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In this paper, experimental investigation on spray atomization and droplet dynamics inside a thermostatic expansion valve (TXV), a component commonly used in vehicle refrigeration system, was conducted. A needle and an orifice were copied from a commercial TXV and machined to be mounted inside a chamber with optical access so that the flow inside the TXV is simulated and visualized at the same time. The break-up and atomization of the refrigerant were documented near the downstream of the orifice under different feed conditions for two TXV with different geometry. A Phase Doppler Anemometry (PDA) system was used later to measure the size and velocity of atomized refrigerant droplets. The results showed that the droplet size variation along the radial direction is slightly decreased at near downstream and increased at farther downstream due to the coalescence.

This paper focuses on the spray and atomization characteristics of a Micro-Variable Circular-Orifice (MVCO) fuel injector coupled with a unique swirl adapter. Spray characteristics produced from this configuration, such as spray penetration length, spray velocity and the droplet size distribution were evaluated under different injection pressure and air inlet pressure. Diesel injection pressure ranges from 300 bar to 700 bar at a back pressure of 1bar while compressed air at pressures of 2 bar and 4 bar was supplied to the swirl adapter. High speed Mie scattering images were recorded to capture the spray evolution, as seen from both the front view and the bottom view. Phase Doppler Anemometry (PDA) measurements were conducted at different locations in the spray for the acquisition of droplet sizes and velocity distributions.

The purpose of this study is to investigate the possibility of acetone-butanol-ethanol (ABE) blended with diesel without further component recovery which has high costs blocking the industrial-scale production of bio-butanol. The combustion characteristics of ABE and diesel blends were studied in a constant volume chamber. In this study, 50% and 80% vol. ABE (without water) were mixed with diesel and the vol. % of acetone, butanol and ethanol were kept at 30%, 60% and 10% respectively. The in-cylinder pressure was recorded using a pressure transducer and the time-resolved natural luminosity was captured by high speed imaging. Combustion visualization using laser diagnostics would provide crucial fundamental information of the fuel's combustion characteristics. With the different percentage of the ABE blended in the diesel, the soot oxidation, the ignition delay and the soot lift-off length were studied in this work.