B5868 - CONTROL AND TESTING OF OFF-HIGHWAY POWERTRAINS

Learning outcomes

The course has the objective of providing a wide comprehension of modern off-highway propulsion systems, focusing on their architecture, functionality, environmental impact, control and thermal management systems, considering the current and next emission standards and homologation regulations. Students will be able to model dynamic and thermal systems, with a control-oriented approach for off-highway powertrains (Internal Combustion Engines-, Hybrids- and Hydrogen-based), high and low pressure systems, power transmissions and to design and execute the testing activities during the powertrain development and homologation phases. The course provides the competences necessary to develop control strategies based on mathematical models of the system (powertrain and / or vehicle), and oriented to the minimization of fuel consumption and pollutant emissions. Thanks to the hands-on sessions offered during the course, students will also master their ability to process experimental data and to validate in a virtual environment advanced control functions, while further developing their mindset towards problem solving, team working and effective technical reporting.

Course contents

Introduction/definitions

• Definitions: features of thermodynamic cycles, work/power calculation of thermodynamic cycle, definition of main performance and combustion indexes
• Engine layouts for off-highway vehicles
• Supercharging and Turbocharging
• Aftertreatment systems and pollutant production (in particular for Diesel engines): oxidation catalyst, selective catalytic reducers. Regulations (Stage V, Tiers 3-4)

  Engine modeling and control

• Lambda controller and DI injector modeling
• PID controller
• Air flow estimation and measurement
• Mass air flow through orifice (EGR valve, throttle valve at the exhaust), potentially reversed equation to determine the target section with a target mass flow. Calculation of critical pressure ratio
• Torque calculation and control (effects of SOI/combustion phase and lambda)

  Electrification

• Introduction to diesel engines electrification (general benefits in terms of efficiency and drivability for on-field operations)
• Electrification steps:
  • Electrification of auxiliar systems
  • Diesel-electric: engine-driven generator
  • Hybrid-electric
  • Full-electric: battery electric tractors, fuel cell electric tractors
• Definition of degree of hybridization
• Electric hybrid layouts

  Powertrain testing and calibration

• Introduction to the engine test cell (objectives and types of measurements)
• Dynamometric brakes
• Main sensors:
  • Indicating system
  • Exhaust gas temperature measurement
  • Fuel flow measurement

The course will be integrated with seminars hold by engineers from companies and a possible visit to the engine test cell of Industrial Engineering Department of UniBo.

Readings/Bibliography

• Notes taken by the students and lecture material provided by the Professor
• G. Ferrari, "Motori a Combustione Interna", Esculapio
• J.B. Heywood, "Internal Combustion Engine Fundamentals", McGraw Hill

Teaching methods

Teaching involves theoretical frontal lessons carried out with the help of multimedia systems (PowerPoint slides and digital notes). Moreover, the main screen and the audio of the lectures will be recorded too.

All the teaching material mentioned above will be available at the end of each lesson through the VirtuaLe (https://virtuale.unibo.it/) and Panopto (https://unibo.cloud.panopto.eu [https://unibo.cloud.panopto.eu%0D/] ) platforms.

Assessment methods

The exam will take place at the end of the course according to the official exam session calendar.

The final assessment consists of an oral examination.

During the examination, students are required to answer 3 questions, to assess their understanding and application of the course content.

The exam is passed is the student gets a sufficient mark for each question.

Teaching tools

PowerPoint presentations, digital notes, lectures recordings

Office hours

See the website of Alessandro Brusa