Effect of the introduction of battery electric vehicles on ground-level O3 and PM2.5
-Mitigation of heat island effect and health impact-

Hiroo Hata･Norifumi Mizushima (AIST)･Tomohiko Ihara (The University of Tokyo Graduate School)

In this presentation, we will show the results of the estimation of the changes in temperature due to the mitigation of UHI effect, and the changes in ground-level O3 and PM2.5 concentration after introducing BEVs to the Greater Tokyo Area (GTA) of Japan using numerical weather prediction and regional chemical transport model. The changes in premature mortality due to the changes in O3 and PM2.5 were estimated.

Effect of Fuel Tank Pressure on Air Entrainment Phenomenon During Automobile Refueling and Its Calculation Model

Shota Yokoyama･Toshiki Iwakawa･Keiki Yamaguchi･Juan C. Gonzalez Palencia･Mikiya Araki (Gunma University Graduate School of Science and Technology)

During refueling of an automobile, air is entrained by fuel flow at the inlet of the filler pipe. In this study, a refueling experiment using water was conducted and multiphase flow inside the filler pipe was visualized using LIF. Two flow patterns were observed: spray flow and liquid film flow. A model was developed to describe the relationship between entrained air flow rate and tank pressure. The model estimates the entrained air flow rate considering the contributions of droplet pressure drag and liquid film frictional resistance.

PN Emission from Heavy Duty Vehicles Complying with Cold Start Emissions Regulation

Kazu Oshima･Hiroyuki Yamada (Tokyo Denki University)･Hidenori Konno (Toke Engineering)･Atsushi Sato･Jun Okabe･Haruya Jyo (Environment & Information)

SPN23, SPN10 and regulated gas emissions have been evaluated from Heavy Duty vehicles complying with the Japanese regulation in 2016 that include emission measurement with cold start mode. Several vehicles were tested on the Chassis Dynamometer. with World Harmonized Vehicle Cycle so called “WHVC” mode. Observed common properties were increased emissions of NOx during warming up process, and increased SPN10 emissions in high load conditions.

Brake Emission Reduction Approaches under the impact of EU7

Christof Danner (AVL List GmbH Graz)･Kinzo Takahashi･Toru Nishizawa (AVL Japan K.K.)

The Euro 7 regulations emphasize non-exhaust emissions, particularly brake emissions, under the Global Technical Regulation (GTR) 24 framework. With a stringent limit of 7 mg/km/vehicle for passenger cars and light commercial vehicles, current systems often fail to comply without regenerative braking. Challenges include measurement inaccuracies, evolving standards, and integrating reduction factors for electrification. Early solutions like brake disc coating and brake dust filters are in development, alongside plans for In-Service Conformity (ISC) and Real-Driving Emissions (RDE) testing. Manufacturers face pressure to innovate brake systems, balancing performance, comfort and emissions reduction through new materials, technologies, and testing methods.

Development of Non-Exhaust Brake Wear Emissions Measurement System for New European Regulations

Kenji Kondo (HORIBA Europe GmbH)

While the exhaust gas emissions have been reduced significantly from vehicles by the tighter regulations, the emitted proportion of non-exhaust brake wear particle emissions have been focused recently. Therefore, emissions regulation on brake wear particle emissions will be introduced in Euro 7. In this paper, the measurement technology of a brake wear particle measurement system will be reported.