Experimental study on the heat transfer performance of ultra-thin flattened heat pipe with hybrid spiral woven mesh wick structure

•An ultra-thin flattened heat pipe with hybrid spiral woven mesh wick is designed.•The wick is hybrid woven from different-diameter copper wires in every strands.•Effect of the number and distribution of the wires on the performance is studied.•The optimum design of weaving wick structure for high heat transfer is provided.