An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition
Infrared transition location estimates can be fast and useful measurements in wind tunnel and flight tests. Because turbulent boundary layers have a much higher rate of convective heat transfer than laminar boundary layers, a difference in surface temperature can be observed between turbulent and la...
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ndltd-tamu.edu-oai-repository.tamu.edu-1969.1-ETD-TAMU-2012-08-114762013-01-10T17:38:14ZAn Examination of Configurations for Using Infrared to Measure Boundary Layer TransitionFreels, Justin Reedboundary layer transitioninfrared thermographyIR thermographywind tunnel testingaerodynamicsexperimental aerodynamicslaminar-to-turbulent transitionturbulent boundary layerInfrared transition location estimates can be fast and useful measurements in wind tunnel and flight tests. Because turbulent boundary layers have a much higher rate of convective heat transfer than laminar boundary layers, a difference in surface temperature can be observed between turbulent and laminar regions of an airfoil at a different temperature than the free stream air temperature. Various implementations of this technique are examined in a wind tunnel. These include using a heat lamp as an external source and circulating fluid inside of the airfoil. Furthermore, ABS plastic and aluminum airfoils are tested with and without coatings such as black paint and surface wraps. The results show that thermal conduction within the model and surface reflections are the driving issues in designing an IR system for detecting transition. Aluminum has a high thermal diffusivity so is a poor choice for this method. However, its performance can be improved using an insulating layer. Internal fluid circulation was far more successful than the heat lamp because it eliminates the reflected IR due to the heat lamp. However, using smooth surface wraps can mitigate reflection issues caused by the heat lamps by reducing the scatter within the reflection, producing an IR image with fewer contaminating reflections.White, Edward2012-10-19T15:29:56Z2012-10-22T18:03:39Z2012-10-19T15:29:56Z2012-10-22T18:03:39Z2012-082012-10-19August 2012thesistextapplication/pdfhttp://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11476en_US |
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en_US |
format |
Others
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boundary layer transition infrared thermography IR thermography wind tunnel testing aerodynamics experimental aerodynamics laminar-to-turbulent transition turbulent boundary layer |
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boundary layer transition infrared thermography IR thermography wind tunnel testing aerodynamics experimental aerodynamics laminar-to-turbulent transition turbulent boundary layer Freels, Justin Reed An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
description |
Infrared transition location estimates can be fast and useful measurements in wind tunnel and flight tests. Because turbulent boundary layers have a much higher rate of convective heat transfer than laminar boundary layers, a difference in surface temperature can be observed between turbulent and laminar regions of an airfoil at a different temperature than the free stream air temperature. Various implementations of this technique are examined in a wind tunnel. These include using a heat lamp as an external source and circulating fluid inside of the airfoil. Furthermore, ABS plastic and aluminum airfoils are tested with and without coatings such as black paint and surface wraps. The results show that thermal conduction within the model and surface reflections are the driving issues in designing an IR system for detecting transition. Aluminum has a high thermal diffusivity so is a poor choice for this method. However, its performance can be improved using an insulating layer. Internal fluid circulation was far more successful than the heat lamp because it eliminates the reflected IR due to the heat lamp. However, using smooth surface wraps can mitigate reflection issues caused by the heat lamps by reducing the scatter within the reflection, producing an IR image with fewer contaminating reflections. |
author2 |
White, Edward |
author_facet |
White, Edward Freels, Justin Reed |
author |
Freels, Justin Reed |
author_sort |
Freels, Justin Reed |
title |
An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
title_short |
An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
title_full |
An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
title_fullStr |
An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
title_full_unstemmed |
An Examination of Configurations for Using Infrared to Measure Boundary Layer Transition |
title_sort |
examination of configurations for using infrared to measure boundary layer transition |
publishDate |
2012 |
url |
http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11476 |
work_keys_str_mv |
AT freelsjustinreed anexaminationofconfigurationsforusinginfraredtomeasureboundarylayertransition AT freelsjustinreed examinationofconfigurationsforusinginfraredtomeasureboundarylayertransition |
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1716574691431284736 |