Water at atmospheric pressure and temperature
(a)
The Reynolds number based on cylinder diameter.
Answer to Problem 69P
The Reynolds number is
Explanation of Solution
Given information:
The density of fluid is
Write the expression of the Reynold number.
Here, the density of the fluid is
Calculation:
Substitute
Thus, the value of Reynolds number is very high. So, the approximation of potential flow is reasonable.
Conclusion:
Thus the Reynolds number is
(b)
The minimum speed.
The maximum speed.
The maximum pressure difference.
The minimum pressure difference.
Answer to Problem 69P
The minimum speed is
The maximum speed is
The maximum pressure difference is
The minimum pressure difference is
Explanation of Solution
Given information:
Write the expression of minimum speed.
Here, the speed at stagnation point is
Write the expression of Bernoulli's equation at the stagnation point.
Here, the pressure at starting is
Write the expression of maximum speed.
Here, the free stream velocity is
Calculation:
The speed at stagnation point is
Therefore, the minimum speed is
Substitute
So, the maximum pressure difference is
Substitute
So, the maximum speed is
Substitute
So, the minimum pressure difference is
Conclusion:
The minimum speed is
The maximum speed is
The maximum pressure difference is
The minimum pressure difference is
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