laminar-turbulent transition 中文意思是什麼

laminar-turbulent transition 解釋
層流―紊流過渡段
  • laminar : adj. 由薄片或層狀體組成的，薄片狀的；層狀的。 laminar flow 【物理學】片流，層流。
  • turbulent : adj. 1. 激流的；湍流的。2. 騷亂的；強橫的。
  • transition : n 轉變，演變，變遷，變化；飛越；過渡期；【音樂】變調，轉調；【修辭學】語次轉變；【語法】轉換；【...
  1. The experimental results of the flow characteristics of the mmc heat sink indicate that the critical reynolds number signifying the transition from laminar flow to turbulent flow is in advance ; under the same experimental conditions, the variation in entrance direction of the microchannel inlet and outlet has little effect on the microchannel ; the experimental values of the friction factor of the de - ionized water in a microchannel agree well with those calculated using the theoretical laminar formula ; furthermore, a comparison of the experimental results and simulation results shows that navier - stokes equation and rng - turbulence model can be used to model the laminar and turbulence flow regions in a microchannel ; meanwhile, the correlations of the flow resistance in the turbulent flow regions for the de - ionized water as the working fluids are obtained from experiments

    對歧管式單通道熱沉流動特性的研究結果表明，微通道內流體流態由層流向紊流轉變的臨界雷諾數提前;改變流體的進出口方向對熱沉總壓降造成的影響很小;摩擦系數的實驗值與理論值較接近;數值模擬結果能夠與實驗值較好吻合;並由實驗給出了紊流區流動阻力的實驗關聯式。此外，選用十二烷基硫酸鈉（ sodiumdodecylsulphate ， sds ）以及烷基多糖苷（ alkylpolyglycoside ， apg ）作為減阻添加劑，研究了表面活性劑添加對微通道流動特性的影響。
  2. In the thesis the low drag - low noise optimization of the vehicle main form design is realized, main accomplishments are as follows. researched the knowledge of drag and flow noise, the parameters of the boundary layer are calculated by the hess - smith method and boundary layer momentum integral method. the calculation of the length of transition zone and change in boundary layer displacement thickness between laminar and turbulent states in the transition is improved, then the drag coefficient and self - noise from the transition zone are calculated as the objective functions of the optimization

    主要研究內容和成果如下：對航行器繞流流場進行分析，深入研究了阻力和流噪聲產生機理，建立了阻力系數和自噪聲的評估數值計算模型；採用物面分佈源匯法和邊界層動量積分法對繞流流場的流體動力參數進行計算，改進了轉捩區長度和邊界層位移厚度的計算，應用於航行器頭部駐點自噪聲的計算；最後設計了阻力系數和自噪聲數值計算程序模塊。
  3. All of the results indicated the turbulent boundary layer had been turned into the laminar layer. the skin friction coefficient drops rapidly. this result not only proved the phenomenon of reverse transition had occurred, but also showed that this condition was drag - reducing condition

    實驗結果表明板面附近的流動已由湍流流動轉變為層流流動，同時平板表面的摩擦系數較沒有溫度梯度時有大幅度下降，不僅證明了邊界層逆轉捩現象的存在，也說明了這種條件起到了減阻的效果。
分享友人
分享到 Line

分享到臉書