azogue / psychrochart

A Python 3 library to make psychrometric charts and overlay information on them.
MIT License
104 stars 27 forks source link

Error for plotting enthalpy lines above 500 kJ/kg #22

Closed Remaster3Pi closed 1 year ago

Remaster3Pi commented 2 years ago

Hello, I am using this for project that is not HVAC related. The operating points are hotter and higher humidity than any HVAC system. Upwards of 90C with RH of 90%.

When plotting for an enthalpy exceeding 500 kJ/kg, I receive this error: ERROR:root:ENTHALPHY CONVERGENCE ERROR: No convergence error after 100 iterations! Last value: 61.13422132911032, ∆: 0.001. Objective: 500, iter_value: 499.98766076525493 This happens regardless of the Max number of iterations or precision values. The change I make in the script do not appear to have an effect (I did turn some other features on/off to verify I was modifying the correct file. If I change the max Enthalpy value to 500 or below, I do not receive this error and the constant enthalpy lines below 500 do plot just fine. Is there something in the code limiting this (I can't seem to find anything though) or is the psychrolib limiting the max enthalpy somehow (again I can't seem to find something limiting this).

Thank you, Roy image image

azogue commented 1 year ago

Hi @Remaster3Pi 👋,

Sorry for the long delay in replying 🙏, I had totally forgotten about this library, for years (and had GH notifications muted 🙈)

If you are still interested, the convergence errors for constant enthalpy curves should be solved after #32. Check the releases 😜

I am using this for project that is not HVAC related. The operating points are hotter and higher humidity than any HVAC system. Upwards of 90C with RH of 90%.

Take into account the NOTE in the README about limits and expected fidelity for the calculations done with the library. It may not match your requirements 🙈