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Butanol is deemed as a potential alternative fuel for vehicle, but there are few studies about applying butanol in engine combustion. This paper focuses on application of butanol-gasoline blend fuel on scooter engine. In this research, different volume percentage of butanol-gasoline blend fuel, B10, B20, B40, B60, B80 and B100 are applied on 125cc scooter engine to conduct engine experiment, and higher than B60 blend fuel is declared as high butanol concentration blend fuel. The test conditions are set at 4000 and 6000rpm under partial load and full load. After executing engine experiment, engine performance, brake specific fuel consumption (BSFC), emissions and combustion analysis are discussed. Furthermore, viscosity and fuel spray are tested with high butanol concentration blend fuel. The engine experimental result shows that B100 fuels can increase engine performance under engine 4000 and 6000rpm.

Fuel film dynamics in the intake manifold are considered to develop air fuel ratio (AFR) control strategy with on-line system identification for a V2 engine in this paper. A1000 cc four-stroke two-cylinder, water-cooled port injection SI engine is used as the target engine to develop the engine model in Matlab/Simulink. The model which consists of charging, fueling, combustion, friction, and engine rotational dynamics is used to verify the proposed AFR control. Since the fuel film dynamics changes with different engine operating conditions, the fuel film parameters are often listed as look-up tables for fuel film dynamics calculation in the conventional AFR control. However, those parameters might be inaccurate during transient engine operation. Different intake port temperature will affect the accuracy of those fuel film parameters as well. In order to solve this problem, recursive least square (RLS) is used to identify those parameters on-line.

This paper develops an engine model for the model-in-the-loop (MIL) and hardware-in-the-loop (HIL) application to shorten the time duration and reduce the costs of developing and verifying the engine management system (EMS). The target engine is a 1.0L V-type two cylinder water-cooled spark-ignition engine. The engine model is developed using a so-called modulization method, which includes to: (1) separate the sub-models according to the different physical phenomena; (2) collect the sub-models to establish a library; (3) execute the component modules based on a pre-determined sequence by a more flexible way. The engine model is then applied in MIL structure for testing and verifying the control strategies in the developed EMS. After all strategies are verified, the HIL structure is constructed by a hardware controller and a virtual engine in the xPC target. The execution time-step of engine model is analyzed to keep enough accuracy and numeric stability for real-time simulation.

Engine control units manage various conditions in an operating engine, including fuel injection, spark ignition and valve timing, in order to achieve the goals of high performance, high fuel efficiency and low emissions. Typically, engine models are necessary for developing engine control systems. Most mean value engine models (MVEM) are based on empirical volumetric efficiency, which contributes to calculating intake air flow rate. Therefore, they are not capable of simulating changes in valve lift and valve timing, and cannot be used for a variable valve train (VVT) engine. A method of calculating intake air flow rate with variable valve lift and valve timing is needed to adapt to the demands on VVT engine models. An engine model is proposed that focuses on a charging model, developed by using a filling-and-emptying model to simulate the air exchange in an engine, including intake- and exhaust-air flows.

The phenomenon of fuel-film dynamics for four-stroke small-scale spark-ignition engines is investigated in this paper. A first-order fuel-film model, so-called tau-x model, is used to represent the fuel dynamics. The parameters of fuel-film model, which consists of the portion of fuel that deposited on the manifold wall and the time constant of the fuel evaporation process, are identified using the recursive least squared technique. Performances of the proposed algorithm are evaluated using a nonlinear engine model in Matlab/Simulink. The preliminary simulation results show that the proposed algorithm can accurately be used to identify the parameters of fuel-film model. The experimental data are then utilized to study the characteristics of fuel-film dynamics, and show that the fuel-film dynamics is significantly affected by engine speed, throttle opening, injection timing, and intake temperature.

This paper constructed a parallel type hybrid-electric bus model based on GM-Allison system which is consisted of three planetary gear-sets and two motors. The simulation model is modified from the backward-looking simulation of ADVISOR. The hybrid-electric bus (HEB) is simulated to compare with a conventional diesel bus. Four different driving cycles are employed: Taipei City Bus Cycle, New York Bus Cycle, Manhattan Cycle, and Central Business District Cycle. Three different control strategies, namely speed control, torque control, and power control are studied. The simulation results show that the GM-Allison hybrid-electric bus with good control strategy can improve fuel economy by 66% compared to a conventional diesel bus. As for exhaust emissions, CO, HC, NOx and PM are reduced by 83%, 59%, 66% and 62%, respectively.

A heat transfer model for small-scale spark-ignition engines has been proposed by authors in previous study. However, this model is only based on single engine, it may not be suitable for the others. In order to improve the accuracy of predicted heat transfer rate for different small-scale engines, another heat transfer model using Stanton number based on two engines is proposed. Prediction results of instantaneous heat flux and global heat transfer based on the proposed model are compared with the experimental results and prediction results of previous model. It is found that the proposed model has prediction results closer to the measured data than the previous models.

