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Simulation of Low NOx Combustion with Heating Fuel in Diesel Engine Qian WANG, Chengcheng ZHANG , Zhixia HE and Jing WANG College of Energy and Power Engineering,Jiangsu Univ,Zhenjiang,Jiangsu, China email:zcc_cool@126.com Key words: Diesel engine; Heating Fuel; Combustion; NOx Abstract: Based on sensitivity of fuel physicochemical property to temperature,in order to study the effects of fuel injection temperature on spray and combustion performance of diesel engine, commercial CFD software STAR-CD is used to simulate the spray and combustion processes of diesel engine with heating fuel spray.
The simulation is on the basis of the previous study[3].
The dynamometer card comparison between test and simulation is shown in the Fig.3.
Fig.1 Computational grid at TDC Fig.2 Test setting drawing Fig.3 The dynamometer card comparisons of test and simulation.
Simulation Research on Matching of Spray and Combustion Chamber Geometry in Diesel Engine.

FloVENT is powerful computational fluid dynamics (CFD) software that predicts 3D airflow, heat transfer, contamination distribution and comfort indices in and around buildings of all types and sizes.
Through 3D heat transfer and whole building energy simulations the impact of introducing a balcony thermal break on the overall heat transmittance, floor surface temperature distribution, and the total heating energy consumption is evaluated for a typical balcony detail.
[2] Kosny, J., A New Whole Wall R-value Calculator, An Integral Part of the Interactive Internet Based Building Envelope Materials Database for Whole-Building Energy Simulation Programs, 2004
Clarke, Energy Simulation in Building Design, Adam Hilger Ltd, UK, 1985
Frank, Experimental and numerical thermal analysis of a balcony board withintegrated glass fibre reinforced polymer GFRP elements, Energy and Buildings 39 (2007) 76–81 [11] FLOVENT, CFD (computational fluid Dynamics), 3D Airflow Modeling Software, Mentor graphics corporation, USA, Version 9.1, 2011

Fig.8 Mean variable profile in the boundary layer Fig.8 gives the mean variable profile in the boundary layer, GAO-YONG turbulence model has the same simulation capabilities with the DNS, better than the two-equation eddy viscosity k-ω model.
“CFD analysis of cyclist aerodynamics: Performance of different turbulence-modelling and boundary-layer modelling approaches.”
Carmeliet, “CFD analysis of convective heat transfer at the surfaces of a cube immersed in a turbulent boundary layer”, Int J Heat Mass Trans, Vol. 53, 2010, pp. 297–308
Direct Numerical Simulation of Supersonic Turbulent Boundary Layer Flow.
[15] Pirozzoli S, Grasso F, Gatski TB, Direct numerical simulation and analysis of a spatially evolving supersonic turbulent boundary layer at M=2.25.

Other similar studies include the CFD-based simulation of vertical points in high-rise buildings that are heavily affected by rain water[3].
The said simulation, however, showed limitations in drawing a correlation between such points and the amount of water collection.
Carmeliet, CFD simulation and validation of wind-driven rain on a building façade with Eulerian mulyiphase model, Building and Environment. 61 (2013) 69-81

In addition, we carry out this simulation with Ha=21.2 and Re=5681.
Thus, the electro-magnetic terms is indispensable in the simulation of MHD flows.
Wilcox, Turbulence modeling for CFD, 2nd edn.
Pan, Numerical simulation of MHD duct flow about laminar and turbulence model, Nuclear Fus.
Liu, Direct numerical simulations of magnetohydrodynamics on turbulent duct flow, Nuclear Fus.

For comparison and selection the HAM simulation program WUFI was used.
Introduction The use of various simulation programs have increased with computers development.
In all simulations was used r.r.f. = 0,5.
In selected simulation was used the value 0,7 which move up the yearly courses.
[cit. 2010-01-10] [4] KUBILAY, A. et al.: CFD simulation and validation of wind-driven rain on a building facade with an Eulerian multiphase model.

In recent years, the numerical simulation [1-3] technology is widely applied.
The research is mainly to evaluate and optimize the scheme of a wastewater treatment plant M-ICAR process design, using CFD (Computational fluid dynamics) technology to simulate sludge layer stability, in order to provide the theoretical support for the reaction tank structure and operation parameters.
This paper simulated settling and decant process with different feeding and recycle, and analyzed the influence for sludge settle ability, proposing optimization solution based on the simulation results.
Simplification for M-ICAR process The simulation of settling process Fig. 3.
The simulation of decant process Fig. 6.

Meanwhile, in order to verify reliability of the thermal gas mass flow meter in the system, we adopted CFD method to simulate the EGR cooler by using empirical parameters, and collected several related sensor parameters of the EGR cooler in the condition that the inlet temperature was constantly at 368K while the coolant had 4 kinds of degrees.
Temperature and pressure cloud chart of the EGR cooler flow field Table2 is the experimental results of EGR cooler; table3 is the simulation results of EGR cooler.
Simulation results of the EGR cooler (K) (L/min) (K) (bar) (kg/h) (bar) (kPa) (kPa) (K) 368 20 836 2.1 91 1.6 20 10 472 368 25 836 2.1 90 1.6 20 14 468 368 30 836 2.1 90 1.6 20 19 463 368 35 836 2.1 90 1.6 20 28 461 According to Table 2 and Table3, the critical data EGR gas outlet temperature, the overall heat transfer coefficient and coolant flow curve are plotted into figure 5.
Compared to simulation values, the gas outlet temperature of the experimental value is about 1.17% lower on average; and the heat transfer coefficient is 3.1% larger on average.
Meanwhile, in order to verify reliability of the thermal gas mass flow meter in the system, we adopted CFD method to simulate the EGR cooler using empirical parameters, and collected several related sensor parameters of the EGR cooler in the condition that the inlet temperature is constantly 368K while the coolant had 4 kinds of degrees.

Relative errors of pressure amplitudes and pressure vibrated times between simulation results and experimental results are below 10%.
CFD (Computational Fluid Dynamics) and Fluent were used to simulate flow field characters in PWM controlled solenoid valve and cut-off valve, and acquired changing regularities of them in solenoid valve when it switches between open and closed by some scholars, simulation results were confirmed by mathematical computation or experiments, which supported optimizations of Cut-Off valve in theory[8-14].
Simulation results. (1) When solenoid valve opens, pressure curve is shown in Fig.3.a.
PWM controlled variable rate spraying system shown in Fig.1 was used to carry out 3 groups of relative experiments.Pressure signals were collected by pressure transducer at 1 kHz when solenoid valve operates under the same working conditions of simulations.
(2) Compared simulation and experimental results, relative errors of pressure amplitudes and pressure vibrating times in 3 working conditions are within 10%.

It uses the computational fluid dynamics (CFD) solver to compute[4].
Design of Optimization and Simulation.
Analyze Simulation Results after Optimization.Completing the thermal simulation under the new designed system by Icepak, the simulated results as show in Table 3, the plane flow chart of system cooling as show in Fig. 6.
Running the simulation again at the environmental temperature of 35℃, these components’ temperature meet the spec.
Heat sink numerical simulation with Icepak using compact heat sink modeling techniques.