New primary standard for dynamic pressures

Project news

Dynamic pressure measurement is a key requirement for process control in many demanding applications, such as automotive, marine and turbine engines, manufacturing processes, and ammunition and explosion safety. Current practice of calibrating pressure sensors only under static conditions limits the achievable measurement accuracy. VTT MIKES has developed a new primary standard for dynamic pressures up to 6000 bar. The high-level expertise of our researchers and engineers and more than a decade of experience in developing dynamic pressure solution was a key to winning the public bidding process to build and deliver the standard to the National Metrology Institute of Poland.

The new measurement standard is based on the drop weight method, in which a weight is dropped onto a piston that seals a measurement chamber filled with liquid, causing a pressure pulse of millisecond duration inside the chamber. Knowing the mass of the drop weight and the area of the piston, pressure can be calculated based on interferometric measurement of the acceleration of the weight during impact.

While similar devices have been constructed previously, the new device is a significant improvement in many aspects. For example, the unique design of applying air bearings for guiding the drop weight results in a vertical well controlled impact, which effectively reduces unwanted tilt and vibrations that would otherwise deteriorate the measured acceleration signal. As a results of these improvements, the new primary dynamic pressure standard will enable SI traceable calibrations of dynamic pressure sensors up to 6000 bar with the state-of-the-art accuracy of less than 2 %. Moreover, the development of the device took less than a year, an asset in itself.

The new primary standard was delivered in December 2023 to the to the National Metrology Institute of Poland, the Central Office of Measures (GUM), new laboratory located in Kielce. The standard provides GUM with unique calibration capabilities and thus opens up new business opportunities, not only in ammunition and explosion safety, but more widely where accurate dynamic pressure measurement is a key requirement.

Dynamic measurements are one of the focus areas of VTT MIKES, so we will continue to develop more accurate dynamic pressure measurement methods. The lessons learned in the process of developing the primary standard will be of great importance in this development work as well as in future projects on dynamic pressure. Consequently, VTT MIKES offering in dynamic pressure calibrator technology covers a wider pressure range than ever before.

For our customers, we offer:

  • an easy-to-use pressure calibrator for day-to-day use in industry
  • a primary standard for National Metrology Institutes (NMI) and high-end calibration laboratories where the best achievable accuracy is required
  • reliable and SI-traceable calibration services for dynamic pressures up to 1000 bar.

You can find more information in the brochure: State-of-the-art dynamic pressure calibration solutions. Customers are welcome to utilize our facilities or just send their transducers to be measured by our experts.

Read also the blog Dynamic or reliable measurement? in our previous newsletter.

Richard Högström
Richard Högström
Research Team Leader