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Presently, urban transportation highly depends on the fossil fuels, but its rapid fluctuating economic issues and environmental consequences impose the variegation of energy sources. Hydrogen enriched compressed natural gas (HCNG) engines offer the potential of higher brake thermal efficiency with low emissions, which also satisfies the strict pollutant emission standards. The two-zone turbulent entrainment quasi-dimensional combustion model is developed to predict the combustion process of spark-ignited hydrogen enriched compressed natural gas-fueled engines. The fundamentals of thermodynamic process, turbulent flame propagation model and other sub-models like laminar burning velocity, adiabatic temperature and ignition lag model are introduced for the better accuracy. The experiments have been conducted for three different fuels; pure CNG, 20% HCNG, and 40% HCNG blends under MAP of 105 kPa for various excess air ratios (λ) and ignition timing (θi).

At first, the dynamic electromagnetic characteristics of a pulsed solenoid valve is analyzed by experiments. The fast valve response is obtained by material modifications. Then, the intelligent solenoid driving method is discussed. The new techniques of the “active” PWM and the “d2i/dt2” detection are developed for feedback control of the solenoid holding current and the valve closure timing. Finally, the control and diagnosis method for the valve closure duration is investigated. A sensing mechanism utilizing momentary camshaft speed fluctuations of fuel injection pump is presented, which provides the basis for feedback control and diagnosis of the valve closure duration and diesel fuel injection process.

This paper presents an investigation of drivability issue of engine start-stop. Hybrid vehicles provide excellent benefits regarding fuel efficiency and emission. However, vibration results from constant engine start and stop events generate drivability issues, thus compromising driving comfort. This paper has designed a high speed torque sensor to capture instantaneous torque at the engine shaft. Its consequences help to find out the most suitable index of vibration severity. This paper is organized in four sections. The first section introduces the powertrain to be studied. The second section introduces development of a specially designed torque sensor. The torque sensor is installed between the engine and ISG (Integrated Starter Generator), alongside with an encoder. The torque sensor is utilized to collect the instantaneous shaft torque on occasion of engine start. In the third section, this paper has performed two experiments.

Based on the simulation results of tire rolling over perpendicular cleats by MPTM model, in present paper, a series of simulation results of tire rolling over oblique cleats with different angles are given. For that, the Modal Parameter Tire Camber property Model is established. For the appraisement of comparison between simulation and experimental results a problem concern the validation test is pointed out. In the end, simulation results of tire rolling over a series of continuous cleats are given.

Gasoline direct injection (GDI) engine technology is now widely used due to its high fuel efficiency and low CO2 emissions. However, particulate emissions pose one challenge to GDI technology, particularly in the presence of fuel injector deposits. In this paper, a 4-cylinder turbocharged GDI engine in the Chinese market was selected and operated at 2000rpm and 3bar BMEP condition for 55 hours to accumulate injector deposits. The engine spark timing, cylinder pressure, combustion duration, brake specific fuel consumption (BSFC), gaseous pollutants which include total hydro carbon (THC), NOx (NO and NO2) and carbon dioxide (CO), and particulate emissions were measured before and after the injector fouling test at eight different operating conditions. Test results indicated that mild injector fouling can result in an effect on engine combustion and emissions despite a small change in injector flow rate and pulse width.

Gasoline Direct Injection (GDI) engines have developed rapidly in recent years driven by fuel efficiency and consumption requirements, but face challenges such as injector deposits and particulate emissions compared to Port Fuel Injection (PFI) engines. While the mechanisms of GDI injector deposits formation and that of particulate emissions have been respectively revealed well, the impact of GDI injector deposits and their relation to particulate emissions have not yet been understood very well through systematic approach to investigate vehicle emissions together with injector spray analysis. In this paper, an experimental study was conducted on a GDI vehicle produced by a Chinese Original Equipment Manufacturer (OEM) and an optical spray test bench to determine the impact of injector deposits on spray and particulate emissions.

