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A relative velocity correction model (RVC), combined with the drop tracing system and spherical coordinate transformation, was developed and implemented in KIVA-3V code to yield grid-independent results for the spray simulations, especially for 3-D cases. The model applies the theory of steady turbulent jet flow to obtain sectional distribution of the gas-phase velocity along the spray axial in near region, which is used to correct the relative velocity between the drop and gas phases. The computed results were compared with the experimental data for both single-hole and three-hole fuel injections, including the spray tip penetrations and the spray images. The comparison shows that the RVC model performed well for all the cases.

An experimental study has been conducted at small kerosene droplet behavior near well-defined butane diffusion flame for the critical need on high efficient and cleaner energy technology. High temperature of background gas was generated using butane flame. Microflame from butane can reach the maximum temperature around 1200K at tip of outer glass. Single droplet of kerosene was injected by a small injector tube (30 μm-diameter) in to hot environment. Droplet of kerosene was released by attachment of piezo actuator on wall injector. Once the droplet is exposed to the hot atmosphere of micro flame, the temporal regression of the droplet surface was recorded. Droplet diameter was observed by CCD camera with strobe light flash at 180ns. The images captured in this experiment were analyzed by post-processing software to determine the vaporization of droplet.

Small wood biomass gasifier was developed and co-generation system supplying electric power and heat with small spark ignition internal combustion engine (SI-ICE) was investigated. The balance of electric power and heat flux will be controlled with ignition timing and the exhaust gas components were discussed. The wood biomass gasifier (downdraft type) had 105mm in inner diameter and 1000mm in length and the reaction zone temperature was 900deg-C at 68NL/min in intake air flow. The SI-ICE had 290cc in displacement and 8.4 in compression ratio and was driven at 1500rpm. The ignition angle was changed from 30deg-BTDC to 25deg-BTDC with almost same exhaust gas components. The exhaust gas temperature was from 520deg-C to 555deg-C.

In this study, the background gas of the droplet vaporization was concerned and simulated numerically using ANSYS fluent code. The new type, engine-like, condition of high pressure chamber and high temperature environment was considered to conduct experiment on kerosene droplet evaporation. 2D geometry of domain simulation was discretized in the very fine quadrilateral meshes. The numerical approach was solved using implicit scheme of compressible gas solver (density based). Temperature dependent properties of air are expressed for gas material properties. As the study concerning on high pressure condition the equation state of Peng-Robinson was expressed in simulation. Governing equations of mass, momentum and energy were solved by the second order upwind for flow, turbulent kinetic energy and turbulent dissipation rate. Standard k-ε model was used to solve turbulence flow in the spatial discretization.