Abstract
Experimental investigations into pool boiling heat transfer on finned arrays with internal tunnels limited by copper wire mesh were conducted. The experiments were carried out for water, ethanol and fluorinert FC-72 at atmospheric pressure. The wire net with mesh aperture of 0.3 and 0.5 mm, sintered with the vertical side of the 10 mm high rectangular fins and horizontal inter-fin surface formed a system of connected tunnels. Tunnel width was 0.6 and 1.0 mm. Substantial enhancement of heat transfer coefficient was observed for the investigated surfaces. In water, ethanol and FC-72 boiling the highest increase in the heat transfer coefficient was obtained for the surface with mesh aperture of 0.5 mm and tunnel width of 0.6 mm. The ratio of boiling heat transfer coefficients for the investigated fins with mesh covering and smooth fins (10 mm height), at the heat flux 100 kW/m 2 , was about 3 for water and ethanol as working fluids. NOMENCLATURE a - mesh aperture (opening size), mm h - height (depth), mm, N,NTS - narrow tunnel structure, p - pitch, mm, q - heat flux, kW/m 2 , s - width of space between fins, mm, w - width, mm,
Highlights
The paper deals with experimental investigations of boiling heat transfer on structured surfaces in the form of three main fins with parallel narrow tunnels, covered with copper
An essential heat transfer coefficient increase was observed for porous structures with 3 – 7 layers of nets made of wire with 0.25 – 0.4 mm diameter and mesh aperture of 2 mm
Experimental results indicated that the heat transfer coefficients from surfaces with mesh aperture of 0.0685 mm and 0.0913 mm were much higher than from a surface with aperture of 0.145 mm Pastuszko [3] presented complex experimental investigations of boiling heat transfer on structured surfaces covered with perforated foil
Summary
The paper deals with experimental investigations of boiling heat transfer on structured surfaces in the form of three main fins with parallel narrow tunnels, covered with copper. Experimental investigations of pool boiling heat transfer on micro-fin arrays covered with porous structure were conducted by Pastuszko [4]. The objective of this article is to determine the most advantageous geometry of new enhanced structures with narrow tunnels with respect to boiling heat transfer coefficient intensification, taking into account heat fluxes in the range of 10 – 300 kW/m2
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call