针翅套管内强迫流动阻力特性试验研究

以润滑油-水为工质，对针翅套管双侧强迫流动的阻力特性进行试验研究，分析针翅相对高度与针翅管节距等因素对流动阻力系数的影响。结果发现，针翅套管环隙内的流动阻力特性与普通圆管以及光滑管环隙大不相同。由于其环隙内布满针翅，对流体产生了极大的扰动，因此对流体流态的转变有重要影响，其中相对翅高的影响较大。在对试验数据进行分析整理的基础上，回归出摩擦阻力压降与质量流速和针翅管结构参数的试验关联式。

Experimental Study on the Resistance Characteristics of Forced Convection in Pin-Fin Casing

A study is conducted on the resistance characteristic of forced convection in pin-fin casing, where both lubricants and water are used as test fluids. The effects of height and pitch of the pin-fin on the resistance coefficient are presented accordingly. The results show that the flow resistance characteristics of pin-fin casing annulus are quite different from that for both conventional circular tubes and smooth tube annulus. Particularly, the fluid in the annular space is significantly disturbed by pin-fin, the relative height of which exerts great impacts on the transition of fluid state. Also,the correlation of the frictional pressure drop is calculated by introducing the mass velocity and structural parameters of pin-fin tubes based upon experi-mental data,which facilitates further discussion on the resistance characteristic of pin-fin casing annulus.