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2017-10-08
Technical Paper
2017-01-2460
Wenbin Liu, Qiang Song, Yiting Li, Wanbang Zhao
In this paper, a novel driver model is proposed to track vehicle speed in MIL (Model-in-the-Loop) test system, which has structural consistency with HIL (Hardware-in-the-Loop) test system. First, the MIL test system which contains models of driver, vehicle and test bench is established. Second, according to the connections of the established models in Matlab/Simulink environment, the vehicle speed is calculated in vehicle model. Emphatically, through the deviation between driving cycle speed and calculated vehicle speed, PI controller in driver model adjusts the vehicle speed to ideal point through sending the torque command to drive motor, the ILC (Iterative Learning Control) controller modifies and stores P value of PI controller. Then, in order to obtain the better modification of PI controller, iterative learning control algorithm is deeply researched in term of types and parameters.
2017-10-08
Technical Paper
2017-01-2450
Chao Xu, Fuyuan Yang, Jinyu Zhang
Power-split is highlighted as the most popular concept for full hybrid electric vehicles (HEV). However, the energy management and design of power-split heavy duty truck under Chinese driving conditions still need to be investigated. In this paper, the parametric design and an equivalent consumption minimization strategy (ECMS) for the power-split heavy duty truck are presented. Besides, the influence of a penalty factor also discussed. Meanwhile, two different methods to search the engine operation point has been proposed. And the simulation shows both fuel consumption can satisfy the second phase fuel consumption standard and the third phase fuel consumption standard which will be implemented in 2020, in the C-WTVC (Chinese-World Transient Vehicle Cycle). Based on ECMS a design for generator motor and traction motor in power-split heavy duty truck has been processed. The fuel consumption has been indicted to decrease, with the motor power increasing.
2017-10-08
Technical Paper
2017-01-2457
Rickard Arvidsson, Tomas McKelvey
A two-state forward dynamic programming algorithm is evaluated in a series hybrid drive-train application with the objective to minimize fuel consumption when look-ahead information is available. The states in the new method are battery state-of-charge and engine speed. The new method is compared to one-state dynamic programming optimization methods where the requested generator power is found such that the fuel consumption is minimized and engine speed is given by the optimum power-speed efficiency line. The other method compared is to run the engine at a given operating point where the system efficiency is highest, finding the combination of engine run requests over the drive-cycle that minimizes the fuel consumption. The work has included the engine torque and generator power as control signals and is evaluated in a full vehicle-simulation model based on the Volvo Car Corporation VSIM tool.
2017-10-08
Technical Paper
2017-01-2301
Hongli Gao, Fujun Zhang, Wenwen Zeng, Tianpu Dong, Zhengkai Wang
Abstract The electronic control of direct injection fuel system, which could improve engine fuel efficiency, dynamics and engine emission performance through good atomization, precise control of fuel injection time and improvement of fuel-gas mixture, is the key technology to achieve the stratified combustion and lean combustion. In this paper, a direct injection injector that based on voice coil motor was designed aiming at the technical characteristics of one 800cc two-stroke cam-less engine. Prior to a one - dimensional simulation model of injector was established by AMEsim and the maximal fuel injection demand was met via the optimization of the main parameters of the injector, the structure of the voice coil motor was optimized by magnetic equivalent circuit method. After that, the maximal flow rate of the injector was verified by the injector bench test while the atomization characteristic of the injector was verified by using a high-speed camera.
2017-10-08
Technical Paper
2017-01-2304
Hui Ding, Frank Husmeier, Jayesh Gudekar, Amol Bobade, Deepak Patil
Abstract This paper discusses the holistic approach of simulating a low pressure pump (LPP) including test stand flow dynamics. The simulation includes all lines and valves of the test stand representing realistic test operating conditions in the simulation. The capability to capture all line dynamics enables a robust design against resonances and delivers high-quality performance data. Comparison with actual test data agrees very well giving us confidence in the prediction capability of proposed method and CFD package used in the study. Despite the large spatial extent of the simulation domain, Simerics-MP+ (aka PumpLinx) is able to generate a feasible mesh, together with fast running speed, resulting in acceptable turn-around times. The ability to still model small gaps and clearance of the LPP very efficiently enables inclusion of realistic tolerances as experienced on hardware.
