Automotive Powertrain Laboratory

The Automotive Powertrain Laboratory spans a broad spectrum of powertrain technologies which includes combustion engines, electric and hybrid drives with all their subfields.

Its current and future research fields are presented below:

Thermodynamic and optical combustion analysis
The Lab Automotive Powertrain is equipped with modern pressure monitoring systems and precise fuel consumption and emission measurement technology, enabling it to perform detailed thermodynamic analyses. One important tool here is “Miraculix”, a pressure curve analysis tool which has been developed in-house to compile energy loss distributions. The lab also conducts optical investigations into mixture formation and combustion with the aid of high-speed endoscopy.
The optical and electric measurement of sprays in a pressure chamber (up to 50 bar) supplements the research carried out on the engine test stands. Just as valuable is the possibility to perform optical analysis of ignition sparks in a heated flow chamber.

Simulation 1D, 3D
The Automotive Powertrain Laboratory not only undertakes experimental analyses but also simulates charge cycle, charge motion and combustion with the aid of the well-known programs GT-Power and STAR CCM+.  

Cooling circuit
This test stand is used to analyse and develop thermal management systems for electrical and electrified drives.
The tasks here are to:

• Construct radiators, hoses and pipes, actuators and sensor systems, too, as they are found in a vehicle.
• Replace drive components with heating elements to avoid high costs.
• Simulate the component temperatures and calculate the heat fluxes in parallel with the physical experiment.
• Impose the calculated heat fluxes by means of heating elements.
• Use micro-controllers for control.
• Compile real-time operating strategies through the interaction of measuring technology and simulation.

Mechanical engineering workshop
The laboratory has its own mechanical engineering workshop to support the projects carried out there.

Looking to the future:

• E-drivetrain test stand

The test stand is a compact all-round package which can be used to further develop hybrid and electric powertrains and the associated auxiliary aggregates such as power electronics and cooling circuits. This test stand complements the existing combustion engine test stands and can also handle a very wide range of tasks.
It will also facilitate the simulation of hybrid engine emissions by digitally coupling the drive unit (Dyno 1) to one of the existing combustion engine test stands and tracking a driving cycle driven by the e-drivetrain test stand with the combustion engine.

• Hydrogen test stand

The goal is to create a hydrogen test stand in the Automotive Powertrain Laboratory. The concept phase will be undertaken by students, and they will also bring the project to fruition.

Laboratory work in the Bachelor degree programmes:

• Emissions of a spark ignition engine: Cold start and lambda variation – raw emissions and exhaust gas post-treatment
• Efficiency/losses: speed, load and ignition point variation
• Charge cycle in the spark ignition engine: scavenging and internal residual gas variation
• Emissions and noise of a diesel engine: variation of fuel injection timing, exhaust gas recirculation rate and pilot injection

Laboratory work in the Automotive Engineering Master programme:

• Thermodynamic analysis on the whole engine
• Optical investigations on a single cylinder engine

Student projects and final theses:

Project work is undertaken in the 4th and 6th semesters. The Lab Automotive Powertrain regularly advertises projects which it supervises itself.

• H2 projects
• Cooling circuit in the loop
• Motor simulation: 3D CFD of charge cycle and injection processes
• Projects in collaboration with the Rennstall Esslingen racing car project
• Develop a concept for a hydrogen infrastructure on the test stand
• Develop concept strategies for hydrogen internal combustion engines and fuel cells

The Lab Automotive Powertrain also supervises projects and final theses which form part of the Master programme:

• Combustion analysis on the thermodynamic single cylinder research engine
•  Research and development relating to the combustion process in the spark-ignition engine for hybrid car applications

•  Gas discharge anemometry: development of a method to measure the internal cylinder flow

• 3 engine test stands with asynchronous machines

Power classes
- 350 kW/800 Nm
- 220 kW/525 Nm
- 150 kW/340 Nm

• Exhaust measurement

• 2 HORIBA Mexa 7170DEGR for exhaust emission components CO, CO2, NO, NO2, N2O, Total HC, CH4 and O2 as well as EGR rate

• Videoscopy

- Photron SA-X2 high-speed camera

- Storz endoscopes

• Optical injection chamber for pressures up to 50 bar
• Fuel consumption measurement

- AVL FuelExact

- AVL 733

• Particle measurement

- AVL Smoke Meter 415S

- MS4 Pegasor Particle Sensor

- AVL Opacimeter 439

• In-cylinder pressure measurement

- 2 FEV FEVIS (16 channels)

- 1 FEV CAS (8 channels)

- Sensor system Kistler/AVL

• Blow by measurement

- AVL 442

• Conditioning equipment

- Intake air, charge air, cooling water and engine oil

• Pressure and temperature flow channel

- Ignition test stand

• Wind tunnel to measure ignition sparks under flow conditions and also up to 40 bar and 180°C
• Investigation of a measuring principle using spark deflection under flow conditions
• Data acquisition system for the development and calibration of drive systems, engines and components

- AVL XION (8 channels)

• Cooling circuit test stand

A complete list with all research work, research contributions and publications since 2008 is available on the German website.