Copenhagen Suborbitals on regenerative cooling and water hammer effect

[Zephram Kerman]

Copenhagen Suborbitals put up a nice vid about how regenerative cooling works, featuring a cross-section of a failed engine. They also talk about laminar flow cooling and water hammer effect.

 

 

[Vanamonde]

As this is talking about actual spacecraft rather than game ones, the thread has been moved to Science & Spaceflight. 

[Starman4308]

Very interesting video! I'll point out that the engineering complexities involved in regenerative cooling are enough that the RS-68, used by the Delta IV rockets, instead uses mechanically simpler ablative cooling, where they basically coat the interior of the rocket nozzle with a heatshield material.

I also suspect regenerative cooling is part of what drives RP-1 being so heavily refined; you really don't want fuel passing over your nozzle to start coking and forming tars and deposits: you need those passages clear. Liquid oxygen isn't exactly a great choice either, on account of being liquid oxygen.

I believe part of why the A-4 rockets produced by Germany in the 1940s used 70% alcohol in water was because that mixture has a cool flame temperature, which reduces stress on the engine.