MATLAB: How to solve this bvp4c

boundary value problembvp4chelpmathematicsMATLAB

Hello, can anyone help me solve this bvp4c program?
as to solve this problem, I already try numerous initial numbers.
it's either 
Unable to solve the collocation equations -- a singular Jacobian encountered.
or
Warning: Unable to meet the tolerance without using more than 1250 mesh points.
 The last mesh of 892 points and the solution are available in the output argument.
 The maximum residual is 85.3834, while requested accuracy is 1e-07.
here is the bvp4c:
format long g
global alpha beta phi phid epsilon delta rhoS rhoF Y betaT Ec cpS cpF kf knf Pr Tv A B w Q ks
a=0; b=15;
phi=0.5;phid=0.2;delta=0.5;A=0.5;B=0.5;w=1.5;
betaT=0.2;alpha=0.5;beta=0.5;Ec=0.2;Y=0.01;Pr=6.2;Tv=0.488;epsilon=0.1; 
rhoF=997.1;cpF=4179;kf=0.613;   
rhoS=8933;cpS=385;knf=0.81629325;  
Q=((ks+(2*kf))-(2*phi*(kf-ks)))/((ks+(2*kf))+(phi*(kf-ks))); ks=400;
solinit = bvpinit(linspace(a,b,100),@fluidparticle_init);
options = bvpset('stat','on','RelTol',1e-7); 
sol = bvp4c(@fluidparticle_ode,@fluidparticle_bc,solinit,options);
sol.y(3,1)      
sol.y(7,1)      
plot(sol.x,sol.y(2,:),':r')    
function dydx=fluidparticle_ode(x,y,alpha,beta,phi,phid,Y,betaT,Ec,kf,knf,Pr,Tv,A,B,rhoS,rhoF,cpS,cpF,Q)
global alpha beta phi phid Y betaT Ec kf knf Pr Tv A B rhoS rhoF cpS cpF Q
dydx=[y(2);
      y(3);
      (((1-phi)^2.5)*(1-phi+(phi*(rhoS/rhoF)))*((y(2)^2)-(y(1)*y(3))))-((((1-phi)^2.5)/(1-phid))*alpha*beta*(y(5)-y(2)));
      y(5);
      ((y(5)^2)-(beta*(y(5)-y(2))))/y(4);
      y(7);
        (1-phi+(phi*((rhoS*cpS)/(rhoF*cpF))))*(Pr/Q)*((2*y(2)*y(6))-(y(1)*y(7)))-((Pr/Q)*((alpha*betaT*(y(8)-y(6)))-((alpha*Ec/Tv)*((y(5)-y(2))^2))))
      ((2*y(5)*y(8))+(Y*betaT*(y(8)-y(6))))/y(4)];
function res=fluidparticle_bc(ya,yb,epsilon,delta,w)
global epsilon delta w
res=[ya(2)-epsilon-(delta*ya(3))
    ya(1)
    yb(2)
    yb(5)
    yb(4)-yb(1)
    ya(6)-1-(w*ya(7))
    yb(6)
    yb(8)];
function v=fluidparticle_init(x)
v=[0.5
   -exp(-x) 
  exp(-x)
   0.3
  -0.5
   -exp(-x)
   exp(-x)
   -exp(-x)];
what should I adjust in this program?
thank you in advance for your help and kindness.

Best Answer

I re-wrote the main equations (compare yours and mine) and tried b = 1
Check the attachment
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