The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions
In a two-phase heat exchanger, the thermal boundary condition at the boiling wall plays an import role. To investigate the characteristics of its flow and heat transfer, it is required to solve a three-domain conjugation heat transfer problem which takes into account of boiling, conduction, and air...
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sg-ntu-dr.10356-836002021-01-10T10:52:14Z The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions Qiu, Lu Dubey, Swapnil Choo, Fook Hoong Duan, Fei School of Mechanical and Aerospace Engineering Energy Research Institute @ NTU (ERI@N) Conjugation heat transfer Jet impingement boiling In a two-phase heat exchanger, the thermal boundary condition at the boiling wall plays an import role. To investigate the characteristics of its flow and heat transfer, it is required to solve a three-domain conjugation heat transfer problem which takes into account of boiling, conduction, and air convection. In the current design, the saturated water flows into a cylindrical chamber with a tube array, whereas the hot air travels outside of chamber and boils the water inside. The effects of the water inlet velocity and hot air inlet mass flow rate are measured in the experiments. A simulation tool with Graphical User Interface code is developed for predicting the three-domain conjugation heat transfer. The boiling heat transfer in the complex case is showed to be well explained in the approach of combining the Rensselaer Polytechnic Institute (RPI) boiling model. The experiments indicate that the wall temperature on the solid-air interface and the transferred energy are independent of water inlet velocity but significantly depend on the air inlet mass flow rate. The wall temperatures in the centre core area (tube array region) are relatively uniform, whereas a huge temperature gradient is measured in the peripheral area. The maximum temperature difference in the core region is only around 17.7% or 24.6% of the core-to-peripheral temperature difference in the cases with the high or low air inlet velocity. The experimental observations have been reproduced in the simulation. The heat transfers on the hot air side and the water boiling side significantly influence each other. Prominent variations of wall temperature and heat flux result in a co-existence of single-phase water convection and the water boiling flow. It demonstrates that the conjugation has to be considered with applying an ad hoc thermal boundary conditions in the cases. NRF (Natl Research Foundation, S’pore) Accepted version 2017-06-22T04:51:14Z 2019-12-06T15:26:29Z 2017-06-22T04:51:14Z 2019-12-06T15:26:29Z 2016 Journal Article Qiu, L., Dubey, S., Choo, F. H., & Duan, F. (2016). The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions. Applied Thermal Engineering, 108, 456-465. 1359-4311 https://hdl.handle.net/10356/83600 http://hdl.handle.net/10220/42738 10.1016/j.applthermaleng.2016.07.134 en Applied Thermal Engineering © 2016 Elsevier Ltd. This is the author created version of a work that has been peer reviewed and accepted for publication by Applied Thermal Engineering, Elsevier Ltd. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1016/j.applthermaleng.2016.07.134]. 39 p. application/pdf |
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Conjugation heat transfer Jet impingement boiling Qiu, Lu Dubey, Swapnil Choo, Fook Hoong Duan, Fei The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
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In a two-phase heat exchanger, the thermal boundary condition at the boiling wall plays an import role. To investigate the characteristics of its flow and heat transfer, it is required to solve a three-domain conjugation heat transfer problem which takes into account of boiling, conduction, and air convection. In the current design, the saturated water flows into a cylindrical chamber with a tube array, whereas the hot air travels outside of chamber and boils the water inside. The effects of the water inlet velocity and hot air inlet mass flow rate are measured in the experiments. A simulation tool with Graphical User Interface code is developed for predicting the three-domain conjugation heat transfer. The boiling heat transfer in the complex case is showed to be well explained in the approach of combining the Rensselaer Polytechnic Institute (RPI) boiling model. The experiments indicate that the wall temperature on the solid-air interface and the transferred energy are independent of water inlet velocity but significantly depend on the air inlet mass flow rate. The wall temperatures in the centre core area (tube array region) are relatively uniform, whereas a huge temperature gradient is measured in the peripheral area. The maximum temperature difference in the core region is only around 17.7% or 24.6% of the core-to-peripheral temperature difference in the cases with the high or low air inlet velocity. The experimental observations have been reproduced in the simulation. The heat transfers on the hot air side and the water boiling side significantly influence each other. Prominent variations of wall temperature and heat flux result in a co-existence of single-phase water convection and the water boiling flow. It demonstrates that the conjugation has to be considered with applying an ad hoc thermal boundary conditions in the cases. |
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School of Mechanical and Aerospace Engineering |
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School of Mechanical and Aerospace Engineering Qiu, Lu Dubey, Swapnil Choo, Fook Hoong Duan, Fei |
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Article |
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Qiu, Lu Dubey, Swapnil Choo, Fook Hoong Duan, Fei |
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Qiu, Lu |
title |
The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
title_short |
The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
title_full |
The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
title_fullStr |
The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
title_full_unstemmed |
The jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
title_sort |
jet impingement boiling heat transfer with ad hoc wall thermal boundary conditions |
publishDate |
2017 |
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https://hdl.handle.net/10356/83600 http://hdl.handle.net/10220/42738 |
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1690658486898130944 |