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The complete engine process (inlet stroke, direct methane injection, compression, combustion and exhaust stroke) in a direct injection methane engine is investigated using the Reynolds Averaged Navier Stokes (RANS) and the Large Eddy Simulation (LES) approaches offered by Star-CD. Single-cycle RANS and LES simulations based on k − ǫ and k − l turbulence models, were performed first to assess the potential improvement offered by LES. The model approaches of RANS and LES in the fields of wall heat losses and combustion are compared and the differences are discussed. Especially in the combustion...
The paper presents a numerical activity directed at the analysis and optimization of internal combustion engine water cooling jackets, with particular emphasis on the fatigue-strength assessment and improvement. In the paper, full 3D-CFD and FEM analyses of conjugate heat transfer and load cycle under actual engine operation of a single bank of a current production V6 turbocharged Diesel engine are reported. A highly detailed model of the engine, made up of both the coolant galleries and the surrounding metal components, i.e. the engine head, the engine block, the gasket, the valve guides and...
A multidimensional computational fluid dynamics (CFD) simulation of a constructed syngas chemical kinetic mechanism was performed to evaluate the combustion of syngas in a supercharged dual-fuel engine for various syngas initial compositions under lean conditions. The modelled results were validated by comparing predictions against corresponding experimental data for a supercharged dual-fuel engine. The predicted and measured in-cylinder pressure, temperature, and rate of heat release (ROHR) data were in good agreement. The effect of the hydrogen peroxide chain-propagation reaction on the...
The commercial CFD software STAR-CCM+ was used to simulate transportation of viscous oil in a horizontal pipe. The CFD model was first validated against analytical solution for wall shear stress in laminar flows with constant physical properties. The model was then used to investigate the effects of heat loss since the pipe is subjected to cooling by the sea water on the sea bed. The results show strong thermal stratification across the pipe with cooler fluid at the bottom of the pipe and warmer fluid near the gas-liquid interface. A layer of cooler fluid is also found next to the pipe wall...
This paper presents a novel turbocharging system applied to four-stroke diesel engines, which is named modular multi-purpose pulse converter (MMPC) turbocharging system. Two-dimensional steady flow simulations of the MMPC turbocharging system are performed with STAR-CD code. A one-dimensional unsteady flow simulation code finite volume method and total variation diminishing (FVM–TVD) has been developed. Using FVM–TVD, flow predictions in the diesel engine 8L250Z are carried out in the unsteady state with the mixed pulse converter (MIXPC) turbocharging system and MMPC, respectively. It is...
As the world enters a new millennium, the spark ignition engine enters a new age of gasoline fuel injection technology – direct injection. Orbital Engine Company is at the forefront of this technology with a unique, air–assist direct injection (ADI) system, which utilises a low–pressure air pulse as fuel atomiser and carrier. Modelling of Orbital's ADI system was carried out using a Eulerian–Lagrangian formulation for two–phase flow with a commercially available CFD package called Star–CD. The research has been a large step forward towards an improved predictive injection model for use in...
Magnesium is a desirable material for light-weight construction due to its low density and high strength-to-weight ratio. The disadvantage of low cold formability may be overcome for sheet production by combining casting and forming within horizontal twin-roll casting (TRC). During this process, the molten alloy is fed between two counter-rotating rolls water cooled from the inside. In this paper, numerical simulations using the commercial CFD software Star-CCM+ are presented. The code provides the model based on an incompressible, steady-state solver for laminar flow. To describe the...
In dispersed two-phase flows, the particle size is probably the most important parameter in determining the particle dynamics. Interphase forces, heat and mass transfers are all functions of the particle diameter. Diameters of the particles are unlikely to be uniform and for droplets and bubbles they can change continuously due to breakup and coalescence. Methods of moments have been used very successfully in modeling particle size distributions in dispersed two-phase flows. The model described in this paper is based on the method of moment. It contains models for droplet breakup and...
Numerical simulations of gas-liquid two-phase flow with high superficial velocity in a vertical pipe were conducted with the use of the commercial software package STAR-CD 3.27. Detailed description of the Sγ model is presented. The applicability and performance of the Sγ model in Eulerian modelling of gas-liquid bubbly flow were studied. The sensitivity of the Sγ model to the distribution moment γ, and the drainage mode were also investigated. The numerical results were compared with the available experimental data of Hibiki et al., (2001). Good agreement was achieved for the phase axial...
Numerical simulations of gas-liquid two-phase flow with high superficial velocity in a vertical pipe were conducted with the use of the commercial software package STAR-CD 3.27. The change in bubble size due to breakup and coalescence was modelled by the S γ model. The applicability and performance of the S γ model in modelling of gas-liquid bubbly flow were studied. The sensitivity of the S γ model to the distribution moment γ , and the drainage mode were investigated. The numerical results were compared with the experimental data of Hibiki et al., (2001). Good agreement was achieved for...

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