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The reduction of CO2 emissions is one of the most important challenges for the automotive industry to contribute to address global warming. Reducing friction of internal combustion engines (ICEs) is one effective countermeasure to realize this objective. The improvement of engine oil can contribute to reduce fuel consumption by reducing friction between engine parts. Electrification of ICE powertrains increases the overall efficiency of powertrains and reduces the average engine oil temperature during vehicle operation, due to intermittent engine operation. An effective way of reducing engine friction is to lower the viscosity of the engine oil in the low to medium temperature range. This can be accomplished while maintaining viscosity at high temperatures by reducing the base oil viscosity and increasing the viscosity modifier (VM) content to raise the viscosity index (so-called “flat viscosity” concept).

In recent years, the realization of carbon neutrality has become an activity to be tackled worldwide, and automobile manufacturers are promoting electrification of power train by HEV, PHEV, BEV and FCEV. Although interest in BEV is currently growing, vehicles equipped with internal combustion engines (ICE) including HEV and PHEV will continue to be used in areas where conversion to BEV is not easy due to lack of sufficient infrastructures. For such vehicles, low-viscosity engine oil will be one of the most important means to contribute to further reduction of CO2 emissions. Since HEV requires less work from the engine, the engine oil temperature is lower than that of conventional engine vehicles. Therefore, the reduction of viscous resistance in the mid-to-low temperature range below 80°C is expected to contribute more to fuel economy. On the other hand, the viscosity must be kept above a certain level to ensure the performance of hydraulic devices in the high oil temperature range.

Attribute to high heat transfer rate and less complexity, the Helical coil sub-cooled condenser (HCSCC) can provide the most innovative and unique application for the air conditioning system. In the case of automobiles, reduction in air-conditioning load may diminish the vehicular emission, and power consumption as the air-conditioning load is the most power-consuming components after the engine load. Moreover, to solve the problem, we focus on the helical type heat exchanger. It may play a vital role in reducing the weight and increase the performance of the small engine because of the compact structure and lighter weight. The compressor unit is the most vital component of the refrigeration cycle, but the condenser unit is also one of the most critical devices, and the author tried to reduce the power consumption by enhancing the performance of the condenser.

This paper represents the adaptation of turbo charger to single cylinder 450cc SI engine which is used for the student formula competition. The experiment and 1D engine simulation called as GT-Power were performed to confirm the effect of valve profile, compression ratio and air fuel ratio on the engine performance under the naturally aspirated condition. The maximum valve lift of the intake valves increased 27% and that of the exhaust valves increased 15% as compared with the low profile cam. The compression ratio was increased from 12.3 to 13.5 by changing the piston top land length in order to improve the thermal efficiency. It was confirmed that the torque peak was moved from 6000 rpm to 8000 rpm by changing the valve profile. Furthermore, turbo charger was adapted to the engine as changing the capacity of the turbocharger, the maximum boost pressure and the air fuel ratio.

For further development of the thermal efficiency of SI engines, the robust control of the air-fuel ratio (A/F) fluctuation is one of the most important technologies, because the A/F is maintained at the theoretical constant value, which causes the increase of the catalytic conversion efficiency and the reduction of pollutant emission. We developed the robust controller of the A/F, which is the method to change the fuel injection rate by using the feed-forward (FF) controller considering the heat transfer at the intake system. The FF controller was verified under transient driving conditions for a single cylinder, and the A/F fluctuations were reduced at approximately 84%.

The paper reviews the experimental development of fuel economy of engine powering the 2012 Formula SAE single seat race car of the University of Sophia. The balance of high power and low fuel consumption is biggest challenge of racing engine. It was found that improving the efficiency of engine by supercharging as a way to achieve that. In order to adapt the supercharger for the engine, the important design points are below: It was found that intake air blow-by gas at combustion chamber is increased in low engine speed. To improve that, the valve overlap angle was changed to adopt supercharged engine and improve effective compression ratio. Typically the racing engine demands maximum torque for performance but that does not imply that the air fuel ratio should be rich than theoretical. The point is the maximum torque of the engine is proportional to the amount of air intake. Therefore, supercharged engine is possible to increase the supercharging pressure for bigger torque.

