ◽  
Flux Measurement ◽  
Local Heat ◽  
Heat Flux Measurement ◽  
Local Heat Flux

A local heat–flux measurement system was built, calibrated, and tested for use in unsteady flows. The system was designed to maintain constant-wall-temperature boundary conditions. The measuring element is a thin-film heat flux gage made by sputter-coating gold onto a substrate. A constant-temperature anemometer is used to maintain the thin-film gage at a specified temperature under fluctuating conditions. A separate temperature control system maintains the surrounding boundary at the gage temperature. The system was calibrated for both steady and unsteady flows using a specially designed calibrator for local heat flux gages. The steady calibration was done with predominantly convective heat transfer. The unsteady calibration was achieved by adding oscillating radiant energy to the surface. Consequently, quantitative results can be obtained for both the mean and fluctuating components of the heat transfer. The frequency response was good to over 90 Hz. Sample results are presented of the unsteady heat transfer over a circular cylinder caused by natural vortex shedding at 70 to 80 Hz.

scholarly journals Gradient heat flux measurement during condensation at the surfaces of pipes

2019 ◽  
Vol 140 ◽  
pp. 06006
Author(s):  
Sergey Sapozhnikov ◽  
Vladimir Mityakov ◽  
Alexander Babich ◽  
Elza Zainullina
Keyword(s):  
Heat Flux ◽  
Local Heat Transfer ◽  
Flux Measurement ◽  
Local Heat ◽  
Steam Condensation ◽  
Transfer Coefficients ◽  
Pipe Length ◽  
Heat Transfer Coefficients ◽  
Heat Flux Measurement ◽  
New Information

Gradient heat flux measurement was used to study steam condensation at the inner and outer surfaces of pipes. Experimental setups were developed, manufactured and tested. The setups were able to incline the pipes for different angles relative to vertical and to rotate them around their main axes. Local heat transfer coefficients (HTC) along the pipe length and perimeter were determined. Formation and motion of condensate film were studied. The results are corresponding to classical ideas and give us some new information.

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