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There are many methods developed over the past decade to solve the problem of energy management control for hybrid electric vehicles. A novel method is introduced in this paper to address the same problem which reduces the problem to a set of physical equations and maps. In simple terms, this method directly calculates the actual cost or savings in fuel energy from the generation or usage of electric energy. It also calculates the local optimum electric power that yields higher electric fuel savings (EFS) or lower electric fuel cost (EFC) in the fuel energy that is spent for driving the vehicle (which in general does not take the system to the lowest engine Brake Specific Fuel Consumption (BSFC)). Based on this approach, a control algorithm is developed which attempts to approach the global optimum over a drive cycle.

In diesel engine development, fuel consumption, emissions and combustion noise have been main development objectives for fuel economy, low emissions and NVH. These main objectives can be achieved with advanced engine technologies. As electronic actuating systems are widely applied on diesel engines, elaborate control is required. This is because the main development targets are greatly affected by engine control parameters but frequently have a trade-off relationship. Therefore, the optimization of combustion control parameters is one of the most challenging tasks for improvement. As an efficient method, the DOE methodology has been used in engine calibration. In order to develop a mathematical model, the input and output values must be measured. Unlike other variables, combustion noise has been continually reported to have better indication method in simplified way. In this paper, advanced noise index from cylinder pressure signal is applied on engine test.

This paper focuses on the vehicle test result of the US fuel economy test cycles such as FTP75, HWY and US06 with model based Cooled EGR system. Cooled EGR SW function was realized by Model Based Development (internal rapid prototyping) using iRPT tool. With EGR, mixing exhaust gas with clean air reduces the oxygen concentration in the cylinder charge, as a result, the combustion process is slowed, and the combustion temperature drops. This experiment confirmed that the spark timing was more advanced without knocking and manifold pressure was increased in all cases with EGR. A positive potential of fuel economy improvement on FTP mode, US06 mode have seen in this experiment but not for HWY where the engine load is quite low and the spark advance is already optimized. As a result, fuel economy was increased by maximum 3.3% on FTP, 2.7% on US06, decreased by 0.3% on HWY mode respectively with EGR.

To design an optimum engine intake system, a flow model for the intake manifold was developed by the method of characteristics. The flow in the intake manifold was one-dimensional, and finite difference equations were derived from the governing equations of flow. The thermodynamic properties inside a cylinder were found by the first law of thermodynamics, and the boundary conditions were formulated using a steady flow model. By comparing the calculated results with experimental data, the appropriate boundary conditions and convergence limits for a flow model were established. From this model, design variables for the intake system were investigated. The optimum manifold length became shorter when the engine speed were increased. The effect of intake valve timings on inlet air mass was also studied by this model. Advancing intake valve opening decreased inlet air mass slightly, and the optimum intake valve closing was found.

This paper discusses the effects of lubricant viscosity on the friction characteristics of engine bearing and cam/tappet which are the typical moving parts of an engine and operate in different lubrication regimes. Based on the measured crankshaft temperatures, we calculated the friction coefficient of the engine bearing according to Sommerfeld number by a simple heat equilibrium equation. The oil film thicknesses between cam and tappet were measured in a motored cylinder head which had a direct acting type overhead camshaft. The boundary and viscous friction components were estimated separately according to a parameter defined as the ratio of the central oil film thickness to the composite surface roughness. These two friction components were added to calculate the friction coefficient. Finally, the motoring friction torque was measured and compared with the estimated friction coefficient.

This paper presents a conditional misfire monitoring method to reduce the computing burden of the motoring. In this conditional monitoring method, the ECU performs misfire detection only when there is high probability of misfire events. The condition for performing the misfire detection is determined by the pre-index which is defined as the deviation of the segment durations of the crankshaft in this paper. The quantity of the code of calculating the pre-index is 7 times less than that of a conventional monitoring method so that the computing burden can be reduced with the conditional monitoring method. The experimental results shown that the pre-index and the conditional monitoring method are valid.

A throttle/brake control law for the intelligent cruise control (ICC) system has been proposed in this paper. The ICC system consists of a vehicle detection sensor, a controller and throttle/brake actuators. For the control of a throttle/brake system, we introduced a solenoid-valve-controlled electronic vacuum booster (EVB) and a step-motor-controlled throttle actuator. Nonlinear computer model for the electronic vacuum booster has been developed and the simulations were performed using a complete nonlinear vehicle model. The proposed control law in this paper consists of an algorithm that generates the desired acceleration/deceleration profile in an ICC situation, a throttle/brake switching logic and a throttle and brake control algorithm based on vehicle dynamics. The control performance has been investigated through computer simulations and experiments.

