OK, well now what you're describing is a thermosyphon (also called gravity loop heat pipe). Just like a wick heat pipe, except no wick so they must be oriented ad you have shown so that gravity can return the condensed liquid to the evaoprator. They work just fine, comparable to other heat pipes depending on working fluid and construction of the heat exchange surfaces. Water is a terrible working fluid... Refrigerants are normally used, in particular acetone.
post #11 of 15
4/1/12 at 2:22am