Reducing the Fuel Consumption of Urban Scooter Fleet via Integrating Traffic Simulation in Vehicle Design

Abstract

Vehicular tailpipe emissions are among the biggest impact to urban air quality and also the largest threats to the residence's physical health One mean of reducing these hazardous emissions is by reducing the fuel consumption of on-road vehicles The amount of fuels used in urban vehicle fleets depends on a number of factors including how engines are designed how powers are transmitted to the tires and how drivers behave in city traffic Although design for optimal fuel efficiency has been a major subject in automotive research their true impacts need to be evaluated in more realistic environment with human and traffic The validity of a vehicle design require an on-road environment with drivers behaviors as those in the real-world In this research we focus on the scooter fleet that has the biggest impact to the city of Tainan and redesign their transmissions to achieve the minimal overall fuel consumption We integrated traffic simulations with mixed fleets as a way to evaluate the scooter/driver behaviors in reality and focus on the power transmissions than its generation at the engine to reflect the urban driving scenario Continuous variable transmission (CVT) commonly implemented in scooters and motorcycles have recently been applied to commercial vehicles for their ability to maintain high fuel economy compared with traditional transmissions Evaluating the performance of a CVT in the current backward simulation approach require the entire driving cycle know as an a priori In realistic a direct simulation method should be used with only the engine map and throttle control being the input and the while velocity/acceleration/driving pattern being the outcome In this work a direct CVT simulation technique is established and integrated with traffic simulation using cellular automata for real-world evaluations The result of our development is a 31-variable direct simulation CVT design tool and 14-parameters NS traffic simulation model The design for a single-lane traffic condition can be evaluate by NS model and we use the results to feedback to the CVT system then adjust the parameters to achieve the target of lower fuel consumption With series of simulating processes the urban vehicle's fuel consumption can be reduced around 12% by parameter adjusting in different traffic conditions when CVT system begin to perform its capabilities And these information also provide designers or groups another indicative tendency to reduce the fuel consumption in the vehicle design field

Date of Award	2015 Aug 10
Original language	English
Supervisor	Jahau Lewis Chen (Supervisor)