Problem 7: During a storm, a snow drift is formed behind a snow fence as shown in the figure below. Assume that the height of the drift, h, is a function of the number of inches of snow deposited by the storm, d - the width of the slats (see figure); H - height of the fence; b - the distance between the slats; V - wind speed; g - acceleration of gravity; - air density; and Ys - specific weight of snow. This problem is studied with a model.
Fence
Drift
H
Select H, g, Ys as a set repeating variable and find the pi terms.
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EM 3201 Final Exam: Practice Problem Bank
a) Write out your PI terms and fill out the table below. (Not necessary to show all the details of the repeating variable procedure)
Variable Units Ti h L d L H L none b L V LTI g LT2 none FL-T Ys FL-3 none
b) Write a general form for the general prediction functions
Ysm = Ysp
d) A storm with winds of 42.5 mph deposits 16 in. of snow, a -sized scale model of snow is to be used to investigate the effectiveness of a proposed snow fence, determine the required wind speed for the model.
