Experiment study of Droplet Evaporation Boiling Curve using Aluminium

Abstract

This experiment is about study of the water droplet evaporation boiling curve using aluminium. Boiling is the most familiar form of heat transfer. Boiling takes different forms, depending on the value of the temperature. There are four different boiling regimes was observed that is natural convection boiling, nucleate boiling, transition boiling, and film boiling. The problem statement in this experimental study is to develop droplet evaporation boiling curve using aluminium. This curve could be obtained by carried out a heat transfer experiment by using aluminium without any coating. Then, based on the graph, there are two important points need to be highlight which is Critical Heat Flux (CHF) and Leidenfrost point (LFP). Besides that, the next problem statement is to identify the droplet behaviour on the heated surface. The formation of the droplet would change stage by stage as the temperature increased. The droplet behaviour is the main factor that affected the droplet evaporation times. This two points can be regarded as an important study in boiling heat transfer research. The objective of this experiment is to study the droplet evaporation boiling curve using aluminium specimen and also to obtain The Critical Heat Flux (CHF) point and Leidenfrost Point (LFP) base on the graph of boiling curve from the result. Methodology in this project consists of cutting the material, grinding and polishing then the experimental work was conducted followed by planning. As a result, it can be concluded that the Critical Heat Flux are achieved at a surface temperature approximately between 130oC to 140oC and the Leidenfrost Point approximately at a surface temperature between 160oC to 170oC. Besides, the droplet behaviour are shown in nucleate boiling, transition boiling, and film boiling regime.