Nowadays, cornering performance of FSAE (Formula SAE) cars are dramatically improved due to less mass, kinematic developments and tires. In such circumstance, under high speed conditions, aerodynamical devices work better. It had been decided to attach aerodynamical devices that consist of front wing, rear wing, diffuser (floor) and deflector for SR11 (Fig. 1, Table 1), a FSAE car developed by Sophia Racing (Japan). Fig. 1 SR11 Table 1Vehicle configuration of SR11 To start with developing aerodynamical devices, it had been assumed that how they work. Lap time simulation had been done with VI-car-realtime, which shows the laptime could be shorten by 2 seconds of 60 seconds for a usual FSAE endurance course with 60kgf at 60km/h downforce. Dragforce had been assumed to work well while once, it had been supposed to have a bad influence for laptime.

This research focuses on the improvement of torque at the middle engine speed of a motorcycle engine with resonance supercharging. The resonance supercharging intake system is realized with a simple modification to the intake collector geometry. A one-dimensional computational model is employed to simulate the pressure wave propagation and to optimize the configuration of it. The experiments confirmed the increase in the engine torque for the entire operation range and the maximum gain of 33% was achieved at 8500rpm. The resonance effect is further investigated through three-dimensional simulation, in which the intake airflow rate, static pressure distribution are analyzed.

In this paper we propose a new multi-functional steering wheel switch for HVAC and audio systems. This new switch has five buttons on the front side of the spoke area and one button with vibration on the backside of it. Drivers can operate either HVAC or audio functions with the front switches, and HVAC or audio mode can be alternatively selected by pressing the back switch. Since different vibration modes are assigned for the HVAC and audio mode, drivers can also easily recognize which function can be operated. By changing the assignment of the mode in this way, the switch can operate more than 10 functions with 6 buttons allocated on the spoke area. Several kinds of evaluations were performed in order to develop this multi-functional switch. At first, to optimize the positions of the buttons, the behaviors of thumbs and fingers were measured. Also the physical workload of the thumb motion and middle fingers' postures was evaluated when subjects operated the switches.

Temperature distribution as the flame propagated and contacted to the wall of the combustion chamber was measured by real-time holographic interference method, which mainly consisted of an argon-ion laser and a high-speed video camera. The experiment was done with a constant volume chamber and propane-air mixture with several kinds of equivalence ratios. From the experimental results, it can be found that the temperature distribution outside the zone from the surface of the combustion chamber to 0.1mm distance could be measured by counting the number of the interference fringes, but couldn't within this zone because of lacking in the resolution of the used optical system. The experimental results show that the temperature distribution when the heat flux on the wall increases rapidly and when the heat flux shows the maximum value are quite different by the equivalence ratio.

The electronic controlled carburetor and ignition system has been developed. In accordance with various working conditions of the engine, the system adjusted corresponding control parameters; air fuel ratio and ignition timing, therefore it could keep the engine working on the optimal conditions. Through analyzing overall performance of the engine based on the experimental data, we had concluded that the specific fuel consumption was improved about 8-10%, and the exhaust emission performance was improved correspondingly after electronic control, the improved ratio was about 10% for HC emission and 97% for CO emission.

The purpose of this study is to find the suitable working conditions of a Pressure Wave Supercharger (PWS) that is coupled to a gasoline engine experimentally. The working condition is validated by stationary measurements on an engine dynamometer. To achieve an easier system structure, it was examined to use the engine output for driving of PWS. As a result, it was confirmed that the engine coupled with PWS could be driven by making the ratio of the PWS rotor speed and the engine speed constant.

