第五章 結論
為瞭解一冷卻渠道進行往復運動下，混合對流對ㄇ型渠道頂部的熱傳效率影 響，實際架設一組實驗設備來進來實驗，對ㄇ型渠道於靜止與往復運動狀態下，
探討不同振幅下的組合，並以數值模擬比對，提高實驗結果的可信度。最後將結 果歸納成以下結論:
1. ㄇ型渠道處於靜止狀態下時，由於受渠道幾何形狀及自然對流的影響，所以 前段加熱區熱傳效率最佳、中段加熱區次之、後段加熱區最差。
2. 當渠道進行振動時，壁面熱傳效率較靜止狀態時改善許多，在本實驗中最大 熱傳增益約為 48.6%。
3. 本實驗與文獻劉[30]中的實驗比較，本實驗熱傳效率較差，說明在ㄇ型渠道 中相同雷諾數，相同溫差，相同振動頻率，不同振幅下，振幅越高對於熱傳 效率有一定的助益。
參考文獻
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附錄一：實驗不準度分析
為提供有效的測試結果，並說明當次測試結果的信賴度，所以實驗不 準度的計算和分析是必要的，一般不準度的表示方式有絕對不準度與相對 不準度兩種，本文採用 Kline[27]之相對不準度來分析第四章實驗結果，
根據 Kline 之研究
當雷諾數 300，溫差(ΔT)=10℃時，取前段加熱區振動頻率
air in in lose lose
air air in air lose air air
air air
δQ Q Q Q Q Q Q Q Q
0.0005 0.0005
2.17 0.12
2 2 1 2
因此其不準度為
(ii) 巴沙木尺寸 62.00mm*12.00mm，游標尺最小刻度 0.05mm
(iii) 溫差最大範圍 45.775－44.875=0.9℃，DA2500E 之準確度為 0.1℃
(iii) 溫度差在 0.3℃之內皆視為等溫，故此項趨近於零。
(i) OB200 導熱膠熱傳導係數由說明書得知，其不準度趨近於零。
2 2 2
2 2 2 1/ 2
0.2604 0.0749 0.0001
0.42% 6.47% 2.08%
0.1324 0.1324 0.1324
0.0456 0.0033 0.0032
2.08% 2.08% 2.08% 1.42%
0.1324 0.1324 0.1324
air
加熱片面積 62.00mm×12.00mm，游標尺最小刻度 0.05mm
2
加熱片與室溫溫度差最大範圍 35.1－25.8=10.3℃，DA2500E 之準 確度為 0.1℃，平均溫差容許的誤差為 0.3℃
二 雷諾數之不準度分析
由式（3-2），無因次振動振幅Lc =lc/W
2
(3) 溫度差ΔTw之不準度:
加熱片與室溫溫度差最大範圍 35.7－25.8=10.3℃，DA2500E 之準確 度為 0.1℃，平均溫差容許的誤差為 0.3℃
當雷諾數 200，溫差(ΔT)=10℃時，取前段加熱區振動頻率
air in in lose lose
air air in air lose air air
air air
δQ Q Q Q Q Q Q Q Q
0.0005 0.0005
2.04 0.15
2 2 1 2
因此其不準度為
(vi) 巴沙木尺寸 62.00mm*12.00mm，游標尺最小刻度 0.05mm
(vii) 溫差最大範圍 45.775－44.875=0.9℃，DA2500E 之準確度為 0.1℃
(vii) 溫度差在 0.3℃之內皆視為等溫，故此項趨近於零。
2 2 2
2 2 2 1/ 2
0.306 0.0708 0.0004
0.33% 6.47% 2.08%
0.1852 0.1852 0.1852
0.0316 0.0132 0.0048
2.08% 2.08% 2.08% 0.95%
0.1852 0.1852 0.1852
air
加熱片面積 62.00mm×12.00mm，游標尺最小刻度 0.05mm
2
加熱片與室溫溫度差最大範圍 35.1－25.8=10.3℃，DA2500E 之準 確度為 0.1℃，平均溫差容許的誤差為 0.3℃
二 雷諾數之不準度分析
10 0.025 0.025
373 29.90 120.7
u
由式（3-2），無因次振動振幅Lc =lc/W
2
10 0.025 0.025
373 29.90 120.7
0
(3) 溫度差ΔTw之不準度:
加熱片與室溫溫度差最大範圍 35.7－25.8=10.3℃，DA2500E 之準確 度為 0.1℃，平均溫差容許的誤差為 0.3℃
10 0.025 0.025
373 29.90 120.7
0
附錄二
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附錄三
10 0.0749/0.2604
=28.76%
0.0587/0.1811
=32.41%
0.0508/0.1158
=43.87%
300
40 0.0801/0.3549
=22.57%
0.0691/0.2401
=28.78%
0.0511/0.1167
=43.86%
10 0.0708/0.306
=23.25%
0.0637/0.1842
=34.58%
0.0501/0.1155
=43.38%
200
40 0.0832/0.3258
=25.54%
0.0704/0.1985
=35.47%
0.0502/0.1207 41.6%
0.0441/0.1121
=39.34%
300
40 0.0809/0.3306
=24.47%
0.0697/0.1894
=36.81%
0.0446/0.1208
=36.92%
10 0.0781/0.3102
=25.18%
0.0698/0.1837
=38.00%
0.0387/0.1128
=34.30%
200
40 0.0787/0.3297
=23.87%
0.0752/0.1872
=40.17%
0.0467/0.1203 38.82%