Due to the nonlinear time-varying nature of the spark-ignition engine, an adaptive multi-input single-output (MISO) controller based on self-tuning regulator (STR) is proposed for idle speed control in this paper. The spark timing and idle air control are simultaneously employed as control inputs for maintaining the desired idle speed, and are designed based on P and PI type STR, respectively. The Recursive Least Square technique is employed to identify the engine as a first-order MISO linear model. Pole placement technique is then used to design the adaptive MISO controller. Performances of the proposed algorithm are evaluated using a nonlinear engine model in Matlab/Simulink. The system parameters with 10% uncertainties are also utilized to perform the associated robustness analysis. Preliminary simulation results show significant reduction of speed deviations under the presence of torque disturbances and model uncertainties.

This work studies the potential to use nanoparticles as additives in lubrication oil to improve friction and wear properties. The friction coefficient, electrical contact resistance and wear depth are experimentally measuring using a reciprocating sliding tribo-tester at various temperatures, contact pressures and sliding velocities. The test results show that the nanoparticle as additive in base oil can reduce friction and wear by up to 50% in mixed and boundary regimes, but in a commercial engine oil, it has a relatively minor effect. The material properties, size and shape of nanoparticles affect their tribological properties. The mechanisms of friction and wear behavior improved are briefly discussed.

In order to reduce engine control strategy development time and cost, the Hardware-In-the-Loop (HIL) simulation technology is developed. This paper establishes a simulation model and control platform based on the HIL structure for studying control strategy development and verification. A 125c.c. engine model verified by the experimental data is established in Matlab/Simulink, which is used as a virtual engine and then implemented in the xPC real-time system. The Motorola MC 68376 controller chip provides control signals included injection duration/timing and ignition timing for the virtual engine. A PCI-6024E input/output board is used as an interface between the controller and the virtual engine. A simulation model, which consists of engine, powertrain, tire, and pitch plane dynamics, is used to evaluate the response of engine dynamics and longitudinal dynamics via HIL simulation.

In order to study the noise effect of the crank angle sensor on electronic fuel injection (EFI) control system, a Kalman filter with stroke identification is employed to estimate the crankshaft rotational dynamics. Estimated crank angle and speed are then used for EFI system. A 125 c.c. scooter engine verified by the experimental data is used to design the Kalman filter. A simulation model, which consists of nonlinear engine dynamics, powertrain dynamics, tire dynamics, and pitch-plane motorcycle dynamics, is established in Matlab/Simulink to evaluate the performance of the Kalman filter at various noise conditions.

A Hybrid Electric Motorcycle (HEM) with a variable-winding brushed DC wheel motor is proposed in this paper. When the windings are connected in parallel, the motor has wide speed range suitable for high-speed cruising. When the windings are connected in series, the motor can provide high starting torque and thus reduce the necessary engine size for the proposed HEM. The optimal upper and lower power limits of the engine operating region are obtained from the optimal design theory. A dynamic simulation model is established in Matlab/Simulink to evaluate the performance of the proposed HEM and traditional motorcycles using the ECE40 driving cycle.

A Hybrid Electric Motorcycle (HEM) with a direct-driven wheel motor is proposed in this paper. The rear wheel is driven by an internal combustion engine and a powertrain system of a traditional motorcycle with minor modifications. The front wheel is driven by a direct-driven wheel motor. The proposed HEM is a parallel configuration. Both wheels can supply tractive forces simultaneously to drive the motorcycle when necessary. A rule-based structure is used to design the power split controller of the proposed HEM. Fuel economy of the proposed design will be evaluated by a dynamic simulation model in Matlab/Simulink using ECE-R40 driving cycle.

For a conventional scooter engine, not only the crankshaft position estimation is insufficient based on the one-tooth crankshaft wheel, but also the speed measurement might be contaminated by sensor noise easily. The authors propose a technique using Kalman filter to estimate crankshaft position and engine speed for digital ignition control of a scooter engine. A 125cc engine model, which is verified by the experimental data of the target engine, will be used to design the Kalman filter. A simulation model, which consists of nonlinear engine dynamics, powertrain dynamics, tire dynamics, and pitch plane dynamics, is used to evaluate the performance of proposed estimation algorithm with different tooth numbers of crankshaft wheel and various noise conditions.

This paper presents the application of rapid prototyping electronic control unit (ECU) to fuel injection and ignition control of electronic fuel injection motorcycle engine by using Model-Based environment. As a scene on state of the art, it is famous accepted that the MATLAB Model-Based environment is an efficient development platform for engine management systems (EMS). These come from several benefits: (1) System level design environment, (2) Real-time simulation, and (3) Model to chip technology during rapid prototyping ECU development process. Therefore, this research uses these advantages to study the rapid prototyping controller (RPC) of a SI engine for decreasing time and cost requirements of development process. The target vehicle is a scooter with a four-stroke 125 cc. single cylinder engine.