Optimal Speed on Small Gradients - Consequences of a Non-Linear Fuel Map

نویسندگان

  • Maria Ivarsson
  • Jan Åslund
  • Lars Nielsen
چکیده

Consequences of non-linearities in sfc, i.e. specific fuel consumption, of a heavy truck combustion engine are studied. A quasi-static analysis gives valuable insights into the intrinsic properties of the studied problem, i.e. minimization of fuel consumption on small gradients. Two objective functions are shown to give different optimal velocity trajectories on a constant gradient due to non-linearities in sfc. When a constraint is set to keep to a final time, switching between two speeds is optimal. Instead, if consumed time is part of the objective function, in addition to fuel consumption, keeping to one constant speed is optimal. However, the different optimal solutions still show similarities. For a certain significant non-linearity a specific speed range is shown to be unreachable, independent of objective function. Also under more realistic conditions, a dynamic analysis, implemented by a numerical optimizer, confirms that an alternating speed profile is optimal for the case of fixed final time.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Fuel Optimal Powertrain Control for Heavy Trucks Utilizing Look Ahead

The road topography in highways affects the powertrain control of a heavy truck substantially since the engine power is low in relation to the vehicle weight. In large road gradients constant speed is not possible to keep, which would have been beneficial otherwise, and in some uphills shifting gears becomes inevitable. If information about the road ahead, i.e. look ahead information, is availa...

متن کامل

Design, Development and Test of a Practical Train Energy Optimization using GA-PSO Algorithm

One of the strategies for reduction of energy consumption in railway systems is to execute efficient driving by presenting optimized speed profile considering running time, energy consumption and practical constraints. In this paper, by using real route data, an approach based on combination of Genetic and Particle swarm (GA-PSO) algorithms in order to optimize the fuel consumption is provided....

متن کامل

Efficient Simulation and Optimal Control for Vehicle Propulsion

Efficient drive cycle simulation of longitudinal vehicle propulsion models is an important aid for design and analysis of power trains. Tools on the market today mainly use two different methods for such simulations, forward dynamic or quasi-static inverse simulation. Here known theory for stable inversion of non linear systems is used in order to combine the fast simulation times of the quasi-...

متن کامل

Optimal Control Utilizing Analytical Solutions for Heavy Truck Cruise Control LiTH-ISY-R-2842

The problem addressed is how to control vehicle speed over a given distance on a given time such that fuel consumption is minimized. Analytical expressions for the necessary optimality conditions are derived. These expressions are essential for the understanding of the decisive parameters affecting fuel optimal driving and the analytical optimality conditions make it possible to see how each pa...

متن کامل

Experimental study of the diesel injector nozzle sediment effect on fuel spray behavior

High pressure amount of fuel in new generation diesel engines’ injector equipped with multiple and small nozzle holes has created significant improvement in the outgoing spray behavior and engine performance. On the other hand, poor fuel quality and injector nozzle embedded in high temperature combustion chamber form fundamental deposits on the nozzle leading to fuel spray inappropriate behavio...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2008