Metal Mesh Structured Heat Pipes are designed in such a way that the wick is placed in the form of metal mesh that is inserted into the pipe and made to be in contact with the inner walls of the pipe to facilitate capillary action. These Heat Pipes are capable of operating in gravity-aided and horizontal orientations and can return the working fluid against gravity at angles of up to 5 Degree from horizontal pattern. These Heat Pipes are designed with a metal felt based wick structure which is held in support by a metal foam. Metal Mesh Structured Heat Pipes can also be used in applications with radial heat fluxes up to 40 W/cm².