Too many input arguments.

Hi everyone, I tried to generate a figure but got the above. Can someone show me where I could have gone wrong

function f = emu(t, x, nd, alpha, mu, D0, Vol, g, D)

hs = x(1);

D = x(2);

lambda = 1;

% xx = (hd-hw);

% if xx <= 0

% lambda = 0;

% end

theta_0 = nd*pi*D^3 /(6*Vol);

theta_m = nd*pi*(D+L)^3 /(6*Vol);

ftheta_0 = (1 - theta_0)^5.3;

Delta_rho = rho_B - rho_O;

Vst0 = Delta_rho*g*D0^2 /(18*mu);

K1 = abs((2/3)*alpha*Vst0^2 *ftheta_0^2 /(D0 * ((theta_m/theta_0)^(1/3)-1)));

D = sqrt((abs((2/3)*alpha*Vst0*ftheta_0/((theta_m/theta_0)^(1/3)-1)*D0*t +D0^2)));

dhs = lambda*(K1*t + Vst0*ftheta_0);

%dD = lambda*alpha/3 *(Vst0*ftheta_0)/((theta_m/theta_0)^(1/3) - 1) *D0/D;

f = [dhs;dD];

end

Code to generate figure:

clc, clear all, close all

%% Oil/Water System at 30C (Paraffin)

Vol = 900; % Volume for emulsion injected

g = 9810; % mm/s^2 - gravity

L = 0.5e-6; % distance between the surfaces of neighboring bubbles (guessed value)

nd = 1000; % guessed value for no. of bubbles

mu = 3.8; % Viscosity in mPa.s-1

rho_O = 7.97*10^-9; % Oil Density in kg/mm3

rho_B = 9.98*10^-9; % Brine Density in kg/mm3

sigma =21e-3; % Interfacial Tension mN/mm

theta_d = 0.74;

alpha = 0.08;

% Concentration for this system is 200ppm

%mu = 3.8e-3; % Viscosity mPa/s

D0 = 0.3; % converted 300um

H = 225; % in millimeters - initial height

% H = 225e-3;

tspan = [0 180];

hs0 = H;

x0 = [hs0, D0];

[t,x] = ode45(@(t,x)emu(t, x, nd, alpha, mu, sigma, D0, Vol, g, L), tspan, x0);

% plotting graph

figure

plot (t, real(x(:,1)), '-o')

hold on

plot(t, imag(x(:,1)))

hold off

grid on

ylabel ('H(mm)')

xlabel ('Time (s)')

set(gca, 'YScale','log')

title ('Simulation of Sedimentation-Coalesence Experiment')

Command Window Results:

Error using emu

Too many input arguments.

Error in fig>@(t,x)emu(t,x,nd,alpha,mu,sigma,D0,Vol,g,L) (line 30)

[t,x] = ode45(@(t,x)emu(t, x, nd, alpha, mu, sigma, D0, Vol, g, L), tspan, x0);

Error in odearguments (line 92)

f0 = ode(t0,y0,args{:}); % ODE15I sets args{1} to yp0.

Error in ode45 (line 107)

odearguments(odeIsFuncHandle,odeTreatAsMFile, solver_name, ode, tspan, y0, options, varargin);

Error in fig (line 30)

[t,x] = ode45(@(t,x)emu(t, x, nd, alpha, mu, sigma, D0, Vol, g, L), tspan, x0);

Answer 1

[Torsten]

emu has 9 input parameters, but you call it with 10.

9 inputs:            function f = emu(t, x, nd, alpha, mu, D0, Vol, g, D)
10 inputs assumed:   [t,x] = ode45(@(t,x)emu(t, x, nd, alpha, mu, sigma, D0, Vol, g, L), tspan, x0);

[Matthew Charles]

Thanks!