Measurements of the Heat and Mass Transfer Parameters Characterizing Conical Graupel Growth
Measurements of the Heat and Mass Transfer Parameters Characterizing Conical Graupel Growth
复制标题
表征锥形霰粒生长的传热传质参数的测量
DOI：
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发表时间：
1993
期刊：
影响因子：
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通讯作者：
R. List
中科院分区：
文献类型：
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作者：
S. Cober;R. List
摘要在风洞中，从1 mm的六边形平板开始，在液态水含量为0. 5 ~ 3. 0 g m-1，速度为1. 1 ~ 3. 0 m s-1，环境温度为-4. 4 ~-20. 9 °C，云滴中值体积半径为12 ~ 21 μm，环境压力为100 ~ 60 kPa的条件下，生长了刚性悬浮的圆锥形。选择生长条件来模拟自然条件下，圆锥形的生长，并作为冰雹的胚胎。最后的霰直径范围从1.5至6毫米，雷诺数在300和1500之间。测量的质量，体积，生长高度，几何形状，和表面温度随时间的推移被用来计算Nusselt和舍伍德数（代表对流传热和传质），散装收集效率，吸积密度。体收集效率和努塞尔数的斯托克斯参数和雷诺数，分别进行了参数化。密度和锥角以相对梯度的形式进行参数化。
Abstract Rigidly suspended conical graupel were grown in a wind tunnel, starting from 1-mm hexagonal plates, with liquid water content varied from 0.5 to 3.0 g m−1, velocity from 1.1 to 3.0 m s−1, ambient temperature from −4.4 to −20.9°C, cloud droplet median volume radius from 12 to 21 μm, and ambient pressure from 100 to 60 kPa. Growth conditions were chosen to simulate natural conditions in which conical graupel grow and serve as embryos for hail. Final graupel diameters ranged from 1.5 to 6 mm, with Reynolds numbers between 300 and 1500. Measurements of the mass, volume, growth height, geometric shape, and surface temperature with time were used to calculate the Nusselt and Sherwood numbers (representing the convective heat and mass transfers), bulk collection efficiency, and accretion density. The bulk collection efficiency and Nusselt number were parameterized in terms of the Stokes parameter and Reynolds number, respectively. The density and cone angle were parameterized in terms of the relative gr...