Abstract
Keywords- Monofuel, CNG-Vehicle, Simulation, Real-world
Based on questions of energy saving, the problems of greenhouse gas emissions as well as air quality, the European countries aim at a stronger diversification of energy sources for traffic. Gaseous energy sources, like natural and bio gas should become an essential fundament as fuel, which offer lower CO2 and pollutant emission even because of their chemical composition, higher energy density and knocking resistance.
The research within the project CNG600 was focused on the development of a monofuel CNG standard van with an operation range of more than 600 km. The use of new simulation and experimental methods, the optimization of the manual gear shift powertrain, application of a light weight storage system and new gas valve technology lead to extremely low CO2 emission of about 120 g/km.
The gas system of the vehicle was developed for monofuel operation. The methane storage system was extended, which resulted in increased fuel mass in the vehicle. The application of low weight pressure vessels made of composite materials helped to keep the overall vehicle mass low. The gas system was equipped with a new valve technology and separated in high pressure, middle pressure and low pressure sections resulting in an overall optimized system for an automotive application.
The vehicle longitudinal performance and fuel consumption were simulated during the development process. Consequently, necessary drive train improvements were defined to ensure lower fuel consumptions in city as well as on highway driving routes. In order to support the fuel efficiency of the propulsion system by low power demand of the vehicle, driving resistance minimization measures were implemented as well. The developed concept was applied on a standard van and realized as prototype.
Finally, real world measurements conducted with the prototype vehicle on different driving routes supported the validation of the expected results. Under different driving conditions the CO2 emissions stayed on a very low level.