本文利用STAR-CCM+軟體，對超級橢圓截面結構內管的套管式換熱器進行模擬，主要探討一外管為冷流之圓形絕熱管，內管為熱流之超級橢圓管的套管逆流換熱器，在不同截面結構之下的傳熱效能。
超級橢圓截面除了長短軸的長度與比例外，還多了次方數N可以進行調整，本文所探討的結構將透過調整這兩個參數在紊流流場下，進行套管換熱器的熱傳模擬，藉由在同樣溫度差條件下模擬光滑內管的熱傳，並且採用場協同角理論、火積耗散理論與綜合評價指標PEC對傳熱強化的效果進行分析，比較結果並建立模擬數據。為了證明效能的提升，本文使用了平均場協同角、基於積耗散理論所建立的當量熱阻、紐塞數、摩擦因子、PEC指標與雷諾數等參數，來對換熱器進行評估。
透過模擬之結果發現，提升其內管截面之次方數N值，對應相同截面積之內管，在長短軸比為12：12可以得到熱傳效果的提升，然而因為選擇的評估方法所考量的因素有所不同，有可能會得到不同的趨勢；在長短軸比為16：9的等截面積內管雖然相對於圓管效益皆有提升，但是其會隨N值上升而熱傳效益遞減。而提高其流速雖然會如預期得到熱傳提升的效果，但是提升的效益，也會因為選擇的方法所考慮的因素而有所減低。

This paper studied the convective heat transfer efficiency of double pipe heat exchangers with superellipse inner section. Using "STAR CCM+" which is capable of handling wide range of common flow simulation with finite element method for numerical analysis, this paper focus on double pipe heat exchangers containing various superellipse inner cross sections and adiabatic outer tube wall for counter flow configurations. Working fluid in the simulation were hot and cold water which flowed in the inner tube and outer tube of the heat exchangers.
The parameters to decide the superellipse cross-section is not only the semi-major axis and the simi-minor axis for their length and ratio, but the degree N of the curve. The structure of the inner double pipe cross section in this paper is designed with both the ratio of semi axis ane the degree of curves. In order to achieve the lifting of heat transfer, we refer to three methods -field synergy principle, entransy dissipation Theory and performance evaluation criterion (PEC) and compare the assessment from them.
To prove the adventage of different shaped inner section, we observe heat exchanger by mean field synergy angle, equivalent thermal resistance based on entransy dissipation theorem, Nusselt number, Darcy friction factor ,PEC and Renolds Number. PEC is a term applied to judge whether this kind of heat exchanger is efficient or not. When we lift the heat transfer, we need to take pump power consumption into consideration. If the pump power consumption rate of increase is greater than heat transfer's rate of increase, this heat exchanger is not efficient.
With same mean fluid velocity input and same inner cross section area, in other words, with same flow rate, this paper concluded the improvement of efficiency in both the increase of degree N case and increase of semi axis ratio case. And the rate of efficiency increase may differ from theorem used for assessment.

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