//simple conical DeLaval nozzle by buback //Great Info here: http://www.braeunig.us/space/propuls.htm //Radii Dr = 20; //Divergent nozzle exit radius t = 5; //throat radius Cr = 20; //combution chamber radius //Angles Da = 15; //divergent section angle. typ 12-18 deg Ca = 40; //Convergent section angle. typ 20-45 deg Ld = (Dr-t)*(sin(90)/sin (Da)); //Divergent section length, as determined by Da Lc = (Cr-t)*(sin(90)/sin(Ca)); //Convergent section length, as determined by Ca translate([0,0,-Ld/2]){ cylinder(h = Ld, r1 = Dr, r2 = t , $fn=80,center=true); } translate([0,0,Lc/2]){ cylinder(h=Lc, r1 = t, r2 = Cr, $fn=80,center=true); }