pyENL

(Python "Ecuaciones No Lineales")

^{A baby tiny open-source alternative to Engineering Equation Solver (EES)}

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Description

Engineering nonlinear equations systems solver

Features

• [x] Solve numerically systems equations from MINPACK method of SciPy.
• [x] More solvers available from: scipy.optimize.root
• [x] Physical units support
• [x] CoolProp thermodynamical functions support
• [ ] Engineering functions inside
• [ ] Users functions (Python).
• On development stage!

Use:

• Terminal mode:

  entrada.py -f file_text -t[seconds]:

  Equations file with conditions of each variable. Example:

  • x^2+y^2 = 1
  • y = 2*x - 5
  • {x, 1, -5, 5}

  In this case, the target is solve the equations in a file text with the following restrictions: x it's betweet -5 and 5, and the initial guess for x is 1.

  • Comments between symbols: "<<" and ">>"
  • Example: test/input2.xt
• GUI (User Interface):

File pyENL.py run the Qt interface for pyENL.

• Screenshots:

Thermodynamical properties

Via CoolProp, an open source thermodynamical properties library. Install:

pip install coolprop

• The pyENL function "prop" it's used for this purpose: CoolProp Documentation

• Example: Water enthalpy at atmosferic pressure and 300 K:

  prop('H', 'P', 101325, 'T', 300, 'Water')

Strings variables:

#ref# = 'R134a'

P = prop('P', 'T', 300, 'Q', 0, #ref#)

H = prop('H', 'P', P, 'T', 300, #ref#)

^{Icon by @fabianalexisinostroza}