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The acquisition of more authentic cylinder pressure data is the basis of engine combustion analysis. Due to the multiple advantages, quartz piezoelectric pressure transducers are generally applied to the measurement of the cylinder pressure. However, these transducers can only produce dynamic cylinder pressure data which may be significantly different from the actual values. Thus, the cylinder pressure data need to be corrected through a certain method, while different cylinder pressure correction methods will cause result divergences of the combustion analysis. This paper aims to acquire a proper cylinder pressure correction method by carrying out theoretical analysis based on the polytropic process in the compression stroke as well as the experimental research of the cylinder pressure of a turbocharged eight-cylinder diesel engine.

Within the hydraulic shifting circuit of power-shift steering transmission, the performance of filter is generally characterized by the theoretical filtration ratio. However in practical work, the actual filtration ratio is far less than the theoretical ratio. On the basis of investigation on the structural characteristics, the oil flowing distribution and the filter mechanisms, the re-filtering rate ω and recontaminative rate θ are defined to simulate the actual filtering process. Therefore, the dynamic filtration ratio is modelled and simulated in MATLAB/Simulink to investigate that how the filtering rate ω and θ influence the dynamic filtration ratio and the deviation between the dynamic ratio and theoretical ratio. Afterwards, the variation of dynamic filtration ratio is tested through a filtration experiment under the circumstances of various flow rate, temperature and pressure.

Hydrogen is a promising energy carrier because it is characterized by a fast combustion velocity, a wide range of sources, and clean combustion products. A hydrogen internal combustion engine (H2ICE) with a turbocharger has been used to solve the contradiction of power density and control NOx. However, the selection of a H2ICE compressor with a turbocharger is very different from traditional engines because of gas fuel. Hydrogen as a gas fuel has the same volume as its cylinder and thus increases pressure and reduces the mass flow rate of air in cylinder for a port fuel injection-H2ICE (PFI-H2ICE). In this study, a general method involving a H2ICE with a turbocharger is proposed by considering the effect of hydrogen on cylinders. Using this method, we can calculate the turbocharged pressure ratio and mass flow rate of air based on the target power and general parameters. This method also provides a series of intake temperatures of air before calculation to improve accuracy.

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.

With the development of advanced ABE fermentation technology, the volumetric percentage of acetone, butanol and ethanol in the bio-solvents can be precisely controlled. To seek for an optimized volumetric ratio for ABE-diesel blends, the previous work in our team has experimentally investigated and analyzed the combustion features of ABE-diesel blends with different volumetric ratio (A: B: E: 6:3:1; 3:6:1; 0:10:0, vol. %) in a constant volume chamber. It was found that an increased amount of acetone would lead to a significant advancement of combustion phasing whereas butanol would compensate the advancing effect. Both spray dynamic and chemistry reaction dynamic are of great importance in explaining the unique combustion characteristic of ABE-diesel blend. In this study, a semi-detailed chemical mechanism is constructed and used to model ABE-diesel spray combustion in a constant volume chamber.

In order to meet the need of high pressure common rail diesel engine, calibration for injection quantity and basic MAP of electronic-controlled injector are made. Combining with testing data, influencing factors for consistency and identity of injecting fuel in electronic-controlled injector are analyzed, in the condition of small quantity, controlled-pressure undulation quantity and injecting pulse revising are presented to achieve the respective demand. Primary basic map for common rail pressure and injecting fuel are fixed with alterable step method, and calibration of fuel quantity MAP is made on bench test. Finally test of electronic-controlled injector equipped in diesel engine is finished, testing result showed that calibration process and method are reasonable.

NOx are the only harmful emissions of hydrogen internal combustion engine. EGR is one of the effective methods to reduce NOx. The traditional EGR is not suitable for hydrogen internal combustion engine. Therefore, the study of influence of hot EGR on hydrogen internal combustion engine is important. A 2.0L hydrogen internal combustion engine with hot EGR system model is employed to optimize the diameter and position of hot EGR based on a simulation analysis. The result shows that both of the combustion temperature and NOx increase as EGR increases due to the rise of intake temperature for low load condition, for heavy load, with the increase of EGR rate, NOx emissions decreases slightly before the mixture equivalence ratio comes to 1and then dropped significantly after the mixture equivalence ratio greater than 1. Unburned hydrogen in TWC has the effect of reducing NOx after catalysts decrease largely.

