A droplet vaporization model has been developed for use in high pressure spray modeling. The model is a modification of the common Spalding vaporization model that accounts for the effects of high pressure on phase equilibrium, transport properties, and surface tension. The new model allows for a nonuniform temperature within the liquid by using a simple 2-zone model for the droplet. The effect...

 Flash Boiling atomization is one of the most effective means of generating a fine and narrow-dispersed spray. Unless its complexity its potential has not been fully realized. In This Paper, a three dimensional chamber has been modeled with a straight fuel injector. Effect of Flash Boiling has been investigated by computational fluid dynamics (CFD) techniques. A finite volume approach with the ...

Spray ignition and flame stabilisation in the frame of diesel-like combustion conditions combine fundamental and complex physical and chemical processes. In this work, a numerical investigation has been performed to evaluate the potential of integrating detailed chemistry into CFD calculations, in order to improve predictions and gain more insight in involved processes. This work has been carri...

The influence of additives inducing viscoelasticity in diesel fuel, on the in-nozzle cavitation evolution and expelled spray morphology has been quantified by high-speed, diffused back-light schlieren imaging applied to two single-hole true-scale transparent injectors straight tapered orifice layouts (so-called Spray C D engine Combustion Network), as well a five-hole configuration (Spray M). M...

With the ever rising need for better fuel efficiency and lower emissions, the development of better engine technology is essential. Different strategies are being considered to increase engine efficiency, such as direct injection or downsizing. Certain regimes are clearly identified as optimal for certain range of loads. For gasoline engines, the Homogeneous Charge Compression Ignition (HCCI) c...

In a recent numerical paper (Nicoli et al. Combust. Sci. Technol. vol. 186, pp. 103-119; 2014) [1], a model of isobaric flame propagation in lean sprays has been proposed. The initial state of the monodisperse mists was schematized by a system of individual alkane droplets initially located at the nodes of a facecentered 2D-lattice, surrounded by a saturated mixture of alkane and air. In the pr...

a newly developed heavy duty diesel engine in dual fuel mode of operation has been studied in detail. the main fuel would be natural gas and diesel oil as pilot injection. the importance and effects of mixture preparation and formation through ports, valves and in cylinder flow field with different swirl ratio and tumble on diesel combustion phenomena is an accepted feature which has been studi...

This paper describes a comparative evaluation of two fuzzy-derived techniques for modelling fuel spray penetration in the cylinders of a diesel internal combustion engine. The first model is implemented using conventional fuzzy-based paradigm, where human expertise and operator knowledge were used to select the parameters for the system. The second model used an adaptive neuro-fuzzy inference s...

Modern gas turbine hot sections need to be protected from elevated temperature and damaging environments. This protection starts as a typically two layer coating system, the base layer or bond coat (BC) acts as a corrosion barrier and a kind of buffer for the thermal mismatch between the base material and the second top thermally protective layer or Thermal Barrier Coating (TBC). The BC is norm...

It is well known that the high velocity oxy-fuel based thermal spray process impart high density and reduced porosity in coatings compared to those produced by other ambient thermal spray processes. The benefits of HVOF have largely remained in the domain of metals and cermets and limited investigations have been carried out in ceramic coatings. The ability to produce high density ceramic coati...