CAJ | 학술논문

通过实验研究中心截面沿主流方向带有均匀加热平板的矩形通道混合对流入口段的阻力特性，得到Re数、Gr^＊数和倾斜角度对阻力系数的影响。实验结果表明：阻力系数随倾斜角度｜θ｜的增大而增大，在RP数的不同范围内呈不同的特性。Re数小于1500时，阻力系数随Re数的增大而减小，随G^＊数的增大而增大。当Re大于1500时，阻力系数受Re数和G^＊数的影响很小。综合考虑JRP数、Gr^＊数、倾斜角度及管道长径比的影响，对Re数大于1500和小于1500分别给得出了阻力系数的关联式，该组关联式与实验数据吻合良好，偏差小于10％。
통과실험연구중심절면연주류방향대유균균가열평판적구형통도혼합대류입구단적조력특성，득도Re수、Gr^＊수화경사각도대조력계수적영향。실험결과표명：조력계수수경사각도｜θ｜적증대이증대，재RP수적불동범위내정불동적특성。Re수소우1500시，조력계수수Re수적증대이감소，수G^＊수적증대이증대。당Re대우1500시，조력계수수Re수화G^＊수적영향흔소。종합고필JRP수、Gr^＊수、경사각도급관도장경비적영향，대Re수대우1500화소우1500분별급득출료조력계수적관련식，해조관련식여실험수거문합량호，편차소우10％。
The flow resistance characteristic of the entrance region of mixed convection in rectangular channel was studied by the experiment of the air flowed through a rectangular duct with a uniformly heated plate in the middle section. The rules of the friction factors variation connected with the Reynolds number, the Grashof numbers and inclination angles were obtained. The results reveal that when Re is less than 1 500, the friction factor increases with Re and decreases with Gr＊. Moreover, when the Re is greater than 1 500, the friction factor is little affected by Re and Gr＊. Furthermore, the friction factor increases with inclination angles. Considering the influences of Re, Gr＊, inclination angle and length to diameter ratio, correlations of friction factors were fitted when Re was greater or less than 1 500. Comparison of the friction factors calculated from the fitted correlations and the experimental results satisfactory reached agreement, with the deviations being less than 10%.