Nowadays, the world is facing severe energy crisis and environment problems. Development of hydrogen fuel vehicles is one of the best ways to solve these problems. Due to the difficulties of infrastructures, such as the hydrogen transport and storage, hydrogen fuel vehicles have not been widely used yet. As a result, Hydrogen-gasoline dual-fuel vehicle is a solution as a compromise. In this paper, three way catalytic converter (TWC) was used to reduce emissions of hydrogen-gasoline dual-fuel vehicles. On wide open throttle and load characteristics, the conversion efficiency of TWC in gasoline engine was measured. Then the TWC was connected to a hydrogen internal combustion engine. After switching the hydrogen and gasoline working mode, emission data was measured. Experiment results show that the efficiency of a traditional TWC can be maintained above 85%., while it works in a hydrogen-gasoline dual-fuel alternative working mode.

The low cycle fatigue experiment is extensively used to test the reliability and durability of turbocharger. Low cycle fatigue test is mainly the switching between high and low speed. As the result of the experiment, the fatigue life is shorter as the difference between high and low speed becomes greater. In the traditional low cycle fatigue test, a large air compressor is needed to drive the turbocharger under different operating conditions, which consume large amounts of electric power. This paper presents a new experiment device which has double chambers and double turbochargers. This device can be self-circulating, without the large air compressor, to realize high and low speed switching on the premise of not exceeding the limitation of turbine entry temperature. First, a detailed model is established in GT-Power and self-circulation test data has been used to validate the model.

This paper describes a uniform Hardware-In-the-Loop (HiL) test rig for the different types of Electronic Braking System (EBS). It is applied to both modular testing and integrated testing. This test rig includes a vehicle dynamic model, a real-time simulation platform, an actual brake circuit and the EBS system under test. Firstly, the vehicle dynamic model is a highly parameterized commercial vehicle model. So it can simulate different types of commercial vehicle by different parameter configurations. Secondly, multi-types of brake circuit are modeled using brake components simulation library. So, it can test the EBS control unit independently without the influence of any real electro-pneumatic components. And a software EBS controller is also modeled. So it can test the algorithm of EBS offline. Thirdly, all real electro-pneumatic components without real gas inputted are connected to the real-time test platform through independent program-controlled relay-switches.

When the EFI system is used in a specific engine, lots of experiments are needed to optimize the control data (MAP). This work is time and financial consuming. This paper aims to develop a computer-based simulation and test system, which can produce the initial control MAP with good accuracy, and calibrate the ECU on-line. So the experiments are reduced and calibration is accelerated. In order to improve the accuracy of the initial control data, the mathematical models are built not only based on theoretical equations, but also on the control data of typical operation points, which is obtained by the on- line calibration of specific engines. This system can also perform some special calibrations, like "constant pulse width" and "square wave modulation."

Turbocharged and intercooled DI engines, fueled with different blends of biodiesel and diesel fuel, were chosen to conduct performance and emission tests on dynamometers. The properties of the test fuels were tested. The cylinder pressure and fuel injection pressure signals were recorded and combustion analysis was conducted. The engine exhaust emissions were measured. The results of the study indicated that HC, CO, PM and smoke emissions improvement was obtained. But there was an increase in fuel consumption and NOx emission, and a slight drop in power with the blends. The combustion analysis showed that biodiesel had a shorter ignition delay and a lower premixed combustion amount, but had an early start of injection caused by the fuel properties. The relationship between combustion and emissions was discussed.

In order to achieve simultaneous removal of particulate matters (PM) and NOX in diesel exhaust, a new kind of aftertreatment prototype has been developed. The prototype combined effects of static, cyclone, non-thermal plasma and hydrocarbon selective catalytic reduction. Experiments have been carried out with standard gases simulating diesel exhaust. Physical and chemical effects that took place in the prototype are as follows: the collection of PM by electrostatic-cyclone system, the oxidative combustion of PM, the selective catalytic reduction of NOX, and the reaction between PM and NOX. The effect of non-thermal plasma makes the density of NO decrease and that of NO2 increase, whereas, the amount of NOX remains the same. Employing catalyst coupled with non-thermal plasma debase the temperature by about 50◻, there the peak value of transform rate appears.

