Calculation problems
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The pipe specification is φ108×4, and the medium flow rate is 150 cubic meters per hour; therefore, the flow velocity is ( )m/s. A、 5.408 B、 5.308 C、 4.907 D、 4.551 What does B φ108×4 mean, and how is it calculated?
This post was last edited by ylb913 on 2016-9-3 21:07. The unit of flow rate is “meters per second”. The flow rate is 150 cubic meters per hour; divided by 3600 seconds per hour, this equals 0.0417 cubic meters per second. The inner diameter of the pipe is 108 – 4×2 = 100 mm, which is equivalent to 0.100 meters, while the radius is 0.05 meters. The cross-sectional area of the pipe is 0.05×0.05×3.14 = 0.00785 square meters ； 0.0417÷0.00785=5.308 meters/second
It’s the same as the question you asked just now; take a good look at the basic knowledge of chemistry
B, 5.308； φ108×4 has an outer diameter of 108 mm and a wall thickness of 4 mm. Calculation method: Flow rate divided by the pipe cross-sectional area.
The pipe specifications are φ108*4, where φ108 represents the outer diameter of the pipe and 4 represents the wall thickness. The inner diameter of the pipe is therefore 108–4*2=100. It is this inner diameter that serves as the parameter for calculating the flow velocity; the calculation method has been provided by the person above