Motor test bed with high-speed camera

• Subject Area: Fluid Mechanics, Technical Thermodynamics and Thermal Energy Engineering
• Term: Funded in 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 495866642

This application essentially involves equipping an engine test bench with the necessary components and equipment for the optical analysis of processes in the internal combustion engine. The core of the test bench, which is already available to the working group, is an optical single-cylinder passenger car engine that has a quartz glass ring instead of a metallic cylinder liner. This provides good optical accessibility to the combustion chamber. In the future, optical analyses are to be carried out on this engine in the combustion chamber, which will enable a deeper understanding of the processes taking place in order to derive targeted measures that will lead to an increase in efficiency and a reduction in emissions.Additional equipment is required to carry out the intended research work in the field of optical analysis. The main equipment of the application is a high-speed camera system consisting of the UV-capable camera and a UV-capable endoscope, which also allows observation axes through the cylinder head. The intention is to visualize the combustion process and pollutant formation. For the simultaneously required thermodynamic characterization of engine operating points, an indication system is needed to record measured values with high temporal resolution, such as cylinder pressure, ignition and injection signals. For the engine operation itself, a test bench control system is required to record and process all relevant measured variables (speed, torque, temperatures, pressures, etc.) and to control the engine operation. Furthermore, a programmable engine control system is required that controls fuel injection and ignition depending on the boundary conditions and specifications at the test bench. A gas-pressurized accumulator with pressure measurement is to be used for fuel supply. The fresh air mass is to be detected by an air mass meter, and the desired ratio of air and fuel mass is to be controlled by a lambda meter.Since engines often operate in fired mode for only a very short time during optical analysis - in some cases only a few cycles - steady-state conditions are seldom encountered. In order to nevertheless achieve the best possible reproducibility, it is advisable to use a synthetic admixture for exhaust gas recirculation. This requires appropriate volume flow controllers for the individual gaseous components.On the building side, some modifications are necessary in the engine installation room. On the upper floor of the building, there is a conditioning unit for the fresh air supply and an exhaust gas extraction system. Ceiling penetrations are necessary to connect the engine to both units, as well as the connection itself. Furthermore, investigations of an engine operation with hydrogen are to be realised, which means an extension of the test stand with the necessary safety devices and connections to a hydrogen supply.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Prüfstandsystem mit Hochgeschwindigkeitskamera
• Instrumentation Group: 5430 Hochgeschwindigkeits-Kameras (ab 100 Bilder/Sek)
• Applicant Institution: Karlsruher Institut für Technologie
• Leader: Professor Dr. Thomas Koch