2017-10-08
Technical Paper
2017-01-2284
Haifei Zheng
Abstract The potential benefits of reheat burner placed between turbine stages for propulsion system have been recognized for nearly a century. Compared to the conventional non-reheat engines, the turbine inter-guide-vane burner (TIB) engines by using jet-swirl flow scheme (high-G loading) are shown to have a higher specific thrust with no or only small increase in thrust specific fuel consumption. But, it is a known fact that the G loading in the circumferential cavity is inversely proportional to the radius of the circumferential cavity. If one needs to scale this configuration for a larger spool of turbine components, the effeciency of the high G operation and obtained benefits on flame speed will reduce and hence the performance will de-grade.
2017-10-08
Technical Paper
2017-01-2282
Gen Chen, Wenxin Cai, Jianguang Zhou, Christian Spanner, Heribert Fuchs, Werner Schrei, Karl Weihrauch
Abstract A TGDI (turbocharged gasoline direct injection) engine is developed to realize both excellent fuel economy and high dynamic performance to guarantee fun-to-drive. In order to achieve this target, it is of great importance to develop a superior combustion system for the target engine. In this study, CFD simulation analysis, steady flow test and transparent engine test investigation are extensively conducted to ensure efficient and effective design. One dimensional thermodynamic simulation is firstly conducted to optimize controlling parameters for each representative engine operating condition, and the results serve as the input and boundary condition for the subsequent Three-dimensional CFD simulation. 3D CFD simulation is carried out to guide intake port design, which is then measured and verified on steady flow test bench.
2017-10-08
Technical Paper
2017-01-2290
Zhixin Sun, Shaoqing Yang, Xinyong Qiao, Zhiyuan Zhang
Abstract When operating at high elevation of 3700m (atmospheric pressure about 68 kPa), the combustion process of diesel engine deteriorates, and the engine performance declines significantly. In this paper, Isooctyl Nitrate(EHN) is blended into the diesel fuel as additive to improve the combustion process. The decomposition of Isooctyl Nitrate(EHN) is analyzed and its mechanism is studied through chemical kinetics. A series of tests were carried out on a single cylinder diesel engine to study the effects of EHN on diesel engine combustion with the low intake pressure of 68kPa. Results show that the generation of OH、 H、 HO2 and H2O2 in n-heptane cleavage reactions can be promoted by EHN. In both stages of low and high temperature, the decomposition of n-heptane is accelerated, which shortened the ignition delay period. Four kinds of fuel are studied by tests: diesel fuel, diesel fuel with 0.3%, 0.6% and 0.9% mass fraction EHN respectively.
2017-10-08
Technical Paper
2017-01-2306
Xiaochuan Sun, Xiang Li, Zhong Huang, Dehao Ju, Xing-cai Lu, Dong Han, Zhen Huang
Abstract Recently, the shortage of fossil resources contributes to strict regulations of environmental protection. The research on the high efficiency and low emission of engines becomes an important direction all over the world. Technologies like high injection pressure, high levels of supercharging and higher levels of back pressure have come into application. Increasing the injection pressure and average cylinder pressure results in that parts of the spray can experience transcritical and supercritical regimes. In this paper, we established a surrogate fuel composed of n-Hexadecane, HMN and 1-Metylnaphthalene, to analyze the injection and atomization of diesel surrogate fuel with large eddy simulation (LES) in a cubic calculation region with high temperature and high pressure environment.
2017-10-08
Technical Paper
2017-01-2302
Tobias Knorsch, Dmitrii Mamaikin, Philippe Leick, Philipp Rogler, Jin Wang, Zhilong Li, Michael Wensing
Abstract The fuel spray behavior in the near nozzle region of a gasoline injector is challenging to predict due to existing pressure gradients and turbulences of the internal flow and in-nozzle cavitation. Therefore, statistical parameters for spray characterization through experiments must be considered. The characterization of spray velocity fields in the near-nozzle region is of particular importance as the velocity information is crucial in understanding the hydrodynamic processes which take place further downstream during fuel atomization and mixture formation. This knowledge is needed in order to optimize injector nozzles for future requirements. In this study, the results of three experimental approaches for determination of spray velocity in the near-nozzle region are presented. Two different injector nozzle types were measured through high-speed shadowgraph imaging, Laser Doppler Anemometry (LDA) and X-ray imaging.
