A water supply agency is planning to add two reservoirs to its system. Water will flow from Reservoir A to Reservoir B via a 10,
000-ft-long, 24-inch diameter steel pipe. The pipe will be installed beneath a road between the two reservoirs. The road crosses over a hill with a summit elevation of 375 ft above MSL. This summit is at a distance of 3000 ft from reservoir A.The elevation of the water surface in reservoir A will vary between 348.0 and 362.0 ft above MSL and the water surface in reservoir B will vary between 244.1 and 255.4 ft above MSL.Assume a temperature of 50°F. Neglect minor losses. Use a Hazen-Williams friction factor of 100 and an equivalent sand grain roughness of 0.060 in. These values are from Table 12.1.1 in the text.(a) Make a sketch that defines the geometry of the problem. Clearly label dimensions.(b) Determine which water level combination will lead to maximum discharge in the pipe and which water level combination will lead to minimum discharge in the pipe. This should be done by analyzing the relevant equations without doing any calculations. Show your work and explain your logic.
1 answer:
You might be interested in
Answer:
the heat transfer from the pipe will decrease when the insulation is taken off for r₂<
where;
r₂ = outer radius
= critical radius
Explanation:
Note that the critical radius of insulation depends on the thermal conductivity of the insulation k and the external convection heat transfer coefficient h .
The rate of heat transfer from the cylinder increases with the addition of insulation for outer radius less than critical radius (r₂< ) 0, and reaches a maximum when r₂ =
, and starts to decrease for r₂<
. Thus, insulating the pipe may actually increase the rate of heat transfer from the pipe instead of decreasing it when r₂<
.