Intensification of heat transfer during pool boiling of nitrogen on surfaces with capillary-porous coatings produced by 3D-printing

D V Kuznetsov,A N Pavlenko

doi:10.1088/1742-6596/2039/1/012013

Abstract

The study of heat transfer, critical heat fluxes (CHF) and evaporation dynamics at pool boiling of nitrogen at atmospheric and low pressures in a stationary heat generation regimes was performed. The two flat cooper heaters with porous coatings of various structural parameters obtained by additive 3D-printing as well as smooth one were used as working surfaces. According to obtained results such coatings significantly effect on pool boiling increasing up to six times the heat transfer coefficients (HTC) in comparison with uncoated sample. For all investigated heaters and pressures, visualization of boiling was performed using a video camera from which data on the bubble departure diameters and estimates of the active nucleation site density were obtained.

Highlights

As known, phase changes, including boiling, found their application in industry: in the nuclear power, in the chemical industry, in heat power engineering, at cooling of different electronic devices etc
The increasing of heat fluxes which must be removed from energy-intensive surfaces including by reducing the weight and size parameters of equipment stimulate the development of research in the field of heat transfer intensification and increasing the critical heat fluxes at pool boiling of various fluids
The arrows on the figure indicate the critical heat fluxes for all heaters, which were determined by a sharp increase in temperature with an increase in the heat load and from the visualization of the boiling process

Summary

Introduction

Phase changes, including boiling, found their application in industry: in the nuclear power, in the chemical industry, in heat power engineering, at cooling of different electronic devices etc. The amount of research associated with the influence of individual microstructural parameters of the surfaces with different geometry and material, obtained by the SLM method, on HTC and CHF at nucleate boiling of fluids with different properties and variation of experimental

Results

Conclusion