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For reduction of fuel consumption, a new device “Water Jacket Spacer” which improves temperature distribution of a cylinder block bore wall was developed. In the case of a conventional cylinder block, coolant flow concentrates at the bottom and middle region of the water jacket. While temperature of the upper bore wall is high (due to high-temperature combustion gas) the temperature of the lower bore wall is low, since its only function is to support the piston. When the developed spacer is inserted into a water jacket, the coolant flow concentrates at the upper part of the jacket. As a result, cooling ability to the upper bore wall was improved and temperature of lower bore wall was increased, thereby reducing fuel consumption.

Phosphor thermometry was used during fuel injection in an optical engine with the glass piston of reentrant type. SiO2 coated phosphor particle was used for the gas-phase temperature measurements, which gave much less background signal. The measurements were performed in motored mode, in combustion mode with injection of n-heptane and in non-combustion mode with injection of iso-octane. In the beginning of injection period, the mean temperature of each injection cases was lower than that of the motored case, and temperature of iso-octane injection cases was even lower than that of n-heptane injection cases. This indicates, even if vaporization effect seemed to be the same at both injection cases, the effect of temperature decrease changed due to the chemical reaction effect for the n-heptane cases. Chemical reaction seems to be initiated outside of the fuel liquid spray and the position was moving towards the fuel rich area as the time proceeds.

In today's motorized society, various automotive technologies continue to evolve every day. Amid this trend, a new concept with respect to automatic transaxle gear-shifting has been developed. In order to materialize a new concept for shifting operation with a universal design in mind, a system has been developed: a shift-by-wire system developed specifically for hybrid vehicles. The greatest advantage of this new system is the lack of constraints associated with the conventional mechanical linkage to the transaxle. This allows freedom of design for the gear selection module. A revolutionary improvement in the ease of shifting has been realized by taking full advantage of this design freedom. In addition, this system contributes to an innovative design. For improved ease of operation, the operation force of the shift lever of this system has been dramatically reduced. For parking, the driver can engage the parking mechanism of the transaxle at the touch of a switch.

This paper presents the thermal management of a hybrid vehicle (HV) using a heat pump system in cold weather. One advantage of an HV is the high efficiency of the vehicle system provided by the coupling and optimal control of an electric motor and an engine. However, in a conventional HV, fuel economy degradation is observed in cold weather because delivering heat to the passenger cabin using the engine results in a reduced efficiency of the vehicle system. In this study, a heat pump, combined with an engine, was used for thermal management to decrease fuel economy degradation. The heat pump is equipped with an electrically driven compressor that pumps ambient heat into a water-cooled condenser. The heat generated by the engine and the heat pump is delivered to the engine and the passenger cabin because the engine needs to warm up quickly to reduce emissions and the cabin needs heat to provide thermal comfort.

The purpose of this paper is to construct the thermal analysis model by measuring and estimating the temperature at the traction contact area. For measurement of temperature, we have used a thin-film temperature sensor. For estimation of temperature, we have composed the thermal analysis model. The thin-film temperature sensor was formed on the contact surface using a spattering device. The sensor is constituted of three layers (sensor layer, insulation layer and intermediate layer). Dimensions of the sensor were sufficiently smaller than the traction contact area. The sensor featured high specific pressure capacity and high speed responsiveness. The thermal analysis model was mainly composed of three equations: Carslaw & Jaeger equation, Rashid & Seireg equation and heat transfer equation of shear heating in oil film. The heat transfer equation involved two models (local shear heating model at middle plane, homogeneous shear heating model).

1 Recently, demand for small-bore compact vehicle engines has been increasing from the standpoint of further reducing CO2 emissions. The generalization and formulation of combustion processes, including those related to emissions formation, based on a certain similarity of physical phenomena regardless of engine size, would be extremely beneficial for the unification of development processes for various sizes of engines. The objective of this study is to clarify what constraints are necessary for engine/nozzle specifications and injection conditions to achieve the same combustion characteristics (such as heat release rate and emissions) in diesel engines with different bore sizes.

Small bore diesel engines often adopt a two-valve cylinder head and a non-central injector layout to expand the port flow passage area. This non-central injector layout causes asymmetrical gas flow and fuel distribution, resulting in worse heat losses and a less homogenous fuel-air mixture than an equivalent four-valve cylinder head layout with a central injector. This paper describes the improvement of piston bowl geometry to achieve a more homogeneous gas flow and fuel-air mixture. This concept reduced fuel consumption by 2.5% compared to the original piston bowl geometry, while also reducing NOx emissions by 10%.

