Other PDE heat equation

*To*: mathgroup at smc.vnet.net*Subject*: [mg79679] Other PDE heat equation*From*: Miguel <misvrne at gmail.com>*Date*: Wed, 1 Aug 2007 05:14:30 -0400 (EDT)

How can I to resolve the unidirectional heat transmission for a plate o slab: a=0.03;hc=1890;k=34;L=0.03; NDSolve[{a D[u[x,t],{x,2}]==D[u[x,t],t], u[L,0]==600, (* Initial value: the plate has the same temperature *) u[-L,0]==600, u[0,0]==600, (D[u[x,t],x]/.x->0)==0 (* Max. in centre *) (D[u[x,t],x]/.x->L)==(-hc/k)(u[L,t]-600) (* Q convection = Q conduction *) u[L,t]==u[-L,t]}, (* Temper. symetric *) u[x,t],{x,-L,L},{t,0,10}] NDSolve::ivone: Boundary values may only be specified for one \ independent variable. Initial values may only be specified at one \ value of the other independent variable. >> Where is my error? Thanks