f-number中文意思是什麼

Deng x g, zhuang f g, mao m l. on low mach number perfect gas flow calculations [ r ], aiaa paper 99 - 3317

鄧小剛.粘性超聲速復雜氣動力干擾的數值模擬[ d ] : [博士學位論文] ，中國空氣動力研究與發展中心， 1991

4 ) the number and mass concentration distributions of the background atmospheric sand particles of ymchuan, bayanhot and tonggunur display a unimodal form, obeying a logarithmic normal distribution, greatly differing f

黃沙的長距離輸送和小雨是泥雨形成的原因。雲物理和降水與來自沙塵粒子混合，尤其是小於zpm的粒子，導致了華北地區泥雨的發生。

For a - early f type ms stars, stellar chromospheric activity decrease with stellar rotation period, but increase with rossby number ; for m type ms stars, stellar chromospheric activity increase with stellar rotation period and rossby number, and stellar chromospheric activity reach saturation at large color index ; for the ms stars between mid - f to m type, stellar chromospheric activity decrease with stellar rotation period and rossby number

A ?早f型主序恆星的自轉周期和恆星對流區的隨色指數的分佈明顯地影響著這些恆星的色球活動行為。而m型主序星的色球活動水平基本上隨自轉參量的增大呈上升趨勢，並且m型主序星的色球活動水平在色指數較大時趨于飽和。

In this paper, by checking up the heat calculation about the experiment results of the single row tube and double waves belt, i come at the function of the heat transfer factor j and the reynolds number re, i also come at the function of the f r i ct i on factor ^ " and the reyno i ds number re

本文還通過對單排雙波帶散熱器的實驗結果進行校核熱計算，回歸導出該種散熱器的傳熱因子j及摩擦因子f與雷諾數re的數學表達式，從而為用這種芯子根據廠家要求設計散熱器提供了理論依據。

The weir wed packing with high number of theoretical stages and minimum pressure drop permetre. small hold - up, most economical load range : f factor 1. 52m skg m3. minimum liquid load approx : 0. 2 m3 m2h

該填料每米有較高的理論板數，每米填料的壓降低，持液量低，最佳的負荷因子1 . 52m s根號kg m