Critical heat flux enhancement by single-layered metal wire mesh with micro and nano-sized pore structures

Abstract

This study reports the results of critical heat flux (CHF) enhancements by using single-layered metal wire mesh with micro/nano-sized pore structures with no modification of the original heating surface. Pool boiling tests with the wire mesh showed a significant CHF increment of up to 84% compared with that recorded on a bare surface. And, we investigated the dynamic behavior of the liquid and vapor phases on the boiling surfaces using an IR thermometry technique. From the quantitative measurements of liquid vapor-solid phase distribution on the heating surface, it was revealed that the presence of the wire mesh and its hydrophilic nature play a role in sustaining a liquid phase inside the heating area that prevents the excessive expansion of the dry spot, and strongly disseminates thermal energy generated by the heater. In other words, the thermal energy generated inside the heater is dispersed more uniformly under the existence of the wire mesh. Using this type of mesh with the micro-sized pore structures for CHF enhancement intrinsically can mitigate changes in thermos-physical and chemical properties, and losses in structural durability for original heating surface. We expect that the meshes can be exploited in applications to several thermal systems. (C) 2017 Elsevier Ltd. All rights reserved.