Calculating ylaminar, ybuffer and yturbulent using with Blasius Equation

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In summary, the conversation is about calculating the laminar, buffer, and turbulent boundary layers using the Blasius Equation. The person is asking for help on finding the expressions for these layers and how to determine the transition point. They also mention having tabulated data for Eta values from Rosenhead's book.
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firestarter7
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Calculating ylaminar, ybuffer and yturbulent using with Blasius Equation...

1. Homework Statement

How do you I calculate the Laminar Boundary Layer Y in meters with Blasius Equation?
I have an expression for U (m/s) and u/U and u(m/s) and also eta=0.1, 0.2...5.2. I am wondering how one could calculate the y laminar boundary layer (m), the y buffer boundary layer (m), the ln y and the y turbulent boundary layer (m)... I know that I need different expression to calculate these...can someone tell me what expressions and how I get the y laminar/buffer/ln y/y turbulent?

This is an example of the sheet I have:
U (m/s) u/U u (m/s) Eta y lam (m) y buff (m) ln y y turb (m)
252.7 0 0 0 ? ? ? ?
252.7 0.047 11.8 0.1 ? ? ?
252.7 0.0939 23.728 0.2 ? ? ? ?
etc...

2. Homework Equations

I do think I can use the equation

Eta= y*sqrt(U/nu*x)
for ylaminar...but I have already found the tabulated data for Eta from Rosenhead's book in Laminar Boundary Layers...and I have the following X values:
X=...
25.91
27.27
28.94
30.08
32.64
34.62
36.19
39.13
41.99
43.44
44.57
45
44.57
43.44
41.99
39.13
36.19
34.62
32.64
30.88
28.94
27.27
25.91

The following Eta values
h
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
2
2.2
2.4
2.6
2.8
3
3.2
3.4
3.6
3.8
4
4.2
4.4
4.6
4.8
5
5.2

and U=252.7 m/s and u/U accordingly.

3. The Attempt at a Solution
For ylaminar do I only solve for y in the equation Eta= y*sqrt(U/nu*x)?
If so, how what are the expressions for ybuffer, ln y (meaning which y should I take the log function on, the laminar, buffer or turbulent) and yturbulent? Can anyone pls help me? I am unsure about how to see when the transition starts so I can go from ylaminar to ybuffer/ turbulent based on my y values...I am grateful if anyone can help me. Thanks
 
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Why doesn't anybody even attempt to help me?
 

Related to Calculating ylaminar, ybuffer and yturbulent using with Blasius Equation

What is the Blasius Equation and how is it used in calculating ylaminar, ybuffer, and yturbulent?

The Blasius Equation is a mathematical equation used to calculate the boundary layer thickness of a fluid flow over a flat plate. It takes into account the viscosity and velocity of the fluid, as well as the distance from the leading edge of the plate. It is used to determine the values of ylaminar, ybuffer, and yturbulent, which represent the distances at which the flow changes from laminar to turbulent, from laminar to buffer, and from buffer to turbulent, respectively.

What factors affect the values of ylaminar, ybuffer, and yturbulent?

The values of ylaminar, ybuffer, and yturbulent are affected by the viscosity of the fluid, the velocity of the fluid, and the distance from the leading edge of the flat plate. They can also be affected by the surface roughness of the plate and any disturbances in the flow.

Can the Blasius Equation be used to calculate the boundary layer thickness for any type of fluid flow?

No, the Blasius Equation is specifically designed for laminar, incompressible flow over a flat plate. It may not be accurate for other types of flows, such as turbulent or compressible flows.

Are there any limitations to using the Blasius Equation in calculating ylaminar, ybuffer, and yturbulent?

Yes, the Blasius Equation assumes that the flow is steady, incompressible, and two-dimensional. It also does not account for any external forces acting on the flow, such as gravity or pressure gradients. Additionally, it may not be accurate for flows with high Reynolds numbers or for flows over non-flat surfaces.

How can the results from the Blasius Equation be applied in real-world situations?

The values of ylaminar, ybuffer, and yturbulent can be used in the design of various engineering systems, such as aircraft wings or heat exchangers. They can also be used to understand and predict the behavior of fluid flows in various applications, such as in pipelines or in the human body.

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