الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
Enhanced pool boiling heat transfer has been and still being the
focus of attention of thermodynamics engineering that draws the interest
of numerous researchers. Although. single-phase heat transfer provides
only a marginal opportunity for improvement above and beyond the
addition of extended surface area, some enhanced boiling surfaces
produce up to 100 times the performance of a conventional plain surface
under certain conditions. Most of the work was concentrating on the
study of conventional heating surfaces in boiling heat transfer. This does
not represent the real life case of heating sections in heat pipes.
In the present work, the boiling heat transfer coefficient IS
investigated experimentally by means of a built-up apparatus on a smooth
isothermal heating surface covered by fixed thickness porous wick
material prepared by hardening of well mixed mixture of Aluminum
powder and Cement powder with different percentages by weight. The
physical properties (porosity, permeability, capillary pressure, density and
thermal conductivity) of the sintered wick material were determined by
means of a built-up apparatus for the purpose of measuring these
properties.
The experiments were conducted at atmospheric pressure for
distilled water, acetone and hexane as boiling fluids. The isothermal
heating surface is obtained by using the condenser surface of a copper flat plate thermo-siphon heat pipe.
The results show that the combined wicking material covering a
plain surface enhances the boiling heat transfer in some range of the heat
fluxes under investigation for the working fluids considered in this thesis.