mirror of
https://github.com/ParticulateFlow/CFDEMcoupling-PFM.git
synced 2025-12-08 06:37:44 +00:00
6e71533e60
fix number of headerlines expected in probe files for ErgunTestCG, ErgunTestMPI_cgs and ErgunTestMPI_restart
116 lines
3.5 KiB
Matlab
116 lines
3.5 KiB
Matlab
close all;
|
|
clear;
|
|
clc;
|
|
|
|
%====================================%
|
|
% simulation data 1
|
|
%====================================%
|
|
rhoG = 10 % density in kg/m3
|
|
%path = '../probes/0/p'; % 2.1.x
|
|
path = '../postProcessing/probes/0/p'; % 2.2.x
|
|
columns=22;
|
|
headerlines=23;
|
|
data = loaddata(path,columns,headerlines);
|
|
data=transpose(data);
|
|
[x,y]=size(data)
|
|
dp_sim = (data(:,2)-data(:,y))*rhoG; % conversion to Pa
|
|
t_sim = data(:,1);
|
|
%fprintf('final pressureDrop of sim = %f Pa\n',dp_sim(length(dp_sim)) )
|
|
|
|
%====================================%
|
|
% simulation data 2
|
|
%====================================%
|
|
%path = '../probes/0.05/p'; % 2.1.x
|
|
path = '../postProcessing/probes/0.05/p'; % 2.2.x
|
|
columns=22;
|
|
headerlines=23;
|
|
data = loaddata(path,columns,headerlines);
|
|
data=transpose(data);
|
|
[x,y]=size(data)
|
|
dp_sim_2 = (data(:,2)-data(:,y))*rhoG; % conversion to Pa
|
|
t_sim_2 = data(:,1);
|
|
%fprintf('final pressureDrop of sim = %f Pa\n',dp_sim(length(dp_sim)) )
|
|
|
|
|
|
%====================================%
|
|
% analytical calculation
|
|
%====================================%
|
|
|
|
%===================
|
|
% Ergun Equation
|
|
%===================
|
|
fprintf('\ncalc Ergun eqn:\n')
|
|
dp = 0.001 % particle diameter
|
|
phip = 1 % sphericity
|
|
epsilon = 0.451335 % void fraction
|
|
Ustart = 0.002
|
|
Uend = 0.02
|
|
timeStepSize = 0.001; % time interval of pressure data
|
|
Tstart = 0;
|
|
Tend = t_sim(length(t_sim))
|
|
Tend=0.1
|
|
deltaU=(Uend-Ustart)/((Tend-Tstart)/timeStepSize);
|
|
U = Ustart+deltaU:deltaU:Uend; % velocity over time
|
|
Ua = U / epsilon; % physical velocity
|
|
L = 0.0156 % length of bed
|
|
nuG = 1.5*10^-4 % kinemat Visk in m2/s
|
|
muG = nuG*rhoG % dynam visc in Pa s
|
|
|
|
dpErgun= L * (
|
|
150*((1-epsilon)^2/epsilon^3)*((muG.*U)/(phip*dp)^2)
|
|
+1.75*((1-epsilon)/epsilon^3)*((rhoG.*U.^2)/(phip*dp))
|
|
);
|
|
|
|
fprintf('NOTE: this pressure is divided by density (according to CFD solver)\n')
|
|
fprintf('so the result does not depend on density\n')
|
|
|
|
%fprintf('final pressure drop (Ergun eqn)= %f Pa\n',dpErgun)
|
|
|
|
%==================================
|
|
% min fluidization velocity in m/s
|
|
%==================================
|
|
rhoP = 2000 % particle density in kg/m3
|
|
g = 9.81 % gravity m/s2
|
|
Umf = dp^2*(rhoP-rhoG)*g/(150*muG)*(epsilon^3*phip^2)/(1-epsilon);
|
|
ReMF = Umf*dp*rhoG/muG;
|
|
if(ReMF<20)
|
|
fprintf('applying eqn1 for Umf.\n')
|
|
elseif(ReMF>20 && ReMF<1000)
|
|
fprintf('applying eqn1 for Umf.\n')
|
|
elseif (ReMF>=1000)
|
|
fprintf('applying eqn2 for Umf.\n')
|
|
Umf = sqrt(dp*(rhoP-rhoG)*g/(1.75*rhoG)*epsilon^3*phip);
|
|
ReMF = Umf*dp*rhoG/muG;
|
|
end
|
|
|
|
dpUmf= L * (
|
|
150*((1-epsilon)^2/epsilon^3)*((muG.*Umf)/(phip*dp)^2)
|
|
+1.75*((1-epsilon)/epsilon^3)*((rhoG.*Umf.^2)/(phip*dp))
|
|
);
|
|
|
|
%====================================%
|
|
% plot data
|
|
%====================================%
|
|
|
|
%figure(2)
|
|
%plot(U,dp_sim)
|
|
%title("Ergun pressure drop vs. simulation")
|
|
%a=strcat("analytical (Ergun), Umf=",num2str(Umf),", dpUmf=",num2str(dpUmf));
|
|
%legend(a,"simulation")
|
|
%xlabel("velocity in [m/s]")
|
|
%ylabel("pressure drop [Pa]")
|
|
%axis([0,Uend,0,dpErgun(length(dpErgun))])
|
|
|
|
figure(1)
|
|
plot(U,dpErgun,U(1:length(t_sim)),dp_sim,U(length(t_sim)+1:length(U)),dp_sim_2,'-+',[Umf,Uend],dpUmf*ones(1,2))
|
|
title("Ergun pressure drop vs. simulation")
|
|
a=strcat("analytical (Ergun), Umf=",num2str(Umf),", dpUmf=",num2str(dpUmf));
|
|
legend(a,"simulation")
|
|
xlabel("velocity in [m/s]")
|
|
ylabel("pressure drop [Pa]")
|
|
axis([0,Uend,0,dpErgun(length(dpErgun))])
|
|
|
|
%print('cfdemSolverPiso_settlingTest.eps','-deps2')
|
|
print -color "cfdemSolverPiso_ErgunTestMPI.eps"
|
|
|