search

ibell / pdsim

Steady-State simulation code for positive displacement machines
MIT License
38 stars 23 forks source link

Enable multiple lumped temperatures in the overall energy balance #21

Closed davideziviani closed 4 years ago

davideziviani commented 8 years ago

Allow to include detailed equivalent thermal resistances between different lumped elements especially for hermetic compressors. Example Chen PhD on scroll

ibell commented 8 years ago

It's a good idea and should be mostly (completely?) implemented already. What happens when you try to use multiple lumps? Do you get an error?

On Mon, Jun 27, 2016 at 9:11 AM, dziviani notifications@github.com wrote:

Allow to include detailed equivalent thermal resistances between different lumped elements especially for hermetic compressors. Example Chen PhD on scroll

— You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub https://github.com/ibell/pdsim/issues/21, or mute the thread https://github.com/notifications/unsubscribe/ABxha3kU_-w_tWyBMlNvm_M-5ui_iJv1ks5qP-gagaJpZM4I_Mkv .

davideziviani commented 8 years ago

I looked at the code and it should be straightforward. Since we do not have an example of that capability, I plan to add it as I am working on a recip compressor and the detailed motor model is also available.

davideziviani commented 8 years ago

Today I was trying to work on the multiple lumps as I wanna include this part into the second paper about PDSim. I found out there is an issue with assigning the number of lumps as well as the number of residuals (or equations) required. I am going to leave a comment at the proper line.

davideziviani commented 8 years ago

The number of lumps need to match the number of residuals. In the current examples (recip,scroll, etc), lump_energy_balance_callback(self) returns a single residual. So I tried to add two lumps (self.Tlumps[0], self.Tlumps[1]) and two residuals, but list index is out of range for self.Tlumps even if I pass a guess array x0 to self.solve( )

I think here we need to generalize the structure to append multiple [self.Tlumps, self.lumps_resid].

I will be working on this issue. let me know if you see a better way of handling this issue.

davideziviani commented 7 years ago

It works fine at the moment also for speed. I am going to check if I need to implement a different algorithm besides Multi-Dim Newton Raphson.

davideziviani commented 4 years ago

Solved in #39