{"id":300,"date":"2014-03-25T07:00:19","date_gmt":"2014-03-25T07:00:19","guid":{"rendered":"http:\/\/www.waters.to\/blog\/?p=300"},"modified":"2014-03-25T07:00:19","modified_gmt":"2014-03-25T07:00:19","slug":"rocket-nozzles-part-2-the-3d-model","status":"publish","type":"post","link":"http:\/\/www.waters.to\/blog\/rocket-nozzles-part-2-the-3d-model\/","title":{"rendered":"3D Printable Rocket Nozzles Part 2: The 3D Model"},"content":{"rendered":"

In Part 1 of this post<\/a>, I presented the math behind a rocket nozzle.<\/p>\n

Here, in part 2, I’ll show you how I turned that math into a 3d model!<\/p>\n

First, the fun stuff… I posted my code to Thingiverse at http:\/\/www.thingiverse.com\/thing:280483<\/a> where you can play with it live via the Thingiverse customizer.<\/p>\n

How does it work? Well, first, I built an OpenSCAD script, using the math from Part 1 to build a 2D shape like this:<\/p>\n

<\/p>\n

\r\nfull2dNozzle(Rinlet = Rinlet, Ain = Ain, Rthroat = Rthroat,\r\n             Rexit = Rexit, Aout = Aout, pct = pct);\r\n<\/pre>\n
<\/code><\/p>\n
\"2dNozzle\"<\/a><\/p>\n
This shape is actually two half-nozzles, one a conic nozzle and one a parabolic nozzle.  Here, the inlet arc is 1.5 * Throat Radius, and outlet arc is .382 * Throat Radius, as shown in Part 1.<\/p>\n
Once I have defined a function ‘full2dNozzle’ to draw the 2d shape, it is a one-liner in OpenSCAD to twist and extrude it into 3d:<\/p>\n
\"nozzle\"<\/a><\/p>\n
<\/p>\n
\r\nrotate_extrude() rotate([0, 0, -90])\r\n         full2dNozzle(Rinlet = Rinlet, Ain = Ain, Rthroat = Rthroat,\r\n                 Rexit = Rexit, Aout = Aout, pct = pct);\r\n<\/pre>\n
<\/code><\/p>\n","protected":false},"excerpt":{"rendered":"
In Part 1 of this post, I presented the math behind a rocket nozzle. Here, in part 2, I’ll show you how I turned that math into a 3d model! First, the fun stuff… I posted my code to Thingiverse … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-300","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t