function [UserVar,ub,vb,ud,vd]=DefineStartVelValues(UserVar,CtrlVar,MUA,BCs,ub,vb,ud,vd,time,s,b,h,S,B,rho,rhow,GF,AGlen,n,C,m)
Define start values for velocities
[UserVar,ub,vb,ud,vd]=DefineStartVelValues(UserVar,CtrlVar,MUA,BCs,ub,vb,ud,vd,time,s,b,h,S,B,rho,rhow,GF,AGlen,n,C,m)
This user m-file defines the starting values for the velocities. This is just the inital estimate of the solution and, provided the solver converges, it has no impact on the final solution. On the other hand, if a good inital estimate is available, then precribing it may speed up the solution. In most cases a good intial estimate is simply to set all velocities to zero and this is the default approach. So generally this m-file is not required to obtain a solution, but it may speed things up.
end