Performance degradation of Sintered wick copper-water Heat Pipes (SHP) due to bending

Industrial applications frequently require bending of heat pipes, which was historically recognised as a mechanism for thermal performance degradation. The purpose of this research is to characterise the performance of sintered copper-water heat pipes for aerospace applications, with bend radii ≤3 x heat pipe diameter, as a function of bend angle.
An experimental study has been conducted and compared against predicted performance from Boyd's proprietary analytical heat pipe calculation. The study evaluates the thermal resistance (Rth) and maximum heat transfer capacity (Q max ) of heat pipes over incremental bend angles (0 ◦ , 45 ◦ , 90 ◦ , 135 ◦ , 180 ◦ ). All heat pipe thermal testing was conducted at horizontal orientation to reproduce space conditions (zero gravity). The results showed that for space use (or terrestrial use at ϕ = 0 ◦ ), i) No consistent evidence that introducing a
single bend to Sintered Copper-Water Heat Pipe (SHP) degrades its thermal performance, ii) No conclusive correlations between SHP bending and thermal performance degradation has been observed from this research.