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Fluid flow


On the basis of the Units and Time Act, the subject area "Flow Rate" deals with the realization and dissemination of the units for the flow measurands "mass", "flow rate" and "thermal energy measurement" of liquids as well as "mass", "flow rate" and "flow velocity" of gases (low and high pressure). For this purpose, on the one hand, research and development work is carried out with the aim of adapting the range of realization and the achieved measurement uncertainty of the realization to the growing requirements of science and industry. On the other hand, comprehensive research work on energy efficiency addresses important political and economical challenges of the "energy transition". Furthermore, the Measuring and Verification Act lays down various tasks to ensure the uniformity and correctness of flow rate measurements in the field of legal metrology. In detail, the following tasks are performed:

  1. Safeguarding and development of the international top position in the realization of the units for the flow measurands of liquids and gases

  2. Creation of closed systems to ensure traceability of the gas and liquid measurements to the respective national standards of PTB

  3. Safeguarding of the uniformity and correctness of all mass, flow rate and flow velocity measurements of liquids and gases, also in the field of alternative energies (e.g. biofuels, biogases, wind energy), in particular for the interests of consumer protection, environmental protection and health protection; creation of internationally uniform provisions for conformity assessment, approval and certification as a precondition for the recognition of the corresponding results in Europe and worldwide.

  4. Development of procedures for in-situ measurements of thermal energy with smallest uncertainties in conventional power plants and in solar-thermal power plants.