(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

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. Relevant 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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# How do you I calculate the Laminar Boundary Layer Y in meters

Can you offer guidance or do you also need help?

**Physics Forums | Science Articles, Homework Help, Discussion**