Metrological Laboratory
The MTL consists of practical exercises that are held at different institutes. All information regarding the MTL can be found on the L2P.
Important: To participate in the laboratory tutorial, you need to register at the MTL learning room (WZL). With the help of the time table and the group calendar, you can register yourself in the Campus Office for the respective laboratory tutorial group.
Experiment 5.1: Noise Measurement
Pressure changes in the air in specific frequency and amplitude regions are perceived by the human ear as sound. In acoustics, one can distinguish between pure tone, complex tone and noise, the latter being the one emitted by machines. The intensity of a noise is measured by the sound pressure level (SPL) and with the use of a Fast Fourier Transform (FFT-Analysis) it is possible to evaluate the frequency contents of the emitted noise. The A-weighted SPL is used as a standard evaluation of the relative loudness of a noise perceived by the human ear, independent of any subjective perceptions.
Experiment 5.2: Flow Rate Measurement
Since the flow is the product of the flow velocity and the flow, a number of various measurement methods were developed to determine the flow velocity.
The most widely spread determination of the rate of flow is the energetic relation of a stream with the special use of the wind pressure method. Flow meters that work with this procedure are deployable with great accuracy even at high temperatures and pressures which is why they are used to gage and calibrate almost every other flow meter.
Experiment 5.3: Concentration Measurement
The goal of the experiment is the measurement of pollutant concentration which especially occurs in the combustion process. As part of the experiment, the fundamentals of the exhaust gas measurement and the structure of the measurement chain are explained by using the utilized hardware. The measured pollutant concentrations are then used to determine the present air-fuel ratio.