Dual-fuel combustion combining a premixed charge of compressed natural gas (CNG) and a pilot injection of diesel fuel offer the potential to reduce diesel fuel consumption and drastically reduce soot emissions. In this study, dual-fuel combustion using methane ignited with a pilot injection of No. 2 diesel fuel, was studied in a single cylinder diesel engine with optical access. Experiments were performed at a CNG substitution rate of 70% CNG (based on energy) over a wide range of equivalence ratios of the premixed charge, as well as different diesel injection strategies (single and double injection). A color high-speed camera was used in order to identify and distinguish between lean-premixed methane combustion and diffusion combustion in dual-fuel combustion. The effect of multiple diesel injections is also investigated optically as a means to enhance flame propagation towards the center of the combustion chamber.

The combustion characteristics of gasoline-diesel dual-fuel in an electronic-controlled high pressure common rail optical engine were investigated under different diesel injection timings and gasoline/diesel ratios by a high-speed photography method. The experimental results show that the dual-fuel combustion process is influenced by diesel combustion and gasoline homogenous combustion, respectively, with bright yellow flames and blue flames observed in the combustion chamber. At a gasoline/diesel ratio of 0.91, the injection timing affects the ignition timing and combustion modes significantly. When the diesel injection timing is before −25° after top dead center (ATDC), advancing the injection timing tends to prolong the ignition delay and the gasoline-diesel dual-fuel combustion is similar to the pre-mixed charge compression ignition (PCCI) combustion with a rapid single-stage heat release.

A single-cylinder Gasoline Direct Injection Engine (GDI) engine with a centrally mounted spray-guided injection system (150 bar fuel pressure) has been operated with stoichiometric and rich mixtures. The base fuel was 65% iso-octane and 35% toluene; hydrogen was aspirated into a plenum in the induction system, and its equivalence ratios were set to 0, 0.02, 0.05 and 0.1. Ignition timing sweeps were conducted for each operating point. Combustion was speeded up by adding hydrogen as expected. In consequence the MBT ignition advance was reduced, as were cycle-by-cycle variations in combustion. Adding hydrogen led to the expected reduction in IMEP as the engine was operated at a fixed manifold absolute pressure (MAP). An engine model has also been set up using WAVE. Particulate Matter (PM) emissions were measured with a Cambustion DMS500 particle sizer.

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.

A boost system with an auxiliary gas turbine used to recover diesel engine power at plateau conditions is proposed. System matching calculation, preliminary design, and performance simulation of the compressor with double parameter output are presented, as well as the preliminary design, flow simulation, and combustion process of the combustion chamber. Results show that the new system has better recovery performance and higher fuel economy potential than the simple charging scheme. For future research work, possible improvements and development direction are recommended.

This paper first discusses the principles of how to identify whether a time series has chaotic characteristics, and explores a method of finding out the embedding dimension of a time series. Then Grassberger-Procaccia (G-P) algorithm is adopted to calculate correlative dimension. After the validity of G-P algorithm is confirmed using several traditional strange attractors, it is applied to calculate the fractal dimension of some vibration signals of an automotive transmission. This article presents how to apply chaos and fractal theories to diagnose the wearing of ball bearings in automotive transmissions based on the analysis of the transmission acceleration vibration signals. The results show that the vibration signals of automotive transmissions have fractal nature. There are certain correlations between a bearing's condition and the fractal dimension of its vibration signal.

The combustion characteristics of hydrogen-air mixtures have significance significant impact on the performance and control of hydrogen-fueled internal combustion engines and the combustion velocity is an important parameter in characterizing the combustion characteristics of the mixture. A four-cylinder hydrogen internal combustion engine was used to study hydrogen combustion; the combustion characteristics of a hydrogen mixture were experimentally studied in a constant-volume incendiary bomb, and the turbulent premixed combustion characteristics of hydrogen were calculated and analyzed. Turbulent hydrogen combustion comes under the folded laminar flame model. The turbulent combustion velocity in lean hydrogen combustion is related not only to the turbulent velocity and the laminar burning velocity, but also to the additional turbulence term caused by the instability of the flame.