近地面失速 的英文怎麼說
中文拼音 [jìndemiànshīsù]
近地面失速
英文
ground stall-
During winter nights and under clear skies, the ground surface is cooled rapidly by radiating heat off to space. the air temperature near the ground will also fall and when the grass temperature drops below zero degrees celsius, hoar frost will form by direct sublimation of water vapour onto the grass surface
在冬天的晚上，如果天氣晴朗，地面的熱量會透過輻射快速散失，貼近地面的空氣也同時降溫，當草面溫度降到攝氏零度以下時，空氣里的水蒸氣便會在草面凝華成為白茫茫的霜。The area of soil erosion in china has been increasing by 10, 000 square km. annually to 3. 67 million square km. at present, accounting for nearly 38 percent of the total land area
我國水土流失面積每年以10 ， 000平方公里的速度在擴大。目前，水土流失面積已達367萬平方公里，占總土地面積將近38 % 。The surface panel method has been applied to predict the hydrodynamic performance of highly skewed propeller. the surface of propeller and its trailing vortex are discreted by a number of small hyperboloidal quadrilateral panels with constant source and doublet distribution. for highly skewed propeller, the conventional method generating grid oriented along constant radii will result in a high aspect ratio and a high skewness and a twist panel near the propeller tip on blade surface, which result easily in incorrect calculation results of velovity on blade surface, even in iteration divergence and calculation failure. a “ non - conventional grid ” is developed to acoid these problems. this grid can effectively solve the problem of the calculation and convergence for highly skewed propeller. the non - linear kutta condition of equal pressure on upper and lower at the trailing edge is executed by the iterative procedure. by sample calculating, the obtained results are satisfied the experimental data
採用面元法預報大側斜螺旋槳水動力性能，螺旋槳表面及尾渦面離散為四邊形雙曲面元，每個面元上布置等強度源匯和偶極子分佈.對于大側斜螺旋槳而言，槳葉表面採用常規的等半徑網格劃分方法在近葉梢處將導致大展弦比、大側斜和扭曲面元，這容易使槳葉表面速度的計算結果不正確，甚至會導致迭代過程發散及計算失敗.文中建立了一種「非常規網格」劃分方法，能有效地解決大側斜螺旋槳的計算和收斂問題.槳葉隨邊處通過迭代實現非線性等壓庫塔條件In recent years, the screw pump gets more and more extensive application with its unique performance in the oil field, in order to improve the output of crude oil, we should select pump of big displacement or increase the rotational speed, but this will make the ground system vibrate seriously, causing the system to be unable to work normally or some spare parts lose efficiency too early
近年來，在油田現場螺桿泵以其獨特的性能得到越來越廣泛的應用，為了提高原油產量，當選用大排量螺桿泵或增加螺桿泵的轉速時，地面驅動系統將產生強烈的振動，導致系統無法正常工作或系統內的某些零部件過早失效。分享友人