This paper describes impact kinematics and injury values of Hybrid III AM50, THOR AM50 and THUMS AM50 in simulated oblique frontal impact conditions. A comparison was made among them in driver and passenger seat positions of a midsize sedan car finite element (FE) model. The simulation results indicated that the impact kinematics of THOR was close to that of THUMS compared to that of the Hybrid III. Both THOR and THUMS showed z-axis rotation of the rib cage, while Hybrid III did not. It was considered that the rib cage rotation was due primarily to the oblique impact but was allowed by flexibility of the lumbar spine in THOR and THUMS. Lateral head displacement observed in both THOR and THUMS was mostly induced by that rotation in both driver seat and passenger seat positions. The BrIC, thorax and abdominal injury values were close to each other between THOR and THUMS, while HIC15 and Acetabulum force values were different.

The quantity of heavy components in fuel is increasing as automotive fuels diversify, and engine oil formulations are becoming more complex. These trends result in the formation of larger amounts of carbon deposits as reaction byproducts during combustion, potentially worsening the susceptibility of the engine to knock [1]. The research described in this paper aimed to identify the mechanism that causes knocking to deteriorate due to carbon deposits in low to medium engine load ranges, which are mainly used when the vehicle drives off and accelerates. With this objective, the cylinder temperature and pressure with and without deposits were measured, and it was found that knocking deteriorates in a certain range of ignition timing.

Sled tests focused on pelvis behavior and submarining can be found in the literature. However, they were performed either with rigid seats or with commercial seats. The objective of this study was to get reference tests to assess the submarining ability of dummies in more realistic conditions than on rigid seat, but still in a repeatable and reproducible setup. For this purpose, a semi-rigid seat was developed, which mimics the behavior of real seats, although it is made of rigid plates and springs that are easy to reproduce and simulate with an FE model. In total, eight PMHS sled tests were performed on this semi-rigid seat to get data in two different configurations: first in a front seat configuration that was designed to prevent submarining, then in a rear seat configuration with adjusted spring stiffness to generate submarining. All subjects sustained extensive rib fractures from the shoulder belt loading.

The reduction of the heat loss from the in-cylinder gas to the combustion chamber wall is one of the key technologies for improving the thermal efficiency of internal combustion engines. This paper describes an experimental verification of the “temperature swing” insulation concept, whereby the surface temperature of the combustion chamber wall follows that of the transient gas. First, we focus on the development of “temperature swing” insulation materials and structures with the thermo-physical properties of low thermal conductivity and low volumetric heat capacity. Heat flux measurements for the developed insulation coating show that a new insulation material formed from silica-reinforced porous anodized aluminum (SiRPA) offers both heat-rejecting properties and reliability in an internal combustion engine. Furthermore, a laser-induced phosphorescence technique was used to verify the temporal changes in the surface temperature of the developed insulation coating.

Recently, engines achieving high power levels are becoming increasingly common. The trend is toward increasing the inflow of lubricating oil into the crankcase through several factors (for example, increasing the flow rate of the cooling oil jets in order to reduce the thermal load of the pistons). In addition, the mechanical losses induced by the motion of the crankshaft and connecting rods through the additional oil are intensified due to the higher engine speeds at maximum power. In this article, we confirmed a method of separating the pumping loss and the agitation loss by measuring the pressure in the crankcase and an empirical formula was found for predicting pumping loss from displacement and ventilating area. We also investigated the effect of reducing the lubrication oil flow rate, as well as other factors affecting the oil flow, on the mechanical loss at high engine speeds.

The experiment-based droplet impinging breakup model was applied to a fan shaped spray and the impinging behavior was analyzed quantitatively. Evaluation of the quantitative results with validation tests verified the following. The model enables prediction of fan shaped spray thickness after impingement caused by the breakup of fuel droplets, which could not be represented with the Wall-Jet model, widely used at present. Fuel film movement on a wall is negligible when the injection pressure of the fan shaped spray is high and the spray travelling length is not too short. The proposed heat transfer coefficient between fuel film and the wall is too small to represent the vaporizing rate of the fuel film.

