CTRC Breakthroughs
Surface and Interface Engineering
Research Topics
Microscale Transport and Microchannels
Electrically Actuated Microscale Flows
Thin-Film Transport, Wicks and Heat Pipes
Novel Air and Impingement Cooling Approaches
Surface and Interface Engineering
Thermal Materials R&D
Thermal Interfaces
Small-Scale Refrigeration
Exploratory and Novel Concepts
Renewable and Sustainable Energy
Surface Treatment for Boiling Heat Transfer Enhancement
The present study proposes a free particle technique to provide the
same active nucleation sites as for sintered particles, but with a
deformable particle layer to reduce the vapor pressure drop during
boiling (increases performance). A pool boiling test facility was
constructed to allow high-speed visualization of boiling from a bed
of free particles. Three free particle sizes were tested to
investigate boiling characteristics and heat transfer enhancement
over polished surface. The image shows the passive deformation of
the free particle layer to release vapor bubble during pool boiling.
A 32% reduction in surface superheat up to the same critical heat
flux as measured for the polished surface is measured.
Acoustically Enhanced Heat Transfer
The aim of the project is the enhancement of heat transfer with an
acoustic sound field with, ideally, a smaller pressure drop in
comparison to other surface enhancements. This project involved
experimental investigation of acoustically enhancing the heat
transfer from a fluid flow to the solid wall of a plain tube and
determining the influence of an acoustic field on the rate of heat
transfer. A prototype test stand had been constructed in which air
was the working fluid. The figure plots dimensionless heat transfer
enhancement (Q/Q0) against
the frequency at various sound levels (top) showing that heat
transfer can be enhanced with an acoustic field by up to 30%.
Differential pressure inside of the test section plotted against the
frequency (below) shows that with a particular frequency, the
differential pressure is negative.
