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Reported in the current paper is a study of the effects of Nitric Oxide (NO) within a simulated Exhaust Gas Residual (sEGR) on Spark Ignition (SI) engine end gas autoignition. A modified version of the single cylinder Leeds University Ported Optical Engine Version 2 (LUPOE-2) engine was designed to completely eliminate retained residual gas and so allow unambiguous definition of the composition of the in-cylinder charge. The engine was alternately operated on stoichiometric mixtures of iso-octane, two Primary Reference Fuels (PRF), a Toluene Reference Fuel (TRF), and a commercially available Unleaded Gasoline (ULG) and air. These mixtures were diluted with sEGR (products of the complete stoichiometric combustion of the given fuel/air mixture) in mass fractions ranging from 0-15%; with and without 5000ppm NO (0.52% by mass) within that sEGR.

The paper discusses the concept, design and final results from the ‘Ultra Boost for Economy’ collaborative project, which was part-funded by the Technology Strategy Board, the UK's innovation agency. The project comprised industry- and academia-wide expertise to demonstrate that it is possible to reduce engine capacity by 60% and still achieve the torque curve of a modern, large-capacity naturally-aspirated engine, while encompassing the attributes necessary to employ such a concept in premium vehicles. In addition to achieving the torque curve of the Jaguar Land Rover naturally-aspirated 5.0 litre V8 engine (which included generating 25 bar BMEP at 1000 rpm), the main project target was to show that such a downsized engine could, in itself, provide a major proportion of a route towards a 35% reduction in vehicle tailpipe CO2 on the New European Drive Cycle, together with some vehicle-based modifications and the assumption of stop-start technology being used instead of hybridization.

A Gas to liquid (GTL) fuel was investigated for its combustion and emission performance in an IVECO EURO5 DI diesel engine with a DOC (Diesel Oxidation Catalyst) and DPF (Diesel Particle Filter) installed. The composition of the GTL fuel was analyzed by GC-MS (gas chromatography-mass spectrometry) and showed the carbon distribution of 8-20. Selected physical properties such as density and distillation were measured. The GTL fuel was blended with standard fossil diesel fuel by ratios of diesel/GTL: 100/0, 70/30, 50/50, 30/70 and 0/100. The engine was equipped with a pressure transducer and crank angle encoder in one of its cylinders. The properties of ignition delay and maximum in-cylinder pressure were studied as a function of fraction of the GTL fuel. Particle emissions were measured using DMS500 particle size instrument at both upstream (engine out) and downstream of the DPF (DPF out) for particle number concentrations and size distribution from 5 nm to 1000 nm.

As a new type of energy, free-piston linear generator (FPLG) attracts more research on its stable operation and power performance, while less on its combustion and emission performance. So, in this paper, the emission characteristics of FPLG in two different modes are studied through a port fuel injection (PFI) mode which was verified by the experiment and a gasoline direct injection (GDI) mode. The results showed that: both the GDI mode and the PFI mode produced large amounts of nitrogen oxide (NOx) during the working process. But the GDI mode produced before the PFI mode and it produced nearly 2 times than the PFI mode. However, the formation rate of NOx in GDI mode is much lower than that in PFI mode. Meanwhile, in both modes, 90% of NOX was generated in the cylinder at the temperature higher than 1750K, and only about 10% of NOX was generated at a temperature lower than 1750K.

The deformation of injector components cannot be disregarded as the pressure of the system increases. Deformation directly affects the characteristics of needle movement and injection quantity. In this study, structural deformation of the nozzle, the needle and the control plunger under different pressures is calculated by a simulation model. The value of the deformation of injector components is calculated and the maximum deformation location is also determined. Furthermore, the calculated results indicates that the deformation of the control plunger increases the control chamber volume and the cross-section area between the needle and the needle seat. A MATLAB model is established to The influence of structural deformation on needle movement characteristics and injection quantity is investigate by a numerical model. The results show that the characteristic points of needle movement are delayed and injection quantity increases due to the deformation.

