Papers by Keyword: Spray Characteristic

Abstract: The increasing effort on the environmental impacts of fossil fuel based power generation has led to increased research with the aim of reducing emissions and improving combustion efficiency by turning to alternative fuel such as biodiesel. But the hazardous emission caused by biodiesel is still a problem that need to tackle. One of way to achieve this is by choosing the correct nozzle characteristic. In the current study, the effect of nozzle angle on mixture formation and combustion characteristic are investigate using air-assisted fuel atomizing biodiesel burner. The nozzle angle that was used are θ = 45⁰ and 50⁰. The results show with nozzle 45⁰ produce lower spray penetration, but higher spray angle and spray area compare to nozzle 50⁰. The result are similar on flame development. For the emission characteristic, the Carbon Monoxide (CO) and Hydro Carbon (HC) emission had a strong reduction by using nozzle with 45⁰ angle compare to 50⁰ angle.

Abstract: The key issue in using vegetable oil-based fuels is oxidation stability, stoichiometric point, bio-fuel composition, antioxidants on the degradation and viscosity thus influences to the different spray atomization and fuel air mixing characteristics. Purpose of this study is to investigate the effect of preheated biodiesel on fuel properties, spray characteristics and mixture formation. The detail behavior of mixture formation was investigated using the direct photography system with a digital color camera. This method can capture spray evaporation, spray length and mixture formation clearly with real images. Increased preheated fuel is found to enhance the spray penetration, resulting in increased the spray area and enhanced fuel-air premixing.

Abstract: In Minimum Quantity Lubrication machining, cutting fluid is provided as mist. Mist with different velocity and diameter may lead to different cooling, lubrication effect and cutting quality. Thus, cutting quality is highly influenced by spray characteristics in MQL machining. In this study, the mathematics model of mist flow was set up first. Then spray characteristics were tested by a 3-Dimensional Particle Dynamic Analyzer. In order to study the influence of spray characteristics on cutting quality, precision turning of 45 steel was performed by a CNC Super Precision Machine Tool. The results indicate that the lowest surface roughness was obtained by supplying more cutting fluid at proper position for spraying distance of 20mm.