pydrying 1.0.4

Drying simulation of solid products

Welcome to pydrying module!

pydring is a Python package intended to simulate the drying process. The simulation programs in this module are based on multiphysical and dynamic modeling of the drying phenomena (heat, mass & momentum transfer, and deformation of the drying product). The resolution of drying equations is based on the numerical method of finite volumes. This module calculates the drying kinetics of any solid product. The modeling of drying kinetics is essential in most transformation processes, such as the food industry (sugar industry, biomass refinery, fodder processing, etc.)

Installation

WaterOptim runs under Python 3.6+. To install it with pip, run the following: pip install pydrying To upgrade it with pip, run the following: pip install --upgrade pydrying

Basic usage

Thermophysical properties of drying material

from numpy import ones,exp
from pydrying.dry import thin_layer, material
# diffusion coeff in the material
def Diff(T,X):
"""
Parameters
----------
T : Temperature [°C]
X : TYPE
    moisture content [dry basis]
Returns
-------
Diffusion coefficient [m2/s]
"""
    return 1e-9*ones(len(T))
# sorption isotherms
def aw(T,X):
"""
Parameters
----------
T : Temperature [°C]
X : TYPE
    moisture content [dry basis]
Returns
-------
water activity of the drying material [decimal]
"""
    return (1.0-exp(-0.6876*(T+45.5555)*X*X))
# thermal conductivity of the drying material
def Lambda(T,X):
"""
Parameters
----------
T : Temperature [°C]
X : TYPE
    moisture content [dry basis]
Returns
-------
thermal conductivity [W/m/K]
"""
    return .02

Geometric properties

material_shape = 0 # flat material, (1: cylinder, 2: sphere)
caracteristic_length = 1e-2 # m

Drying conditions

drying_time = 3600 # s
heat_transfer_coefficient = 25 # W/m2/K

Drying air properties (pressure, temperature and relative humidity) can be set from python calss air.

Definition of drying material

drying_material = material(Diff=Diff,aw=aw,Lambda=Lambda,
                           m=material_shape,
                           L=caracteristic_length,)

Solve the problem of thin layer drying

problem = thin_layer(material=drying_material,air={},
h=heat_transfer_coefficient,
tmax=drying_time)
problem.solve()

Water content plot

	import matplotlib.pyplot as plt
	plt.plot(tl.res.t, tl.res.Xmoy())
	plt.xlabel("drying time in s")
	plt.ylabel("moisture content in dry basis")

Plot of material surface temperature

	plt.plot(tl.res.t, tl.res.T[-1,:])
	plt.xlabel("drying time in s")
	plt.ylabel("material temperature in °C")