Download presentation
Presentation is loading. Please wait.
Published byShawn Wright Modified over 9 years ago
1
Cost-effectiveness: An Engineers's Real Job Problem 3.138* Created By: Patrick Thomas
2
Problem A pitot-static probe to measure the velocity distribution in a water tunnel at 20 o C. U-tube manometer that uses a liquid of specific gravity 1.7. Maximum velocity= V max = 2.3 m/s. U-tube manometers to choose from are 8, 12, 16, 24, and 36 inches, with increasing cost (respectively). Which U-tube manometer should be purchased?
3
Assumptions Incompressible flow One-dimensional flow Steady flow
4
Important Formulae The Pitot Formula: Hydrostatic Relationship for Manometer Specific gravity Specific Weight
5
Calculations Using the rearranged Pitot Equation, we can solve for the pressure difference: With the pressure difference and specific weight, we can solve for the displaced liquid using the hydrostatic equation:
6
Discussion Although an 8 inch manometer would suffice, I suggest purchasing a 12 inch manometer (for a factor of safety of 2).
7
Relation to Biofluids The pitot-static probe measures slow moving fluids well. Thus, the pitot-static probe would make a great blood pressure measurement device. The pitot-static probe runs into problems when the flow is not laminar, however.
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.