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Question: Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

Question:Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

Madhukesh J K 140 Maple 17
ode syntax 2dmath dsolve numeric differential-equations bvp boundary-conditions
November 25 2020
1


When i try to solve the problem i got error like this 

Please help me get the solution

> 

restart
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with(plots):
> 

eq1 := (2*(eta*(diff(f(eta), `$`(eta, 3)))+diff(f(eta), `$`(eta, 2))))/((1-phi[1])^2.5*(1-phi[2])^2.5)+((1-phi[2])*(1-phi[1]+phi[1]*rho[s1]/rho[f])+phi[2]*rho[s2]/rho[f])*f(eta)*(diff(f(eta), `$`(eta, 2)))-sigma[hnf]*M*(diff(f(eta), eta))/(sigma[f]*(m^2+1)) = 0;

2*(eta*(diff(diff(diff(f(eta), eta), eta), eta))+diff(diff(f(eta), eta), eta))/((1-phi[1])^2.5*(1-phi[2])^2.5)+((1-phi[2])*(1-phi[1]+phi[1]*rho[s1]/rho[f])+phi[2]*rho[s2]/rho[f])*f(eta)*(diff(diff(f(eta), eta), eta))-sigma[hnf]*M*(diff(f(eta), eta))/(sigma[f]*(m^2+1)) = 0

 (1)
> 

eq2 := k[hnf]*(eta*(diff(theta(eta), `$`(eta, 2)))+diff(theta(eta), eta))/k[f]+(1/2)*Pr*((1-phi[2])*(1-phi[1]+phi[1]*`ρC`[p][s1]/`ρC`[p][f])+phi[2]*`ρC`[p][s2]/`ρC`[p][f])*f(eta)*(diff(theta(eta), eta)) = 0;

k[hnf]*(eta*(diff(diff(theta(eta), eta), eta))+diff(theta(eta), eta))/k[f]+(1/2)*Pr*((1-phi[2])*(1-phi[1]+phi[1]*`ρC`[p][s1]/`ρC`[p][f])+phi[2]*`ρC`[p][s2]/`ρC`[p][f])*f(eta)*(diff(theta(eta), eta)) = 0

 (2)
> 

eq3 := 2*(1-phi[1])^2.5*(1-phi[2])^2.5*(eta*(diff(chi(eta), `$`(eta, 2)))+diff(chi(eta), eta))+Sc*f(eta)*(diff(chi(eta), eta))-beta*Sc*(1+delta*theta(eta))^n*exp^(-E/(1+delta*theta(eta)))*chi(eta) = 0;

2*(1-phi[1])^2.5*(1-phi[2])^2.5*(eta*(diff(diff(chi(eta), eta), eta))+diff(chi(eta), eta))+Sc*f(eta)*(diff(chi(eta), eta))-beta*Sc*(1+delta*theta(eta))^n*exp^(-E/(1+delta*theta(eta)))*chi(eta) = 0

 (3)
> 

bcs := f(c) = (1/2)*lambda*c, (D(f))(c) = (1/2)*lambda, theta(c) = 1, chi(c) = 1, (D(f))(10) = (1-lambda)*(1/2), theta(10) = 0, chi(10) = 0;

f(c) = (1/2)*lambda*c, (D(f))(c) = (1/2)*lambda, theta(c) = 1, chi(c) = 1, (D(f))(10) = 1/2-(1/2)*lambda, theta(10) = 0, chi(10) = 0

 (4)
> 

params := {E = .5, M = .1, Pr = 6.2, Sc = .5, beta = .5, c = .1, delta = .5, lambda = -1, m = .5, n = .1, k[f] = .6130, k[hnf] = 1.039626683, phi[1] = .1, phi[2] = .1, rho[f] = 997.1, rho[s1] = 5180, rho[s2] = 1800, sigma[f] = 0.5e-1, sigma[hnf] = 0.8888888337e-1, `ρC`[p][f] = 4.1668809*10^6, `ρC`[p][s1] = 3470600, `ρC`[p][s2] = 1290600};

{E = .5, M = .1, Pr = 6.2, Sc = .5, beta = .5, c = .1, delta = .5, lambda = -1, m = .5, n = .1, k[f] = .6130, k[hnf] = 1.039626683, phi[1] = .1, phi[2] = .1, rho[f] = 997.1, rho[s1] = 5180, rho[s2] = 1800, sigma[f] = 0.5e-1, sigma[hnf] = 0.8888888337e-1, `ρC`[p][f] = 4166880.900, `ρC`[p][s1] = 3470600, `ρC`[p][s2] = 1290600}

 (5)
> 

ODEs := [eq1, eq2, eq3]

[2*(eta*(diff(diff(diff(f(eta), eta), eta), eta))+diff(diff(f(eta), eta), eta))/((1-phi[1])^2.5*(1-phi[2])^2.5)+((1-phi[2])*(1-phi[1]+phi[1]*rho[s1]/rho[f])+phi[2]*rho[s2]/rho[f])*f(eta)*(diff(diff(f(eta), eta), eta))-sigma[hnf]*M*(diff(f(eta), eta))/(sigma[f]*(m^2+1)) = 0, k[hnf]*(eta*(diff(diff(theta(eta), eta), eta))+diff(theta(eta), eta))/k[f]+(1/2)*Pr*((1-phi[2])*(1-phi[1]+phi[1]*`ρC`[p][s1]/`ρC`[p][f])+phi[2]*`ρC`[p][s2]/`ρC`[p][f])*f(eta)*(diff(theta(eta), eta)) = 0, 2*(1-phi[1])^2.5*(1-phi[2])^2.5*(eta*(diff(diff(chi(eta), eta), eta))+diff(chi(eta), eta))+Sc*f(eta)*(diff(chi(eta), eta))-beta*Sc*(1+delta*theta(eta))^n*exp^(-E/(1+delta*theta(eta)))*chi(eta) = 0]

 (6)
> 

``
> 

sol := dsolve(eval([ODES, bcs], params), numeric, output = listprocedure)

Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

  
> 

``


 

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