科创中国

In this paper, the engine optimal matching is done to improve the efficiency of a turbocharged lean-burn LPG engine by optimizing the compression ratio and the distribution phase of camshaft. In this way, the gas consumption and emissions of the LPG engine are reduced. A one-dimensional engine model and a three-dimensional in-cylinder combustion model are set up with simulation software. The optimal compression ratio is determined by comparing the results from simulation and experiment at different compression ratios. The exhaust advance angle and valve overlap angle are optimized on the basis of successive optimization method and demonstrated in experiments.

Dawei Qu;骏 李;Ying Gao;Luyan Fan;Changqing Song

2010

An experimental study on the performances of diesel oxidation catalyst (DOC) and diesel particulate filter (DPF) is conducted. The rule of the effects of DOC on diesel emission is analyzed, and the pressure drop characteristic and filtration performance of DPF is tested. Finally the safety problems in DPF regeneration process are also discussed.

Yi Hu;Mengliang Li;骏 李;Maodong Fang;Meilin Ren

Qiche Gongcheng/Automotive Engineering

2010-5

According to the powertrain and vehicle parameters of a self-developed parallel hybrid electric vehicle, the longitudinal dynamics analysis was carried out, and the simulation model was built. Using the dynamic programming global optimization algorithm, the shift schedule for a HEV automated manual transmission was studied. The results show that: through the obtained optimal economy shift schedule, the operation regions of engine and motor are optimized, the output power efficiency of powertrain is improved and the fuel consumption was nearly 12% lower than the HEV with the original shift strategy.

Cheng Wang;Bo Zhang;Jinshan Feng;Yu Guan;骏 李;Shichun Yang

2011

The durability of automotive products is an important factor to affect their competitiveness; meanwhile, due to their long development cycle and huge costs, the durability control in their conceptual design stage is in great need. Virtual proving ground to predict the durability has been used to performance of a passenger car suspension. A simulation model of flexible virtual proving ground (VPG) for a passenger car has been created, with a variety of durability enhancement roads in the Nong'an Proving Ground as inputs. A string of key technological problems (tire model, stiffness of bushing and roads model) regarding VPG applications has been solved. In addition, the time-history dynamic stress response of a car suspension system has been analyzed, and compared it with the real passenger car durability test results obtained under the same conditions. The results of the simulation and the test are basically identical in terms of the trend of time and frequency domains. Furthermore, the effectiveness of the flexible VPG technology for the simulated suspension system's dynamic stress response has been demonstrated, and the effective prediction for the suspension system durability in the development process has been realized.

Zhenglin Cao;骏 李;Konghui Guo

Jixie Gongcheng Xuebao/Chinese Journal of Mechanical Engineering

2012-5-20

In this paper, Beijing drive cycle for city bus was obtained through investigating, logging and abstracting parameters such as vehicle speed and time etc. A conventional city bus was simulated applying Beijing drive cycle, UKBUS (United Kingdom Bus) cycle and NurembergR36(Germany Nuremberg Bus) cycle with ADVISOR. The relationship among engine operation points, Euro-III 13 mode points and NO_x control area was investigated. The rationality that Euro-III exhaust emission regulation was used on the Chinese city bus engine was analyzed. The study results show that Chinese city bus drive cycle is different from those of Europe, the measured engine exhaust emission level is different from the engine actual exhaust emission level when Euro-III exhaust emission regulation is applied to the Chinese city bus.

Hui Li Dou;骏 李;Zhong Chang Liu;Fei Ge

Neiranji Gongcheng/Chinese Internal Combustion Engine Engineering

2005-4

For a plug-in hybrid electric vehicle equipped with Automated Manual Transmission (AMT), Dynamic Programming (DP) algorithm is used to improve the energy economy of the vehicle under the dynamic performance. Meanwhile, the energy consumption curve of vehicle and the operating points of engine under the driving cycle are obtained. From the results, the operation can be divided into two phases which are pure electric driving mode and hybrid driving mode. Then, compare the consumption in the two phases of hybrid electric vehicle with that of pure electric vehicle and traditional fuel vehicle separately. Finally, through calculation, the dynamic performance of the plug-in hybrid electric vehicle is also verified.