In order to improve the anti-disturbance performance of engine-load and the effect on speed control for the diesel engine, the paper presents the fuzzy-PID speed control strategy in the architecture of torque-based control. The engine-load estimation algorithm is designed based on the mean-value-model and crankshaft dynamics model, and the estimation precision is validated by engine test in both steady and dynamic conditions. Through the experiment verification of the diesel engine, the fuzzy-PID control strategy based on load estimation can significantly improve the anti-disturbance performance of engine-load in the speed control.

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.

An opposed piston two-stroke engine is more suitable for use in an unmanned aerial vehicle because of its small size, excellent self-balancing, stable operation, and low noise. Consequently, in this study, based on experimental data for a prototype opposed piston two-stroke engine, numerical simulation models were established using GT-POWER for 1D simulation and AVL-FIRE for 3D CFD simulation. The mesh grid and solver parameters for the numerical model of the CFD simulation were determined to guarantee the accuracy of the numerical simulation, before studying and optimizing the ventilation efficiency of the engine with different dip angles. Furthermore, the fuel spray and combustion were analyzed and optimized in details.

Incomplete-combustion and misfire are the hurdles in internal combustion engines to run on ultra-lean mixture, whereas high thermal efficiency has been achieved at lean mixture. The burning characteristics of n-heptane with 0% and 30% hydrogen additions were studied at 393K-453K and 100kPa-300kPa up to near lean burn limits, λ=0.8-2.0. The flame appeared in spherical shape only by 37-mJ ignition energy (IE) at λ=0.8-1.5, while further lean mixture, ≥1.6, could be ignited only by 3000-mJ with the distorted flame shape. The flame buoyed in the mixture when burning velocity calculated by kinetic mechanism was equal or less than 19.83 cm/s at the initial conditions of λ=1.8, 393K and 100kPa. The thermal instability under impact of initial pressure and temperature was higher at lean mixture than at stoichiometric mixture.

Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation.

Hydrogen fuel is a future energy to solve the problems of energy crisis and environmental pollution. Hydrogen internal combustion engines can combine the advantage of hydrogen without carbon pollution and the main basic structure of the traditional engines. However, the power of the port fuel injection hydrogen engines is smaller than the same volume gasoline engine because the hydrogen occupies the volume of the cylinder and reduces the air mass flow. The turbocharger can increase the power of hydrogen engines but also increase the NOx emission. Hence, a comprehensive controlling strategy to solve the contradiction of the power, BTE and NOx emission is important to improve the performance of hydrogen engines. This paper shows the controlling strategy for a four-stroke, 2.3L hydrogen engine with a turbocharger. The controlling strategy divides the operating conditions of the hydrogen engine into six parts according to the engine speeds and loads.

Heat Release Rate (HRR) analysis is indispensable in engine research. The HRR of Internal Combustion Engines (ICEs) is most sensitive to gamma (γ). The proposed HRR models in literature were largely based on γ expressed as functions of temperature. However, γ is depended on temperature as well as the excess air ratio (λ). In this work, an improved HRR model based on γ(T, λ) was used to investigate the combustion behaviour of standard diesel, Gas-to-Liquid (GTL) diesel and Hydrotreated Vegetable Oil (HVO) diesel in a 96 kW, multiple fuel injection, Euro V, Direct Injection (DI) engine. The improved HRR model (Leeds HRR model) was validated for the alternative fuels by comparing the fuel masses predicted by the model to the measured fuel masses. The fuel masses predicted by the Leeds HRR model were also compared to the predictions from four HRR models that were based on γ(T).

Hydrodynamic torque converter parameter integrated optimization design system is established based on tri-dimensional flow field theory. Design segments such as optimization initial values searching by meanline theory, cascade solid modeling, structure mesh of flow passage, CFD(computational fluid dynamics), DOE(design of experiment), RSM(response surface model)and optimization algorithm are integrated in this system and therefore a three dimensional optimization design method for hydrodynamic torque converter is presented and realized. An optimization design instance is accomplished by workstation computer cluster, and its result shows that speed and accuracy of design are improved and design system based on 3D flow field theory is accurate and effective.

