Pump - Problems

[klausp]

Hi guys,

I am having some problems with a small project.
Nowadays I am studing chemical engeneering and in one subject we are working
with Octave. I am not "that expert".
It´s a simples pump situation. The problem is returning the message
following message:
warning: matrix singular to machine precision, rcond = 0
warning: attempting to find minimum norm solution
warning: dgelsd: rank deficient 3x3 matrix, rank = 2
warning: matrix singular to machine precision, rcond = 0
warning: attempting to find minimum norm solution
warning: dgelsd: rank deficient 3x3 matrix, rank = 2

I can´t find anything wrong on the code:
------------------------------------------------------------------------
%pump1
clear all;

#FUNCTION DEFINITION
function y=fun(x)


#VARIABLES
%x=diam;

P2=x(1)
Q= x(2);
FM=x(3);

#PARAMETERS DEFINITION AND CONVERTION TO INTERNATIONAL SISTEM
P1=14.696;%psi
P3=14.696;%psi
P1=P1*6894.75729;%Pa
P3=P3*6894.75729;%Pa



a=16.7; %psi
a=a*6894.75729;

b=0.052;%psi/(gpm)^1,5
b=6894.75*b;%Pa/(gpm)^1,5
L=50;%ft
L=0.305*L;%m
p=62.4;%lbm/ft3
p=16.02*p;%kg/m3

vis=0.00003228;%VISCOSITY-lbs/ft2
vis=0.00102;%m.s/ft2


E=0.00006;%metros

D=2.469;%in
D=D*0.0254;meters
v=2;%m/s

#Another equations
Re=p*v*D/vis; %Reynolds
Q=(pi*(D/2)^2)*v; %m^3/s



#EQUATIONS SET
y(1)=a-b*Q^1.5-P2+P1; %Empirical/Pump
y(2)=(8*FM*p*L*Q/(pi*D^5))-P2+P3;%Relation flow and pressure loss
y(3)=-2*log10((E/(3.7*D))+(2.51/(Re*sqrt(FM))))-1/sqrt(FM);%Coolebrock
equation


endfunction


#Initial values

x0=[200105 5 1.5e-2];


%Solving

[x,fval,info]=fsolve(@(x) fun(x),x0);

---------------------------------------------------------------------------------------------

I would be thankfull for your help,

Klaus Peter




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