In the 17th century, Christiaan Huygens invented the first engine to save the labor, which is humanism. Nowadays, both gasoline (SI) and diesel (CI) engines hold the definite position as the prime mover of the current surface transport vehicles due to their superior power, energy density, and fuel economy. Although these engines give exceeding convenience to human life, they also have become the vanguard of environmental disruption. From this viewpoint, the author has tried to give a historical review and perspective on engine developments. Although it is said that further emission controls in CI engines are quite difficult, recent research work and prediction for both lower emissions and better fuel economy are discussed. It is concluded that CI engines will co-exist with SI engines in the future, part of which will be used in hybrid systems. Fuel cells will be widely utilized, and hydrogen internal combustion engines would be expected as well.

The relations of luminous intensity of the radicals, CH, C2, and OH radical, and the equivalence ratio, ϕ under high combustion pressure region (7.0MPa maximum) were investigated. Luminous intensity of each radical and combustion pressure were experimentally obtained using a constant volume combustion chamber. It was found that luminous intensity of each radical can be expressed as a function of ϕ and the combustion pressure. The estimation of ϕ was done within the region, 0.8<ϕ<1.2 and 2.0MPa

This book examines the development of the engine from a historical perspective. Originally published in Japanese, The Romance of Engines' English translation offers readers insight into lessons learned throughout the engine's history. This book belongs on the bookshelves of all engine designers, engine enthusiasts, and automotive historians. Topics covered include: Newcomen's Steam Engine The Watt Steam Engine Internal Combustion Engine Nicolaus August Otto and His Engine Sadi Carnot and the Adiabatic Engine Radial Engines; Piston and Cylinder Problems Engine Life Problem of Cooling Engine Compartments Knocking; Energy Conservation Bugatti; Volkswagon Rolls Royce Packard Daimler-Benz DB601 Engine and more!

A historical review of Japanese turbocharged diesel engines for heavy duty vehicles is described, and newly developed turbocharged diesel engines of HINO are introduced. The design features of these engines include new turbocharging technologies such as highly backward curved impeller for compressor blade, variable controlled inertia charging and waste gate. Laboratory and field test results demonstrated better fuel economy and improved low speed and transient torque characteristics than the predecessors. Several operational experiences, technical analysis and reliability problems are discussed.

This paper presents technical solutions and a development process to accomplish not only superior fuel economy but also excellent driveability with a turbocharged diesel engine for heavy duty trucks. For better fuel economy, one of the basic considerations is how to decrease the friction losses of the engine itself while keeping the required horsepower and torque characteristics. A high boost turbocharged small engine offers this possibility, but it has serious disadvantages such as inferior low speed torque, poorer accelerating response, insufficient engine braking performance, and finally not always so good fuel consumption in the engine operating range away from the matching point between engine and turbocharger. These are not acceptable in complicated traffic conditions like those in Japan - a mixture of mountainous and hilly roads, city road with numerous traffic signals, and freeways.

In a diesel engine, the mixing of the fuel spray and in-cylinder air controls rate of beat release during combustion, namely it will determine the thermal efficiency, maximum output and gas or noise emission, etc. Therefore, it is important to measure the droplet size and its volume density distribution in diesel fuel sprays. The optical measuring method, which includes a light scattering and holographic technique, seems the only feasible method for analysing these unsteady characteristics of fuel sprays. The light scattering technique described herein was based upon Mie scattering theory, and the droplet size and volume density distribution of fuel sprays were calculated from the combination of the light extinction and the forward-to-backscattering ratio of Mie scattering intensity. The volume density and droplet size distribution of fuel sprays were obtained from the light intensity distribution on a photograph of fuel sprays.

Described herein is the tuning of the combustion system of a direct injection type diesel engine to obtain low emission level and better fuel economy. Though the most important method of emission control for a direct injection system is considered to be timing retardation, it brings a higher level of smoke density and fuel consumption. In order to remove these faults, the authors developed a new combustion system based on a newly designed intake port which provides a favorable local mixing of fuel droplets and air in the combustion chamber for ignition by means of air turbulence. This new combustion system was analyzed with high speed photographs which were taken from the underside of the piston to enable observing the whole combustion chamber. Favorable characteristics of ignition and burning pattern of the new system were recognized by this analysis.