Zhan Jiang Li;Hao Li;Xin Li;骏 李;Xue Song Li

2014

In order to study and evaluate the effect of sulfated ash in different diesel engine lubricants on the performance and durability of diesel particulate filter (DPF), the two engine oils of API CI-4 and CJ-4 with different sulfated ash levels are used respectively in the durability tests of two DPF systems. Moreover, the pressure drop, ash loading and filtration efficiency of the two DPFs, deposits in the inlets and outlets of the DPFs, intake flow rate and fuel consumption rates of engine are measured and compared. The test results show that: Compared to the API CI-4 which has more ash in the formulation than the API CJ-4, the API CJ-4 shows a markedly excellent performance on the lower ash loading and longer service interval and life for DPF, as well as lower fuel consumption rate for the diesel engine with DPF.

Heju Zhu;Wanying Li;Hanguo Tao;骏 李;Xiuhua Sui

SAE Technical Papers

2014-10-13

A fluid-solid interaction simulation of hydraulic engine mounts (HEM) was developed numerically. The ALE (Arbitrary Lagrangian-Eulerian) finite element method was employed for viscous fluid flow, and linear elastic and hyper-elastic structure materials were used for modeling the steel and rubber respectively. The full interaction between fluid and structure was considered as a strong coupling action. A Laplace equation-based mesh control method was used for moving the internal meshes of the fluid domain. The dynamic characteristics of the HEM were clarified by 3D simulations, and the comparisons between numerical results aud experimental results demonstrate the reliability of the proposed method.

Zheng Lin Cao;骏 李;Kong Hui Guo;Qun Zhang

Zhendong yu Chongji/Journal of Vibration and Shock

2012-5-28

Engine tests were carried out by using TSI3090 EEPSTM particle size spectrometer to study influence of biodiesel blend on the common-rail diesel engine transient particle emission and its size distribution characteristics, as well as effects of fuel physical and chemical properties on the particle size distribution. The results show that the particle size distributions for diesel and biodiesel fuels are both bi-modal with two peaks at 10 and 60 nm over the transient conditions. The particles for biodiesel fuel are mainly small diameter nuclei mode particles, accounting for over 96% of total, and for diesel fuel are mainly large diameter accumulation mode particles, accounting for over 55% of total. The mean particle emission amounts of BTL fuel and diesel fuel decrease as transient rate reducing, but the former's decrease is more obvious. For different BTL fraction biodiesel fuels, in low transient rate condition the particle emissions increase slowly as the BTL fraction rising, in middle transient rate condition, it hardly changes when the BTL fraction is below 30%, and in high transient rate condition, it increases rapidly as the fraction is above 10%.

Chun Jie Lai;Wan Chen Sun;Guo Liang Li;Man Zhi Tan;Shi Bao Chen;骏 李;Hui Li Dou

Neiranji Gongcheng/Chinese Internal Combustion Engine Engineering

2012-12

The effects of the mass ratio of injected liquefied petroleum gas (LPG) to methanol and the LPG injection timing delay relative to the methanol injection timing on the formaldehyde and the unburned methanol emissions of a methanol blended with LPG engine during cold start were experimentally investigated using the single-cycle methanol injection strategy on an engine with fuel injection spark-ignition controlled electronically. The LPG offers only a function of supplementing start in methanol blended with LPG engines. The results show that the increase of the mass ratio of injected LPG to methanol improved firing performance of the methanol blended with LPG engine and reduced the unburned methanol emission. Optimal control of the LPG injection timing delay improved firing performance and reduced the unburned methanol emission significantly, and increased the formaldehyde emission slightly. At 276° of the LPG injection timing delay, the maximum pressure in cylinder reached 4.46 MPa and the unburned methanol emission decreased to 1173 × 10^-6. The emissions of formaldehyde and unburned methanol of the methanol blended with LPG engine during cold start varied inversely with the mass ratio of injected LPG to methanol and the LPG injection timing delay.

Changming Gong;骏 李;Xiumin Yu;Zhong Wang;Xunjun Liu

Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University

2010-5