Sizes speed through pipes

Underflow Dams, While mechanical boom, pneumatic barriers, and water jet systems may be adapted to almost any size of waterway, a number of simple confinement methods, such as the underflow dam, are best suited to smaller waterways. As shown in Figure 13.3, an underflow dam uses a series of pipes extending through an earthen harrier to confine a floating spill. The pipes allow water to pass through the barrier, and when the pipes are positioned with the upstream end lower than the downstream end, the water level is raised above the intake of the pipes and the floating spill is retained. In order to control the flow of water, a sufficient number of pipes must be installed in the dam. The width, depth, and speed of the water can be used to calculate the flow rate and thus determine the number of pipes that need to be used. The use of elbows on the upstream end of the pipes will help prevent the formation of a vortex that can sometimes occur, pulling surface material down... 

The high-inertia reactor coolant pumps are highly reliable, low-maintenance, hermetically sealed pumps, which circulate the reactor coolant through the reactor core, loop piping, and steam generators. The motor size is minimized through the use of a variable speed controller to reduce motor power requirements during cold coolant conditions. 

In such (wed) mass transfer, it is carried out only through a surface of a film of the liquid current on a contact branch pipe(Figure 15.4). The attitude relation of this surface to the chaige of an easy phase at the set speed is proportional to size H/D of a contact branch pipe with which increase efficiency mass transfer increases, but thus specific metal consumption (cd) raises increases also. 

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