A tire force estimation algorithm is proposed for vehicle dynamic stability control (DSC) system to protect the vehicle from deviation of the normal dynamics attitude and to realize the improved dynamics stability in limited driving conditions. The developed algorithm is based on the theoretical analysis of all the subsystems of the active brake control in DSC system and modulation in DSC, and the robustness is achieved by a compensation method using nonlinear filter in the real time control. The software-in-loop simulation using Matlab/AMEsim and the ground test in the real car show the validation of this method.

This paper presents a two-layer torque vectoring control strategy for the Formula SAE racing car of Tsinghua University to enhance steering response, lateral stability and track performance. Firstly, the dynamic model of the existing FSAE car is built as parameters of tires, suspensions, motors and aerodynamics are measured and identified. Secondly, this paper develops a two-layer torque vectoring strategy, the upper-layer direct yaw moment (DYC) controller and the lower-layer torque distribution controller are developed in Simulink. The upper-layer sliding mode control DYC controller calculates the target additional yaw moment according to the target yaw rate based on the two-degree-of-freedom (2DOF) reference model, and the sideslip angle is constrained as well.

Lane changing is an essential action in commercial vehicles to prevent collisions. However, steering system malfunctions significantly escalate the risk of head-on collisions. With the advancement of intelligent chassis control technologies, some autonomous commercial vehicles are now equipped with a four-wheel independent braking system. This article develops a lane-changing control strategy during steering failures using torque vectoring through brake allocation. The boundaries of lane-changing capabilities under different speeds via brake allocation are also investigated, offering valuable insights for driving safety during emergency evasions when the steering system fails. Firstly, a dual-track vehicle dynamics model is established, considering the non-linearity of the tires. A quintic polynomial approach is employed for lane-changing trajectory planning. Secondly, a hierarchical controller is designed.

It is very significant for autonomous vehicles to have the ability to operate beyond the stable handling limits, which plays a vital role in vehicles’ active safety and enhances riding and driving pleasure. For traditional vehicles, it is rather difficult to control the longitudinal speed, sideslip angle and yaw rate simultaneously when drifting along a given trajectory because they are under-actuated. Nevertheless, for a 4-wheel-independent-drive (4WID) vehicle, it is possible and controllable thanks to its over-actuated characteristics. This article designs a trajectory following control strategy for automated drifting of 4WID vehicles. First, a double-track 7 degree of freedom (7DOF) vehicle dynamic model is established, which incorporates longitudinal and lateral load transfer and considers nonlinear tire models. The controller which proposes a hierarchical architecture is then designed.

The effects of different biodiesel blends on engine-out emissions under various transient conditions were investigated in this study using fast response diagnostic equipment. The experimental work was conducted on a modern 3.0 L, V6 high pressure common rail diesel engine fuelled with mineral diesel (B0) and three different blends of rapeseed methyl esters (RME) (B30, B60, B100 by volume) without any modifications of engine parameters. DMS500, Fast FID and Fast CLD were used to measure particulate matter (PM), total hydrocarbon (THC) and nitrogen monoxide (NO) respectively. The tests were conducted during a 12 seconds period with two tests in which load and speed were changed simultaneously and one test with only load changing. The results show that as biodiesel blend ratio increased, total particle number (PN) and THC were decreased whereas NO was increased for all the three transient conditions.

Combustion visualizations were carried out in a constant volume vessel to study the partially premixed combustion of a gasoline-like fuel using high speed imaging. The test fuel (G80H20) is composed by volume 80% commercial gasoline and 20% n-heptane. The effects of ambient gas composition, ambient temperature and injection pressure on G80H20 combustion characteristics were analyzed. Meanwhile, a comparison of the EGR effect on combustion process between G80H20 and diesel was made. Four ambient gas conditions that represent the in-cylinder gas compositions of a heavy-duty diesel engine with EGR ratios of 0%, 20%, 40% and 60% were used to simulate EGR conditions. Variables also include two ambient temperature (910K and 870K) and two injection pressure (20 MPa and 50 MPa) conditions.