衝擊熱傳研究及有限時間熱力循環

Analyses on Impinging Heat Transfer and Finite-Time Thermodynamics

邱建穎(Jian-Ying Qiu)

指導教授 ： 侯順雄

崑山科技大學/工程學院/機械工程研究所/碩士(2003年)

https://doi.org/10.6828/KSU.2003.00019

摘要

本論文分為兩大部份：
(一)衝擊熱傳研究：探討的方向有二(1)正向衝擊熱傳(2)側(橫)向衝擊熱傳。在正向噴流衝擊熱傳中，將以矩形雙噴管之二維數值作模擬分析，分為矩形單噴管及矩形雙噴管兩項。矩形單噴管的研究中將探討：邊界條件(自由噴流衝擊及半侷限邊界噴流衝擊)及出口條件(展開流及均勻流)對流場的影響；(2)側(橫)向噴流衝擊熱傳，將以三維數值模擬作分析，並以空氣為散熱介質，探討雷諾數、鰭片形狀傾斜和上平板傾斜設計對流場散熱效益的影響
(二)有限時間熱力分析：主要是應用有限時間熱力學，從穩態系統的觀點，以不同目標函數來探討不同熱機之性能最佳化。研究的題目有三：(1)等溫熱源、內可逆迪賽爾熱機之生態學準則函數最佳化(2) 等溫熱源、內可逆奧圖熱機之生態學準則函數最佳化(3) 等溫熱源、內可逆阿京生熱機之生態學準則函數最佳化。

關鍵字

散熱片 ； 有限時間 ； 熱機

並列摘要

First, the flow and heat transfer characteristics of an impinging laminar slot-jet, twin impinging laminar slot-jets, and heat sinks with sloped plate fins as well as with an inclined confinement surface are investigated by using the Star-CD software.
Parameters examined for a single jet include the width of the jet, Reynolds number, the separation distance between the slot-jet exit plane and the impingement surface, free-jet impingement or semiconfined-jet impingement, uniform inlet flow or fully-developed inlet flow.
An additional parameter, the separation distance between the twin jets is examined for the analysis on the dual jets. In addition, the effects of the titling of the crests of the plate fins relative to the approaching flow and the inclined confinement surface are found to be indeed the two important heat transfer augmentation features.
Secondly, a steady-flow approach in finite-time thermodynamics is employed to investigate the ecological-criterion function optimizations of the endoreversible Diesel, Otto, and Atkinson heat engines with isothermal heat sources. The results show that adopting the ecological-criterion function as the objective function, a heat engine may achieve the balance among the power output, thermal efficiency and entropy generation rate.

並列關鍵字

finite-time ； heat engine ； heat sinks

參考文獻

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