1. PF Contest - Win "Conquering the Physics GRE" book! Click Here to Enter
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Blasius Equation Program

  1. Nov 10, 2009 #1
    1. The problem statement, all variables and given/known data

    I am trying to write an excel spreadsheet to show the f, f', f'', and f''' for [tex]\eta[/tex] = 0 - 8.8 and I just wanted to check my formulas if someone wouldn't mind as my results are slightly off from the tables in my fluid mechanics book

    2. Relevant equations


    [tex] f''' + \frac {1}{2} f f''' = 0 [/tex]

    Boundary Conditions:

    [tex] f(0) = f'(0) = 0 [/tex]

    [tex] f'(\eta \rightarrow \infty) = 1 [/tex]

    [tex] \Delta\eta = 0.2 [/tex]


    [tex] f_{i2} = f_{i1} + \Delta\eta * \frac {f'_{i1} + f'_{k1}} {2} [/tex]

    [tex] f'_{i2} = f'_{i1} + \Delta\eta * \frac {f''_{i1} + f''_{k1}} {2} [/tex]

    [tex] f''_{i2} = f''_{i1} + \Delta\eta * \frac {f'''_{i1} + f'''_{k1}} {2} [/tex]

    [tex] f'''_{i2} = -\frac {1} {2} f_{i2} * f''_{i2} [/tex]


    [tex] f_{k2} = f_{i2}+ \Delta\eta * f'_{i2}[/tex]

    [tex] f'_{k2} = f'_{i2}+ \Delta\eta * f''_{i2}[/tex]

    [tex] f''_{k2} = f''_{i2}+ \Delta\eta * f'''_{i2}[/tex]

    [tex] f'''_{k2} = -\frac {1} {2} f_{k2} * f''_{k2} [/tex]

    3. The attempt at a solution

    Thanks in advance!

    Just a note, I couldn't get i-1 and k-1 subscripted, so i2, k2 is current and i1, k1 is the previous result. Initial boundary conditions are set at i0, for f, f', f'', and f'''.
  2. jcsd
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted

Similar Threads - Blasius Equation Program Date
Proving a wave satisfies the Helmholtz equation Yesterday at 12:29 AM
Question on correctly interpreting a bra-ket equation Saturday at 6:17 PM
Solving For an Equation Wednesday at 8:12 PM
Deriving Thick lens Equation Mar 10, 2018
Physics Of A Loop Using the Program "Tracker" Nov 8, 2017