A GT-suite commercial code was used to develop a fully integrated model of a light duty commercial vehicle with a V6 diesel engine, to study the use of a BorgWarner dual mode coolant pump (DMCP) in active thermal management of the vehicle. An Urban Dynamometer Driving Schedule (UDDS) was used to validate the simulation results with the experimental data. The conventional mechanical pump from the validated model was then replaced with the dual mode coolant pump. The control algorithm for the pump was based on controlling the coolant temperature with pump speed. Maximum electrical speed of the pump and the efficiency of the pump were used to determine whether the pump should run in mechanical or electrical mode. The model with the dual mode coolant pump was simulated for the UDDS cycle to demonstrate the effectiveness of control strategy.

In this paper, an active type variable intake system is proposed, which improves both engine power and NVH performance. The proposed system uses a magnet valve to control the air path to the engine intake manifold. While other types of variable intake system such as vacuum actuator type or DC motor type need an ECU to control the valve, the proposed system only uses force equilibrium between magnetic force and vacuum pressure, resulting in weight and cost reduction. The system is composed of dual duct (duct A, duct B) and a magnet valve. In low RPM region, the magnet valve is closed and only duct A is used to supply air into the engine. In high RPM region the valve opens up and maximizes the amount of the air that goes into the engine intake manifold. The result is that the output power of the engine is maximized in high RPM region, as well as the NVH performance is improved in low RPM region.

The paper presents a thermal management development capability and approach that was put in place to understand the relative benefit of various thermal components, layouts and control strategies. The use of the approach on a modern diesel powered vehicle is given. Thermal performance along with associated fuel economy improvements are shown over various test cycles including the FTP and US06. Results are given for a GT-Suite simulation as well as on vehicle.

This study presents engine test results of HMC's piston-ported 2-stroke gasoline engine. This single cylinder engine of 400cc displacement has featured in direct injection(DI) of fuel and external blower scavenging of air. Two different concepts of DI system were adopted, one is high pressure fuel injection(HPFI) system for solid fuel only and the other is low pressure air-assisted fuel injection(AAFI) system. Two kinds of engines with different scavenging intake port shapes and areas were tested to find the effect of scavenging port type on engine performance. Also tested were trends of BSFC, BSHC and BSCO versus fuel injection timing and engine speed with HPFI and AAFI, respectively. Power and boost pressure at full load and BSFC and BSHC at part load were tested.

A 1-D GT-Power model based investigation has been carried out to identify the impact of late intake valve closing (LIVC) on fuel economy and emission reduction of a modern small bore diesel engine. The diesel engine examined employed a variable turbine geometry (VTG) turbocharger with air-to-air charge cooler, cooled low pressure exhaust gas re-circulation (LP-EGR), and cooled high pressure exhaust gas re-circulation (HP-EGR). The LIVC system investigated varied the closing time of the intake valve by increasing or decreasing the dwell at the maximum valve lift point. This paper describes how the fuel economy and NOx emission of the diesel engine were affected by varying the intake valve closing time. The intake valve closing time was delayed by as much as 60 degrees.

Trying to improve the modern diesel engine's NOx/soot tradeoff without giving up fuel economy continues to be a core target for the engine development community. One of the options not yet fully investigated for the diesel is applying variable valve events to the engine breathing process. Already used in some heavy-duty applications, late intake valve closing has long been regarded as a possible strategy for small diesel engines. Single-cylinder tests applying fully variable valve events have demonstrated potential but also raised doubts about VVA benefits on automotive size diesel engines. Full engine testing using realistic valve train technology is seen as key to judging its true performance because it covers not only combustion benefits but also influences like engine pumping on emissions and CO₂. Different to past publications, this paper focuses on testing a production feasible variable valve train technology on a fully instrumented modern Common Rail diesel engine.

Today, light connecting rods are vital to satisfying the demands of modern internal combustion engines. HYUNDAI Motor Company (HMC) has applied powder metal forged connecting rods instead of conventional hot forged connecting rods to obtain low product costs and to improve NVH characteristics and bearing reliability. Light connecting rods were developed through optimized design with high quality and low cost. Notably, the mass of a powder metal forged connecting rod is 17.7% lighter than that of a conventional hot forged type connecting rod, and its crank end is 22.5 % lighter than that of a conventional type connecting rod. Light connecting rods result in reduced crankshaft mass, so the mass of the main moving parts can be reduced. With this mass reduction, bearing reliability and NVH characteristics can be enhanced.

