The present work investigates influence of surface parametres on nucleate pool boiling of FC-72 and their impact on critical heat flux development. The stainless steel surface of ribbon heaters was textured using a pulsed nanosecond laser to increase it's roughness and create various surface structures. Analysis of surface topografy was performed using scaning electron microscopy (SEM), optical interferometry and surface wickability measurements. Pool boiling experiments of saturated FC-72 were performed to determine critical heat flux (CHF) values of laser textured surfaces. We achieved enhacement of CHF values up to 75% for all ribbon heaters samples in comparison with non-textured one. Surface roughness parameters were used to analyse surface topography. Furthermore, impact of these parameters on CHF enhancement was investigated. We concluded that combination of several surface roughness parameters in combination with complex surface topography and surface wickability impact on CHF values. Aging of samples proved surface wickability as a sufficient parameter for CHF development of the particular surface. Hsu And Kandlikar's theory of active nucleation sites was confirmed using SEM to determine microcavities.
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