2017-10-08
Technical Paper
2017-01-2310
Xiaoyan Jia, Baigang Sun, Dongwei Wu, Dan Xu, Wei Zang, Wei Shang, Jie Wang
Abstract The control valve is the most important implementation part of a high pressure common rail system, and its flow characteristics have a great influence on the performance of an injector. In this paper, based on the structure and the working principle of an electromagnetic injector in a high pressure common rail system, a simulation model of the injector is established by AMESim software. Some key parameters of the control valve, including the volume of the control chamber, the diameter of the orifice Z (feeding orifice), the diameter of the orifice A (discharge orifice) and the hole diameter of the fuel diffusion hole are studied by using this model. The results show that these key structural parameters of the control valve have a great influence on the establishment of the control chamber pressure and the action of the needle valve.
2017-10-08
Technical Paper
2017-01-2316
Yuhan Huang, Guang Hong, John Zhou
Abstract Ethanol direct injection (EDI) has great potential in facilitating the downsizing technologies in spark ignition engines due to its strong anti-knock ability. The fuel temperature may vary widely from non-evaporating to flash-boiling sprays in real engine conditions. In this study, a CFD spray model was developed in the ANSYS Fluent environment, which was capable to simulate the EDI spray and evaporation characteristics under non-evaporating, transition and flash-boiling conditions. The turbulence was modelled by the realizable k-ε model. The Rinzic heterogeneous nucleation model was applied to simulate the primary breakup droplet size at the nozzle exit. The secondary breakup process was modelled by the Taylor Analogy Breakup model. The evaporation process was modelled by the Convection/Diffusion Controlled Model. The droplet distortion and drag, collision and droplet-wall interaction were also included.
2017-10-08
Technical Paper
2017-01-2317
Om Prakash Saw, Yashas Karaya, J M Mallikarjuna
Abstract The mixture formation in gasoline direct injection (GDI) engines operating at stratified condition plays an important role in deciding the combustion, performance and emission characteristics of the engine. In a wall-guided GDI engine, piston profile is such that the injected fuel is directed towards the spark plug to form a combustible mixture at the time of ignition. In these engines, fuel injection pressure and timing play an important role in creating a combustible mixture near the spark plug. Therefore, in this study, an attempt has been made to understand the effect of fuel injection pressure with single and split injection strategy on the mixture formation in a four-stroke, wall-guided GDI engine operating under stratified conditions by using computational fluid dynamics (CFD) analysis. Four fuel injection pressures viz., 90, 120, 150 and 180 bar are considered for the analysis.
2017-10-08
Technical Paper
2017-01-2333
Marcos Gutierrez, Andres Castillo, Juan Iniguez, Gorky Reyes
Abstract Aiming for cleaner and more efficient energy from the internal combustion engines makes necessary to ensure the special conditions for exploitation of alternative fuels. The engine vibrations are primarily understood as effects of mechanical failures, but they are also a subject of the fuel combustion effects. These effects depend on the fuel type and its ability to complete the combustion process. The vibrations of a diesel engine were measured and analyzed with a frequency spectrum calculated with fast Fourier transforms. The engine was operated with a fuel blend of 10 % recycled lubricating oil with 90% diesel fuel as well as with neat diesel. It was found that the engine operation with this fuel blend has a lower vibration level in comparison with the use of neat diesel fuel. The goal of this research is to determine the properties of the fuel blend, which provide more stability to the engine by means of vibrations reduction.
2017-10-08
Technical Paper
2017-01-2186
Lukas Urban, Michael Grill, Sebastian Hann, Michael Bargende
The development of IC engines is a complex process where 0D/1D-simulation tools became more important in the past few years. Different designs can be investigated in very early stages of the development process without the expensive buildup of prototypes and it is possible to get reliable results with passable effort. The quality of the overall simulation results depends on the quality of the sub-models. Simulation of the combustion process in natural-gas SI engines relies on predictive models for burn rates and knock. Existing knock models for gasoline fuels are based on a time-integrated ignition delay, using a fitted Arrhenius equation. Within a research project an enhanced knock-model approach for methane based fuels was developed. Chemical kinetics models were used to calculate the auto-ignition times for various temperatures, pressures and air-fuel-ratios (AFR).