Due to aging of a battery over lifetime, the rated power and nominal energy capacity will be reduced compared with the initial rated power and capacity. These result in influences on the vehicle driving performance and fuel economy. To monitor and diagnose the aging of the battery, in this paper, the method of predicting the available rated power and energy capacity of Li-ion battery under in-vehicle condition is proposed. Under constant power test, available power is calculated from the estimated parameters using recursive least square method. Further, available energy capacity is evaluated through SOH(cn) defined by the ratio of initial state-of-charge (SOC) variation to present SOC (\GdSOC ⁿ /ΔSOC ⁿ ) variation under arbitrary in-vehicle driving cycles. To verify the proposed method, experiments for aging Li-ion battery are performed in hybrid electric vehicle.

Al matrix composites containing alumina (Al2O3) fibers are fabricated by the low pressure (25MPa) squeeze infiltration process which is suitable for the low cost mass production. Mechanical properties at room temperature as well as elevated temperatures (250°C, 350°C) are improved due to the presence of reinforcements. Upto 350°C, composites maintain a reasonable strength, which is much better than strength of the conventional Al alloy. Composites have equivalent wear rates to those of Ni - resist cast iron. Wear behavior is changed with the sliding speed. At low sliding speed, wear proceeds by the excessive failure of matrix and fiber, whilst, at higher sliding speed, matrix fracture near fiber plays a major role in wear. Wear resistance of 125°C is inferior to that of room temperature due to the reduction of mechanical properties followed by matrix softening and poor bonding.

The introduction of inexpensive cylinder pressure sensors provides new opportunities for precise engine control. This paper presents a control strategy of spark advance and air-fuel ratio based upon cylinder pressure for spark ignition engines. In order to extend the cylinder pressure based engine control to a wide range of engine speeds, the appropriate choice of control parameters is important as well as essential. For this control scheme, peak pressure and its location for each cylinder during every engine cycle are the major parameters for controlling the air-fuel ratio and spark timing. However, the conventional method requires the measurement of cylinder pressure at every crank angle degree to determine the peak pressure and its location. In this study, the peak pressure and its location were estimated, using a multi-layer feedforward neural network, which needs only five cylinder pressure samples at -40°, -20°, 0°, 20°, and 40° after TDC.

In order to improve the fuel consumption ratio of the vehicle, a great deal of research is being carried out to improve air-conditioning efficiency. Increasing the efficiency of the condenser is directly connected to the power consumption of the compressor. This paper describes an experimental method of using an additional water-cooled condenser to reduce power consumption and decrease discharge pressure of the air-conditioning system. First, the principle of a combined cooling (water + air) method was evaluated theoretically. Next, experimental proof was conducted with the additional water-cooled condenser. The shape and structure is similar to the plate type of the transmission oil cooler used in a radiator. Through a number of tests, it was found that it is possible is to reduce power consumption of compressor by decreasing discharge pressure.

Cooled LPL EGR is a proven means of improving the efficiency of a Gasoline Turbocharged Direct-Injection engine. One of the most significant hurdles to overcome in implementing a LPL EGR system is dealing with condensation of water near the entrance of the turbocharger's compressor wheel. A gasoline engine, and to a greater extent a spark ignition engine running on Natural Gas, will encounter enough water condensation at some steady-state conditions to damage the compressor wheel due to the high-speed collision between the compressor blades and the water droplets. As an alternative to not utilizing beneficial EGR at the condensing conditions, the team at BorgWarner have developed a LPL EGR mixer that is effective at condensing and collecting the water droplets and routing the water around the compressor wheel. The new Condensing EGR mixer was developed from the known concept of utilizing a mild venturi section to enhance EGR delivery and mixing.

Light weighting is a critical objective in the automotive industry to improve fuel efficiency. But when redesigning parts for light weight, by changing from metal to plastic, the resulting design gives NVH issues due to differences in part mass and material stiffness. Many parts were not converted from metal to plastic because of NVH issues that could not be solved. Many engine parts such as cylinder head cover, air intake manifold, oil pan and etc. previously made of metal have since long been replaced with plastic. But timing chain cover has not been replaced because of the aforementioned issue. Sealing performance due to the dynamic characteristics of the application is another challenging factor. In this paper, the key aspects of the plastic timing chain cover as well as its advantage are presented.