I have made converging and diverging cone by code below. How I can made converging cone then diverging cone then cylider then diverging cone to pass fluid from top to bottom

>> [r,theta]=meshgrid(0:0.1:1, 0:pi/60:2*pi); >> x=r.*cos(theta); >> y=r.*sin(theta); >> z=r; >> mesh(x,y,z); >> hold on >> mesh(-x,-y,-z);