Introductory Fluid Mechanics L14 p1 - Dimensional Analysis

[mattb]

Thank you so much for these videos! I wish I had found them at the beginning of the semester. I'll be frequenting your heat transfer videos next semester!

[mohamedboujnah]

How can he be this good at explaining stuff !
Thanks a lot sir

[baskarasabesanniroshan]

Fluid mechanics utilizes methods such as differential and integral analysis, dimensional analysis, computational fluid dynamics, and experimental techniques for analysis.

[asmrteenboy]

Iam from india and this series is very useful

[hamdimohamed]

I love you so much. Thank you for sharing this.

[alexwalton]

i got some questions to ask if you could do a video it would help
1)
An ideal gas enters a nozzle with negligible velocity and specific enthalpy h1 = 2, 506 kJ/kg at the inlet. It leaves the nozzle with a velocity of c2 = 516 m/s. Neglecting the heat transfer and changes in potential energy, calculate the specific enthalpy at the outlet h2 in the unit of kJ/kg.
2)
A door in the side of a tank is 4.0 m wide and 5.0 m high the tank is filled with oil of relative density 0.72 to a position 1m above the top of the door. What is the line of action of the force from the surface in meters.
3)
A door in the side of a tank is 2.1 m wide and 4.3 m high, the tank is filled to the top of the door with water of density 1000kg/m3.  What is the force on the door in N?
4)
Water flows through a pipe 4cm in diameter and 38m long between two tanks with square edged non projecting entrance and exit.  The flow rate is controlled by a gate valve which when fully open has a loss factor of 0.32.  What is the height difference between the tanks if the volume flow rate is  3.8 x10-3 m3/s.
For laminar flow f=16/Re
For turbulent flow f=0.08/Re0.25
Density of water,  
ρ
, is 1000kg/m3, viscosity of water,  
μ
, is 0.001Pa.s.
5)
The viscous torque produced on a disc rotating in a liquid depends upon the diameter D, the speed of rotation N, the density 
ρ
 and the viscosity 
μ
.  The equation taking the form:-
T = ρ N 2 D 5 φ ( ρ N D 2 μ )
In order to predict the torque on a 1.8 diameter disc rotating in water of density 1000kg/m3 at 129 rev/min a model is built to a scale of 1/4.  The model is rotated in oil. Calculate the speed of rotation, in rev/min, for the model to produce dynamic similarity.
The oil density is 785 kg/m3 and the dynamic viscosity of the oil is 4.7 x 10-4Pa.s.
The water dynamic viscosity is 1 x 10-3Pa.s.

[patricksawyer]

I think there was a mistake in calculating the number of tests required. Unless I misunderstood, we are testing 10 different diameters, 10 different viscocities, 10 different velocities, and 10 different densities with the other 3 variables held constant for each set of 10 experiments. That would mean 10*4=40, not 10^4=10, 000, experiments need to be performed. Further, even if we did each experiment with each of the 10 diameters, viscocities, velocities, and densities, that would be 10*10*4=400 since each parameter would have 100 (or 10*10) tests times 4 parameters. Or have I misunderstood the statement about how the testing is performed?

[Peter_]

9:55
"This is not efficient."

Ron Hugo disapproves.