2017-10-08
Technical Paper
2017-01-2185
Chao He, Jiaqiang Li, Longqing Zhao, Yanyan Wang, Wei Gu
More and more stringent emission regulations and the desire to reduce fuel consumption lead to an increasing demand for precise and close-loop combustion control of diesel engines. Cylinder pressure-based combustion control is gradually used for diesel engines in order to enhance emission robustness and reduce fuel consumption. However, it increases the cost. In this paper, a new prediction method of combustion parameters including cylinder pressure is presented for diesel engines. The experiment was carried out on a engine test bench to obtain the ECU (Electronic Control Unit) signals of a heavy-duty diesel engine by calibration software. The combustion parameters is measured by a combustion analyzer, such cylinder pressure, combustion center of gravity (CA50) and the maximum combustion temperature (MCT). A combustion model using genetic programming (GP) is built.
2017-10-08
Technical Paper
2017-01-2188
Bruno S. Soriano, Edward S. Richardson, Stephanie Schlatter, Yuri M. Wright
Dual-fuel combustion is an attractive approach for utilising alternative fuels such as natural gas in compression-ignition internal combustion engines. In this concept, a more reactive fuel is injected in order to provide a source of ignition for the premixed natural gas/air, combining the high efficiency of a compression-ignition engine with the relatively low emissions associated with natural gas. The flame modes present in dual-fuel engines impose a challenge for existing turbulent combustion models. Following ignition, flame propagates through a partially-reacted and inhomogeneous mixture of the two fuels. The objective of this study is to test a new modelling approach that combines the ability of the Conditional Moment Closure (CMC) approach to describe autoignition of fuel sprays with the ability of the G-equation approach to describe the subsequent flame propagation.
2017-10-08
Technical Paper
2017-01-2190
Alessandro D'Adamo, Marco Del Pecchia, Sebastiano Breda, Fabio Berni, Stefano Fontanesi, Jens Prager
CFD simulations of reacting flows are fundamental investigation tools used to predict combustion behaviour and pollutants formation in modern spark-ignition internal combustion engines. Most of the flamelet-based combustion models adopted in current simulations use the fuel/air/residual laminar flame speed as a background to predict the turbulent flame speed. This in turn is a fundamental requirement to model the effective burn rate. The consolidated approach in engine combustion simulations relies on the adoption of empirical correlations for laminar flame speed, which are derived from fitting activity of combustion experiments. However, these last are conducted at largely different pressure and temperature ranges from those encountered in engines: for this reason, correlation extrapolation at engine conditions is inevitably accepted and relevant differences between proposed correlations emerge even for the same fuel and conditions.
2017-10-08
Technical Paper
2017-01-2192
Shenghui Zhong, Zhijun Peng, Yu Li, Hailin Li, Fan Zhang
A 3D DNS (Three-dimensional direct numerical simulation) study with detailed chemical kinetic mechanism of methane has been performed to investigate the characteristic of turbulent premixed oxy-fuel combustion relevant to traditional spark ignition (SI) engine conditions. H2O and CO2 are adopted as the dilution agents in oxy-fuel combustion. In order to keep a consistent temperature profile compared with those of air-fired cases, 73% and 66% of H2O and CO2 in oxidizer by volume ratio are used. At first, laminar premixed flames are conducted to study the effect of the dilution molar fraction on the process of flame propagation. It is found that decreasing the dilution molar fraction will increase the flame propagation speed in both H2O and CO2 dilution cases, and there exists a temperature limitation because of chemical equilibrium.
2017-10-08
Technical Paper
2017-01-2193
Andreas Nygren, Anders Karlsson
When developing new combustion concepts, CFD simulations is a powerful tool. The modeling of spray formation is a challenging but important part when it comes to CFD modelling of non-premixed combustion. There is a large difference in the accuracy and robustness among different spray models and their implementation in different CFD codes. In the work presented in this paper a spray model, designated as VSB2 has been implemented in OpenFOAM. VSB2 differ from traditional spray models by replacing the Lagrangian parcels with stochastic blobs. The stochastic blobs consists of a droplet size distribution rather than equal sized droplets, as is the case with the traditional parcel. The VSB2 model has previously been thoroughly validated for spray formation and combustion of n-heptane. The aim of this study was to validate the VSB2 spray model for ethanol spray formation and combustion as a step in modelling dual-fuel combustion with alcohol and diesel.
