Detailed analysis of nucleating surface temperatures using thermochromatic liquid crystal technique and temporal-temperature response under various heat flux and at 813.6kPa (118Psia) and 882.5kPa (128Psia) in R134A refrigerant has been performed. Liquid crystals thermo-chromatography uses encapsulated liquid crystals that are sensitive to temperature. The visualization system uses two high resolution and fast shutter speed cameras: one to measure the temperature and another to capture the bubble dynamics. Bubble frequency is found to be linearly proportional to the heat flux between 2500W/m2 and 5000W/m2. Bubble growth and departure have been captured. As the bubble departs from the surface, it is replaced by cooler fluid. This transient effect or form of micro-convection occurs at the same rate as the bubble frequency. Results show that this phenomenon occurs in less than 2ms and experiences a temperature drop of 2.5°C. From the time of departure, the temperature slowly rises roughly 1°C until the birth of the next bubble.

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