Up to now, the calibration of flow meters has been conducted at constant flow rates. However, the operational context of flow meters is characterised by the fact that they are exposed to variable, often rapidly changing flow rates. It is thus conceivable that future regulations may be introduced with a view to ensuring the performance of dynamic calibrations or the evaluation of flow meters with dynamic flow profiles. In order to facilitate such measurements, it is necessary to develop test benches that are capable of generating dynamic flow profiles of the requisite quality. Consequently, as part of the EMPIR project 'Safest' (20IND13), test benches capable of generating predefined flow profiles were developed at various research institutes. In order to achieve this, a number of different techniques were employed, including cavitation nozzles, valves, a piston system and injectors.

A transfer setup based on a Coriolis flowmeter was developed to facilitate comparative analysis of the different realisation techniques. The transfer set was subjected to comprehensive characterisation in the PTB pilot laboratory and subsequently transferred to the project partners. The partners conducted both static measurements and dynamic measurements with the defined profiles. Given the project's focus on the automotive sector, a variety of vehicle profiles based on the Worldwide harmonized Light Duty Test Cycle (WLTC) and the World Harmonized Transient Cycle (WHTC) were employed, with tests conducted using both calibration oil according to ISO 4113 and water.

In the dynamic measurements, the mass-dependent pulses of the flow meter were recorded in order to determine the flow rate over time. Subsequently, the data was analysed at PTB, where three parameters were defined for comparing the test benches: the standard deviation, the mean of the residuals and the deviation of the mass. The results for these parameters show that injectors are very suitable for achieving the vehicle profiles. The use of a piston system gave acceptable results. The valve implementation cannot be fully assessed due to lack of data. However, based on the current database, the technology appears to be of limited suitability. Conversely, the desired profiles could not be achieved with cavitation nozzles.