2017-10-08
Technical Paper
2017-01-2194
Mateusz Pucilowski, Mehdi Jangi, Sam Shamun, Martin Tuner, Xue-Song Bai
Experimental heavy-duty DICI methanol engine is studied under high compression ratio conditions (CR=27). The fuel is injected with common-rail injector close to the top-dead-center (TDC) position with three different injector pressures, leading to a spray formation causing a so called wall-wetting. Numerical simulations using RANS/LPT/WSR and PDF models are employed to investigate the local conditions of the injection and combustion process. The CFD results are compared with the pressure trace and emissions from the metal engine experiment. It is shown that the simulations captured the same trend of increased amount of unburned hydrocarbons at higher injection pressures. Moreover, the intake temperature adjustments were required to correctly capture the ignition delay time when WSR model was used, whereas with the PDF method such adjustments were not needed.
2017-10-08
Technical Paper
2017-01-2196
Giuseppe Cicalese, Fabio Berni, Stefano Fontanesi, Alessandro D'Adamo, Enrico Andreoli
High performance Diesel engines are characterized by remarkable thermo-mechanical loads. Therefore, compared to spark ignition engines, designers are forced to increase component strength in order to avoid failures. By the way, 3D-CFD simulations represent a powerful tool for the evaluation of the engine thermal field and may be used by designers, along with FEM analysis, to prevent thermo-mechanical failures. The current work aims at providing an integrated in-cylinder/CHT methodology for the estimation of a Diesel engine thermal field. On one hand, in-cylinder simulations are fundamental to evaluate not only the global heat transfer at the combustion chamber walls, but also its point-wise distribution. In particular, thanks to an improved heat transfer model based on a modified thermal wall function, wall heat fluxes due to combustion are correctly estimated.
2017-10-08
Technical Paper
2017-01-2197
Vignesh Pandian Muthuramalingam, Anders Karlsson
Owing to increased interest in blended fuels for automotive applications, a great deal of understanding is sought for the behavior of multicomponent fuel sprays. This sets a new requirement on spray model since the volatility of the fuel components in a blend can vary substantially. It calls for careful solution to implement the differential evaporation process concerning thermodynamic equilibrium while maintaining a robust solution. This work presents the Volvo Stochastic Blob and Bubble (VSB2) spray model for multicomponent fuels. A direct numerical method is used to calculate the evaporation of multicomponent fuel droplets. The multicomponent fuel model is implemented into OpenFoam CFD code and the case simulated is a constant volume combustion vessel. The CFD code is used to calculate liquid penetration length for surrogate diesel (n-dodecane)-gasoline (iso-octane) blend and the result is compared with experimental data.
2017-10-08
Technical Paper
2017-01-2199
Maria Cristina Cameretti, Vincenzo De Bellis, Luca Romagnuolo, Agostino Iorio, Luigi Maresca
Engine manufacturers are continually committed to find proper technical solutions to meet the more and more stringent CO2 emission targets fixed worldwide. Many strategies have been already developed, or are currently under study, to attain the above objectives. A tendency is however emerging towards more innovative combustion concepts, able to efficiently burn lean or highly diluted mixtures. To this aim, the enhancement of turbulence intensity inside the combustion chamber has a great importance, contributing to improve the burning rate, increase the thermal efficiency, and also reduce the cyclic variability. It is well-known that turbulence production inside the combustion chamber is mainly achieved during the intake stroke. Moreover, it is strongly affected by the intake duct geometry and orientation with respect to a plane perpendicular to the cylinder axis.
2017-10-08
Technical Paper
2017-01-2201
Zhongye Cao, Tianyou Wang, Kai Sun, Lei Cui, Yong Gui
For uniflow scavenged two-stroke marine diesel engines, the main function of scavenging process is to replace the burned gas with fresh charge. The end state of scavenging process is integral to the subsequent compression and combustion, thereby affecting the engine’s fuel economy, power output and emissions. In this paper, a complete working cycle of a large marine diesel engine was simulated by using the 3D-CFD software CONVERGE. The model was validated by mesh sensitivity test and experiment data. Based on this calibrated model, the influences of swirl ratio and exhaust valve closing (EVC) timing on the scavenging process were investigated. The parameters evaluating the performance of scavenging process were introduced. The results show that, by adjusting the swirl orientation angle(SOA) from SOA=10° to SOA=30°, different swirl ratios are generated and have obvious differences in flow characteristics and scavenging performance.
