In this experimental study, the effects of slope changes on the heat transfer coefficient
in pool boiling in deionized water have been investigated. The experiments were carried out in the average
surface roughness of 0.21 µm on a copper cylinder by changing the surface slope including 0°, 5°,
10°, 15°, 20°, 25°, and 30°. The range of heat flux was from 21 to 77 kW/m in atmospheric conditions.
The results indicated that by increasing the heater slope, the departure frequency and bubble
departure diameter on the heater surface were increased which lead to an increase in the mixing,
turbulence, and heat transfer coefficient. Finally, the slope of 15° has reached the highest heat
transfer coefficient with an increase of 20.09% compared to other slopes. Besides the optimized model
was mostly overlapped with the experimental results in which Stephan Abdelsalam's model with
an average error of 13.9% and the McNelly model with an average error of 24% had the minimum
and maximum amount of error among the other models, respectively.