Calculating ylaminar, ybuffer and yturbulent using with Blasius Equation

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To calculate the laminar boundary layer (ylaminar) using the Blasius Equation, the expression Eta = y * sqrt(U/nu*x) can be rearranged to solve for y. The user has tabulated values for Eta and X, which can be utilized to derive ylaminar for various conditions. For the buffer layer (ybuffer) and turbulent layer (yturbulent), additional expressions are needed, but the user is unclear on what these are and how to transition between layers based on y values. Clarification is sought on which values to use for calculating the logarithmic value (ln y) and the criteria for transitioning from laminar to turbulent flow. The discussion highlights the need for guidance on these calculations and expressions.
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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?
 

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