2017-10-08
Technical Paper
2017-01-2202
Shiyou Yang
This work presents an application of two sub-models relative to chemical-kinetics-based turbulent pre-mixed combustion modeling approach on the simulation of burn rate and emissions of spark ignition engines. In present paper, the justification of turbulent pre-mixed combustion modeling directly based on chemical kinetics plus a turbulence model is given briefly. Two sub-models relative to this kind of pre-mixed combustion modeling approach are described generally, including a practical PRF (primary reference fuel) chemical kinetics mechanism which can correctly capture the laminar flame speed under a wide range of Ford SI (spark ignition) engines/operating conditions, and an advanced spark plug ignition model which has been developed by Ford recently.
2017-10-08
Technical Paper
2017-01-2208
Tao Liu, Ziwang Lu, Guangyu Tian
To further explore the potential of fuel economy for hybrid electric vehicle (HEV) , an adaptive energy management strategy (EMS) considering driver’s power demand reasonability is proposed, which is necessary to reduce fuel consumption, emission and traffic congestion. To get accurate and reliable control strategy two aspects are the most important: 1) a rigorous and organized modeling approach to describe complicated powertrain system of HEV, 2) a trade off between optimization and real time. The Energetic Macroscopic Representation (EMR) is a graphical synthetic description of electromechanical conversion system based on energy flow. Based on Energetic Macroscopic Representation (EMR) a powertrain architecture of HEV is constructed. Generally EMS includes rule based that can be used online with suboptimal solution and optimization based that ensures the minimum fuel consumption with heavy computation duty and requirement of prior knowledge.
2017-10-08
Technical Paper
2017-01-2422
Na Li, Fenlian Huang, Yuhua Bi, Yueqiang Xu, Lizhong Shen, Dewen Jia
Abstract The assembly of con rod bearing and crankpin is a key friction pair which offers an important guarantee for stable operation of diesel engine. Specific to the non-road 2-cylinder diesel engine developed independently and based on the theory of thermoelastohydrodynamic lubrication as well as multi-body dynamics, this paper establishes a multi-body dynamics model for con rod big end bearings of the 2D25 horizontal diesel engine and makes a research on the influence of bearing width, bearing clearance, and oil inlet position and diameter upon lubrication of con rod bearing, taking into consideration that of the surface appearance of bearing bush and the elastic deformation of bearing bush and axle journal upon the same. Research results show that bearing width and bearing clearance are the major factors that influence lubrication characteristics of con rod bearing while oil inlet position and diameter only have a small influence on such characteristics.
2017-10-08
Technical Paper
2017-01-2424
Shemin Zhang, Huaping Li, Tao Chen, Nan Jiang, Xinzhen Tan, Limei Deng, Qingsong Xia, Paul Kapus, Mingtang Ma, Wei Li, Junqiang Zhang, Qingjun Ma, Yong Xia
Abstract In recent years, more attentions have been paid to stringent legislations on fuel consumption and emissions. Turbocharged downsized gasoline direct injection (DI) engines are playing an increasing important role in OEM’s powertrain strategies and engine product portfolio. Dongfeng Motor (DFM) has developed a new 1.0 liter 3-cylinder Turbocharged gasoline DI (TGDI) engine (hereinafter referred to as C10TD) to meet the requirements of China 4th stage fuel consumption regulations and the China 6 emission standards. In this paper, the concept of the C10TD engine is explained to meet the powerful performance (torque 190Nm/1500-4500rpm and power 95kW/5500rpm), excellent part-load BSFC and NVH targets to ensure the drivers could enjoy the powerful output in quiet and comfortable environment without concerns about the fuel cost and pollution.
2017-10-08
Technical Paper
2017-01-2426
Zhiming Zhang, Weimin Wang, Jiangtao Wang, Jiming Zhang, Yuanda Chen, Wenlong Zhang, Guofang Yang, Fugui Fan, Wenxiang Zhang, Fengqin Huang, Xiangwang Li
Abstract In recent years, Turbo-charged GDI technology is more and more widely used, which can meet the high demand of the engine performance and efficiency, but the resulting reliability and NVH issues also need to be paid attention to [1]. Traditional NVH performance improvement is mostly based on the experience design and repeatable test, which lead to longer development period, high cost, and also ineffective results. NVH performance simulations play more important role in engine vibration and noise prediction along with the development of the simulation technology[2][3]. The force response analysis is usually used to evaluate the NVH performance of the engine structure under the standard excitation. However, dynamic analysis of the crank train, valve train, and piston can be carried out based on the AVL software family, also the vibration and airborne noise of whole engine can be predicted directly at different speed and load [4].
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