24小时热门版块排行榜    

查看: 293  |  回复: 0

hieyo224

木虫 (正式写手)

[求助] 求助传递现象题目,请告诉我解题思路

1.
Hydrogen diffuses through a .5 cm thick stagnant water film. How many grams of hydrogen diffuses through a 1 m**2 area in one day? Assume D = 50E-6 cm**2/sec, inlet concentration of 5.2E-3 gm/cc, and outlet concentration of 2.0E-3 gm/cc.

2.
A horizontal bar with constant cross section of 2 cm**2 has variable conductivity with k1 = 10 W/(m K) in the first 5 cm, k2=60 W/(m K) in the next 8 cm, and k3=15 W/(m K) in the final 12 cm. On the edge of region 1, the temperature is fixed at 100 C. On the far end of region 3, the ambient temperature is 40 C with a convection coefficient of 5 W/m**2. What is the temperature in the middle of region 2?

3.
Water drains from a pond through a 15 foot sand channel with a 1 ft**2 cross sectional area, and permeability of 2.0 darcies. If the pressure head is maintained at 15 psig at the inlet of the channel, and the outlet is at atmospheric pressure, and assuming water density of 62.4 lbm/ft**3, and viscosity of 1cp, what is the total volume in ft**3 that has drained in 2 hours?

4.
A funnel is packed with fine-grained sand, so that the sand pack has a permeability of 100 md. The area varies linearly from 6 cm**2 to 3 cm**2 over a distance of 12 cm. If the pressure at the small area is 0 psig, and the pressure is 13 psig at the face of the large area, what is the pressure in psig halfway between ends? The fluid flowing is water with density of 1000 kg/m**3 and viscosity of 1.0 cp.
回复此楼
已阅   回复此楼   关注TA 给TA发消息 送TA红花 TA的回帖

智能机器人

Robot (super robot)

我们都爱小木虫

相关版块跳转 我要订阅楼主 hieyo224 的主题更新
信息提示
请填处理意见