Engine Test Bench

The ITV test bench is equipped with oil, water, and fuel conditioning systems in order to maintain stationary boundary conditions. The air supply is ensured by an external charger unit and the desired intake air temperature is provided by a heater and charge air coolers. The engine load is represented by a DC motor (speed-controlled) equipped with a torque meter. In the intake and exhaust manifolds and runners, the gas temperatures are metered with thermocouples, and the static and instantaneous pressures are measured with piezoresistive and piezoelectric sensors, respectively. The control of the engine (i.e., intake pressure, exhaust pressure, injection timing, duration, etc.) is performed with a customized engine control unit (ECU). Average exhaust emissions, e.g., NO_x, total-HC, CO, CO₂, O₂, and soot, are measured on a partial mass flow sampled with a heated line connected to the appropriate analyzers. Additionally, ITV has the possibility to measure cycle-resolved total-HC and NO_x emissions with fast measuring devices. The engine cylinder is equipped with a piezoelectric pressure transducers in conjunction with the charge amplifiers. Hereby, reliable thermodynamic data determination is ensured. The analysis of in-cylinder parameters, e.g., pressure, indicated values, combustion and heat release analysis, are evaluated in a thermodynamic real-time analysis module over multiple consecutive cycles.