M.Sc. Cooper Welch


work +49 6151 16-28907

Work L6|01 123
Otto-Berndt-Str. 3
64287 Darmstadt

Internal combustion engines (ICEs) in automotive applications play a critical role in modern society. As the world continues to develop, the number of ICEs in use will continue to grow. Increasing concerns over the sustainability of such a mode of transportation on areas such as fossil fuel consumption and harmful emissions have necessitated the need for new technologies and fundamental research in internal combustion engines.

Therefore, the Institute for Reactive Flows and Diagnostics (Reaktive Strömungen und Messtechnik) aims to better understand the complex physical and chemical processes associated with internal combustion engines.

Figure 1: Single-Cylinder Optical Research Engine at TU Darmstadt

The optical engine test rig at TU Darmstadt (Fig. 1) employs an automotive engine with a quartz glass cylinder-liner and piston for optical access. The optical engine operates under motored or fired and port-fuel injection or direct injection conditions, and allows a number of simultaneous diagnostics to be performed. Along with the acquisition of the temperature and pressure, advanced optical diagnostic techniques including particle image velocimetry (PIV), laser-induced fluorescence (LIF), thermographic phosphor thermometry (TPT), Mie scattering imaging, diffuse backlight illumination (DBI), and tunable diode laser absorption spectroscopy (TDLAS) are used to gain insight into the fundamental characteristics of engine operation.

Figure 2: Engine Ignition after Direct Injection by the Spray G Injector

The interaction between the operating conditions of the engine, engine geometry configuration, engine performance, and engine emissions is studied through analyses of the flow field, direct injection spray morphology, and the instantaneous surface temperatures of engine components.

The flow fields of the engine in the vertical symmetry-plane, valve-plane, horizontal-plane, and the near-wall piston flow field yield valuable information about the cyclical engine operation. However, a continuous flow bench experiment with an outflow duct will allow a deeper analysis of the turbulent intake jet of the engine cylinder through the systematic control of variables in a simplified, yet robust experimental simulated engine operation.

Additionally, the interaction between the engine flows and the direct injection spray using an ECN standard Spray G injector (Fig. 2) is closely studied and compared with constant volume chamber (CVC) and numerical simulation data.