Performances of a centrifugal turbocharger compressor are investigated and validated in this paper. Based on the validation results, numerical optimizations are performed using ANN and CFD methods. Different impeller geometry with free parameters controlling stacking laws, end-wall, blade sectional camber curves and corresponding performances are used as input layer of ANN in the optimization, while adiabatic total-to-total efficiency and total pressure ratio are used as output layer of the optimization cycle. With this method, the performances of the compressor investigated in this paper are improved notably.

This present paper described an experimental study on the combustion and emission characteristics of a diesel engine at idle at different altitudes. Five altitudes ranging from 550m to up to 4500m were investigated. Combustion parameters including in-cylinder pressure and temperature, heat release, fuel mass burning and so forth, together with emission factors including CO, HC, NOx and PM were tested and analyzed. The result of on-board measurement manifested that in-cylinder pressure descended consistently with the rising of altitude, while both the maximum in-cylinder temperature and exhaust temperature ascended with the altitude. It was found that ignition delay was lengthened at higher altitude, but the combustion duration became shorter. The crank angle towards 90% fuel burnt has hardly changed with the variation of altitude. As for heat release, the difference of slopes observed at different altitudes was quite slight.

In order to improve energy supply diversity and reduce carbon dioxide emissions, sustainable bio-fuels are strongly supported by EU and other governments in the world. While the feedstock of biofuels has caused a debate on the issue of sustainability, the used cooking oil (UCO) has become a preferred feedstock for biodiesel manufacturers. However, intensive energy consumption in the trans-esterification process during the UCO biodiesel production has significantly compromised the carbon reduction potentials and increased the cost of the UCO biodiesel. Moreover, the yield of biodiesel is only ∼90% and the remaining ∼10% feedstock is wasted as by-product glycerol. Direct use of UCO in diesel engines is a way to maximize its carbon saving potentials.

Persisting concerns regarding ride comfort, directional stability and more recently road damage have caused the manufacturers of commercial vehicles to consider controllable suspension systems. An electronically controllable adaptive suspension that comprises a variable spring rate system, switchable damping and load levelling is proposed as a cost-effective solution. This paper describes the aforementioned system and provides an outline of the design scheme for a prototype system; practical issues such as system configuration/detail, control system requirements, etc., are discussed. The system is evaluated analytically and both ride and handling modes are examined. In conclusion, performance capabilities are defined and cost-benefit issues addressed.

In order to improve the tractive ability, steering capability and directional stability, etc. of automated mechanical transmission (AMT) vehicles running on the wet and slippery road, the anti-slip regulation (ASR) technologies for AMT vehicles are developed. The significance of ASR for AMT vehicles is introduced; a road friction recognition method based on the deceleration of driving wheels is investigated; a fuzzy anti-slip control system based on adjustment of engine torque is developed and the corresponding experimental verification is conducted. The experimental results denote that the proposed method is effective to eliminate the excessive slip when the AMT vehicle travels on the low friction road.

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.

Based on BF6M1015CP electronic diesel engine (it is a supercharged, water-cooled engine. It has 6 cylinders and it is for heavy-duty vehicle) and HD4070PR electronic automatic transmission (it covers heavy-duty applications requiring high input horsepower and torque. It contains torque converter module, control module, planetary module and output module. It has 7 forward gears and a power-take -off (PTO) and a retarder), the paper analyzes the shift system of an electronic automatic transmission and sets up a mathematic module of the shifting process. With the model the shifting process is analyzed and the model can be used directly in shifting process control, and the rules of shifting process can be derived. To improve the shift quality, in the paper the different control methods in different phases are used and reviewed that Include the open-loop control, fixed ramp rate, and closed-loop control.