Turbomachinery - change rotation every 30 timesteps (CEL)

lindner · September 2, 2011, 13:51

Hi,
The title gives a hint, i need to change the rotation of my machine every 30 timesteps, increasing in 10 rpm.
Example: Iteration 1 angular velocity = 120
Iteration 30 angular velocity = 120+10
Iteration 60 angular velocity = 120+10+10
I tought something like this
if(citern=30, AngVel=AngVel+10)
if(citern=60, AngVel=AngVel+10) ...

I never programmed in CEL, so i don't know all the options to script that.
Anyone have an ideia to make this as simple as possible?

Thanks in advance

ghorrocks · September 2, 2011, 18:36

You could write this function using the mod function in CEL, or you could define a 1D interpolation function.

lindner · September 6, 2011, 07:03

Thanks ghorrocks, i will try this mod function and post the results later.

lindner · September 6, 2011, 08:27

ok, now my rotation speed increases every 30 iterations, see above.

rot = 120 [rev min^-1]
rotVar = rot + r1*yy+r2*yy+r3*yy
r1 = if(citern>=30,1,0)
r2 = if(citern>=60,1,0)
r3 = if(citern>=90,1,0)
yy = 10 [rev min^-1]

Is it possible to make the variable dependent on the RMS residuals instead of iterations? Like if (RMS<0.0001,1,0)
What should be in the place of RMS variable?

thanks

ghorrocks · September 6, 2011, 18:56

I don't think the RMS residuals are a CEL variable, so I don't think you have access to it.

September 2, 2011, 13:51	Turbomachinery - change rotation every 30 timesteps (CEL)	#1
lindner Member Join Date: Mar 2010 Posts: 42 Rep Power: 16	Hi, The title gives a hint, i need to change the rotation of my machine every 30 timesteps, increasing in 10 rpm. Example: Iteration 1 angular velocity = 120 Iteration 30 angular velocity = 120+10 Iteration 60 angular velocity = 120+10+10 I tought something like this if(citern=30, AngVel=AngVel+10) if(citern=60, AngVel=AngVel+10) ... I never programmed in CEL, so i don't know all the options to script that. Anyone have an ideia to make this as simple as possible? Thanks in advance

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September 2, 2011, 18:36		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	You could write this function using the mod function in CEL, or you could define a 1D interpolation function.

September 6, 2011, 07:03		#3
lindner Member Join Date: Mar 2010 Posts: 42 Rep Power: 16	Thanks ghorrocks, i will try this mod function and post the results later.

September 6, 2011, 08:27		#4
lindner Member Join Date: Mar 2010 Posts: 42 Rep Power: 16	ok, now my rotation speed increases every 30 iterations, see above. rot = 120 [rev min^-1] rotVar = rot + r1yy+r2yy+r3*yy r1 = if(citern>=30,1,0) r2 = if(citern>=60,1,0) r3 = if(citern>=90,1,0) yy = 10 [rev min^-1] Is it possible to make the variable dependent on the RMS residuals instead of iterations? Like if (RMS<0.0001,1,0) What should be in the place of RMS variable? thanks

September 6, 2011, 18:56		#5
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,700 Rep Power: 143	I don't think the RMS residuals are a CEL variable, so I don't think you have access to it.