Turbulent Inhomogeneous Autoignition of Liquid Fuels
Motivated by recent experimental and computational findings for gaseous fuels, we design and develop a state-of-the-art experimental apparatus for a parametric study of the effect of flow inlet conditions on autoignition of polydispersed droplets of pure liquid fuels. A vertically mounted and optically accessible quartz reactor of circular cross-section receives upwards flowing air with temperatures up to 1150 K and velocities up to 40 m/s. Liquid fuel is injected continuously and axisymmetrically from a water-cooled circular nozzle (placed concentrically at the reactor inlet) into this confined turbulent coflow of high temperature air at atmospheric pressures. We take dynamic measurements of temperature with fine thermocouples and; optical non-intrusive measurements (with high-speed cameras) to obtain quantitative data on autoignition delay time, location, frequency; fuel jet break-up, drop formation and evaporation.
Research application/scope: Improve design of combustors in engines and gas turbines for efficient fuel utilisation and reduction of harmful emissions by predicting and controlling autoignition; validating/developing computational models.
Thermal storage system based on phase change material (PCM)
Studied experimentally the dynamic behaviour and heat transfer performance of a domestic thermal storage system, based on the use of PCMs.
Heat powered two-phase thermofluidic oscillator
Worked on the development of a novel thermally powered fluid pump based on a two-phase thermofluidic oscillator (a fluid system within which oscillations are driven by heat flows as a consequence of heat transfer alone).
• Developed an experimental apparatus for studying the stalling pressure and throughput of the fluid pump as a function of the input temperature difference and geometry.
Rheology and Flow of Non-Newtonian Fluids
Studying numerically and experimentally the start-up flow of non-Newtonian lubricating greases in long pipelines
• Developing a simulation tool for prediction of start-up flow parameters for a grease transfer system
• Focus on determination of the scale-up relations for pressure drop, shear stress, flow rate, and surface heating
• Validation of the numerical predictions through laboratory-scale and plant-scale experiments