以紅外線測溫與質點影像測速技術研究平行與交錯翼型擾流器於雙通道之紊性熱傳增益

IRT and PIV Investigations of Turbulent Heat Transfer Enhancement in a Two Pass Channel with Inline and Staggered Wing-Shaped Turbulators

李偉瑄(Wei-Shiuan Lee)

指導教授 ： 劉通敏 ； 王春生

國立清華大學/工學院/動力機械工程學系/碩士(2022年)

摘要

近年來，隨著全球能源需求不斷的增加以及化石能源儲備的日漸枯竭，如何更有效率地運用有限化石能源是全球面臨的共同課題。目前使用的燃料大多都通過熱能轉換供社會或工業使用，因此提升熱交換器的熱傳性能是提升能源利用效率的重要方式之一。本研究在前人最佳設計之具翼型擾流器之蛇形方管熱交換器基礎上，進一步優化擾流器擺放方式以增益其熱傳，並使用紅外線熱像儀(Infrared Thermography，簡稱IRT)、壓力傳感器以及質點影像測速儀(Particle Image Velocimetry，簡稱PIV)量測方管中局部溫度分布、壓力損失以及流場結構，以便探討流場結構如何影響熱傳增益與壓力損失。
本研究使用之翼形擾流器皆為3D列印所印製，按照與管道壁面貼合方式可分為I (側壁貼合)、II (上下壁面貼合)、III (下壁面貼合)三種類型，擺放方式為平行(Inline)或交錯(Staggered)。IRT熱傳與壓損量測實驗於雷諾數(

關鍵字

翼型擾流器 ； 正方形雙通道 ； 熱流相關性 ； 紅外線熱像儀 ； 質點影像測速儀

並列摘要

In recent years, due to the growing demand for energy and depletion of fossil fuels, the efficient use of the limited fossil fuels becomes a challenge facing our planet. As most fuels for residential and industrial applications nowadays are utilized in the way of thermal energy, increasing the thermal performance of heat exchangers is one of the most important methods to improve the efficiency of energy use. This research aims to enhance the thermal performance of previous wing-shaped turbulators in a square serpentine channel with different turbulator arrangements. To explore the effects of turbulent flow structures on heat transfer and pressure loss, the Infrared Thermography (IRT), pressure sensors, and Particle Image Velocimetry (PIV) are applied to measure the local temperature distributions, pressure loss and flow fields, respectively.
In this study, according to the wall attachment methods the adopted turbulators fabricated by the 3D printing technology can be categorized into three types: I (attached to the sidewalls), II (attached to the top and bottom walls) and III (attached to the bottom wall). The arrangement of the turbulators inside the channel is either inline or staggered. In the IRT and pressure loss experiments, the Reynolds Number (

並列關鍵字

Wing-ShapedTurbulators ； Two-PassSquareChannel ； ThemalFluidRelationships ； IRT ； PIV

參考文獻

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