sf[i_,j_]:=Min[1,(((i/wwu))^2)+(((j/wwv))^2)]

tf[t_]:=Sin[π t/p]

u[i_]:=ua Sin[i/wu π/2.]

v[i_]:=va Sin[i/wv π/2.]

s[i_,j_,t_]:=tf[t](u[i]+v[j])(1+Cos[π sf[i,j]])/2

p=10; wwu=100; wwv=70; ua=1; va=1; wu=100; wv=70; DynamicModule[{t=0},{Manipulator[Dynamic[t],{0,100}],Dynamic[Plot3D[Sin[π t/p](u[i]+v[j])(1+Cos[π sf[i,j]])/2,{i,-100,100},{j,-100,100},PlotRange->{{-100,100},{-100,100},{-1,1}}]]}]