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8-Gravel
May 3, 2022
Solved

From set of equations with trigonometric functions to one single equation

  • May 3, 2022
  • 2 replies
  • 2531 views

I have a set of 4 equations which are used to determine the relation between Bèta and Delta_L.

Now I have to generate a list of values for alpha and through x2' and beta + y2' I am able to calculate Delta_L. For any value of Delta_L I then need to interpolate to get to the approximate solution. I would however prefer to have a direct correlation between Delta_L and Bèta without alpha (if possible of course). Thought the symbolic engine might be able to help but to be honest it's been a while since I last used it so I'm stuck.

 

I have attached the formulas in the attached calculation sheet.

 

Any help is kindly appreciated.

 

Best answer by Werner_E

So here is the worksheet with the functions made dependable on r and L3 and also using L2=L3+r as you amended

Werner_E_0-1651655011865.png

 

2 replies

21-Topaz II
May 4, 2022

Hi,

Here is my engineering accuracy solution.

Cheers

Terry

8-Gravel
May 4, 2022

Hello Terry,

 

thanks a lot for your solution.

I did forget to mention that we want to be able to alter "r" as well. Your solution does make it possible to generate a formula for any different value but ideally we would have a plc programmable equation that makes it possible to calculate D_L for any given value of b (within 0 to p/2 range) and r (within 50 to 85 range).

Like I said before, no idea whether that's even possible or not.

 

Found out by altering the "r" in your sheet that I had missed another relation: L2=L3+r

I replaced L2 in all formulas now by L3+r so it's no longer a variable

25-Diamond I
May 4, 2022

The symbolic was not of much help in finding a alpha for any given beta.

Fortunately a  numeric approach using a solve block or the root function is all that is needed.

Here is DeltaL as a function of beta:

Werner_E_0-1651653283465.png

Of course you can make all functions also dependable of the three input values r, L2 and L3 for more flexibility, as Terry had shown in his approach.

 

 

Werner_E25-Diamond IAnswer
25-Diamond I
May 4, 2022

So here is the worksheet with the functions made dependable on r and L3 and also using L2=L3+r as you amended

Werner_E_0-1651655011865.png