Due to the complexity of spray combustion, detailed investigation requires the decoupling of the gas and liquid phase to characterise the swirling flow and understand the transport of the droplets. The PIV diagnostic is applied to measure the gas phase flow field under reacting and non-reacting flow. The liquid phase of droplets is characterised using the phase Doppler anemometry (PDA) for droplets velocity and size in flames established using biodiesels or baseline fuels. Single swirl flame burner is designed with the capability to produce power output of 5-8 kW, which corresponds to the fuel mass fuel flow rate of 0.1-0.2 g/s for diesel and Jet-A1, respectively. For PIV measurements, the total bulk flow of air is split into two lines, of which ∼90% of air is supplied through the heater for preheating, while ∼10% of air is used for PIV seeding. Results show that visible spray region of Jet-A1 spray is significantly smaller at elevated temperature of 200 °C compared to the heavier fuel of diesel where the temperature of 200 °C is not sufficient to completely vaporise the droplets of the spray.