Through a polymer design and precise morphology control, The Super Olefin Polymer, TSOP-1 and TSOP-5 were developed for the material consolidation of interior and exterior parts, respectively. Due to a good balance of TSOP performance, several conventional materials were consolidated into one material for each application. Accordingly, considerable amounts of weight reduction and cost savings have been obtained. In addition to the excellent recyclability of TSOP, the coated bumpers collected from the market were re-utilized through paint decomposition technology. The first dashboard construction, molded partially with foam-padded skin, was also realized. The current amount of TSOP used in a vehicle is about 30% of the total amount of plastic materials. Through the usage of TSOP, 70% of the material consolidation has been achieved.

Small bore diesel engines often adopt a two-valve cylinder head and a non-central injector layout to expand the port flow passage area. This non-central injector layout causes asymmetrical gas flow and fuel distribution, resulting in worse heat losseses and a less homogenous fuel-air mixture than an equivalent four-valve cylinder head layout with a central injector. To improve these problems Toyota applied a new concept which was characterized by tapered shape design on the upper portion of the piston and low compression ratio to achieve more homogeneous gas flow and fuel-air mixture. This paper describes the impact of new combustion concept and the mechanism of the improvement by 3D-CFD analysis and optical measurement.

To meet the market requirement for headlamps having lower power consumption, high photometric performance and long life whilst providing new styling opportunities, it has been anticipated that LED light sources would provide the necessary technological basis. Against this backdrop, Koito has succeeded in developing the necessary headlamp technologies and commercializing the world's first headlamp utilizing white LED's. The key point is that the various challenges associated with the development of an LED headlamp such as the commercial application of a synthesized light distribution, control of the light axis structure for the multi-lamp system, development of adequate thermal management for the cooling of the LED's and the achievement of volume production of the lamps have been successfully overcome.

Abnormal combustion referred to as Low Speed Pre-Ignition (LSPI) may restrict low speed torque improvements in turbocharged Direct Injection (DI) - Spark Ignition (SI) Engines. Recent investigations have reported that the auto-ignition of an engine oil droplet from the piston crevice in the combustion chamber may cause unexpected and random LSPI. This study shows that engine oil formulations have significant effects on LSPI. We found that the spontaneous ignition temperature of engine oil, as determined using High-Pressure Differential Scanning Calorimetry (HP-DSC) correlates with LSPI frequency in a prototype turbocharged DI-SI engine. Based on these findings, we believe that the oxidation reaction of the oil is very important factor to the LSPI. Our test data, using a prototype engine, shows both preventative and contributory effects of base oil and metal-based engine oil additives.

To evaluate the influence of FAME, which has poor oxidation stability, on engine oil performance, an engine test was conducted under large volumes of fuel dilution by post-injection. The test showed that detergent consumption and polymerization of FAME were accelerated in engine oil, causing a severe deterioration in piston cleanliness and sludge protection performance of engine oil.

When the air conditioning (A/C) is turned on, the intake air to the HVAC is cooled at the evaporator. This is not only used for cooling the air temperature but also to dehumidify. Therefore, for a typical automatic climate control system, A/C will automatically operate even in winter (cold ambient temperature conditions) in order to prevent the windows from fogging despite its effect on fuel economy. In some applications, a humidity sensor is installed on top of the windshield and when the probability of fogging is low the A/C operation is disabled automatically to prevent unnecessary compressor operation which can increase fuel consumption. However, humidity sensor is not widely adopted as it requires some space to be installed and the cost is relatively expensive compared with other HVAC equipped sensors. In this study, a system was invented that disables the compressor operation when the fogging probability is low without using the conventional humidity sensor.

As a result of recent improvements in engine efficiency, vehicle heating performance has decreased and the demand for auxiliary heat sources is increasing. To help meet this need, we have developed an auxiliary heat system known as the “Hot Gas Heater”. The Hot Gas Heater uses components common to the vehicle air-conditioning system that are not used during winter. However, there are some concerns with this system. In this paper we describe our solutions to these problems. We reduced gas flow noise through multi-stage pressure reduction, and prevented fogging by adding “water retention memory” and “evaporator outlet air temperature control” functions to the system. As a further benefit, we developed a New Accumulator Cycle that moves the cooling cycle accumulator tank to the high-pressure side.