Investigation of bubble dynamics in nucleate boiling

• Grant number: 23/12381-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: October 01, 2023
• End date: July 31, 2025
• Field of knowledge: Engineering - Mechanical Engineering - Transport Phenomena
• Principal Investigator: Debora Carneiro Moreira
• Grantee: Gabriel Santinello Chahad
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil
• Associated research grant: 22/06392-7 - Experimental study and modelling of nucleate boiling heat transfer intensification through surface texturing, AP.GR

Abstract

Nucleate boiling is essentially influenced by interfacial mechanisms, and the global heat transfer performance of heat exchangers based on nucleate boiling is directly related to the characteristics of vapor bubbles that nucleate and grow on the heated surface, as well as its detachment behavior. This work is focused on studying the characteristics of vapor bubbles nucleating from singular artificial cavities. The effects of operational conditions of the boiling chamber in bubble nucleation, growth and detachment characteristics will be analyzed and further explored with regards to distinct characteristics of surrounding surfaces. The topography of cavities and the surrounding surface characteristics will be analyzed through confocal microscopy and static and dynamic contact angles measurements. The heat transfer performances of the samples will be compared to that of plain surfaces with similar characteristics to the surfaces surrounding the cavities, and related to the observed bubble dynamics. An algorithm in Matlab to measure and track bubbles based on high-speed images and automatically assess bubble departure frequency, detachment diameter and velocities will be developed.