%0 Journal Article
	%A R. Hosseini and  A. Gholaminejad and  H. Jahandar
	%D 2011
	%J International Journal of Aerospace and Mechanical Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 55, 2011
	%T Roughness Effects on Nucleate Pool Boiling of R-113 on Horizontal Circular Copper Surfaces
	%U https://publications.waset.org/pdf/11858
	%V 55
	%X The present paper is an experimental investigation of
roughness effects on nucleate pool boiling of refrigerant R113 on
horizontal circular copper surfaces. The copper samples were treated
by different sand paper grit sizes to achieve different surface
roughness. The average surface roughness of the four samples was
0.901, 0.735, 0.65, and 0.09, respectively. The experiments were
performed in the heat flux range of 8 to 200kW/m2. The heat transfer
coefficient was calculated by measuring wall superheat of the
samples and the input heat flux. The results show significant
improvement of heat transfer coefficient as the surface roughness is
increased. It is found that the heat transfer coefficient of the sample
with Ra=0.901 is 3.4, 10.5, and 38.5% higher in comparison with
surfaces with Ra of 0.735, 0.65, and 0.09 at heat flux of 170 kW/m2.
Moreover, the results are compared with literature data and the well
known Cooper correlation.
	%P 1421 - 1426