Optical Methods for Vibration Measurements in Nuclear Applications

In a recent Energiforsk report, methods for optical vibration measurement were surveyed. These methods show promising results for a denser spatial resolution offering high precision and cost effectiveness with a non-contact approach.

Vibration problems in nuclear power plants can lead to extensive loss of income due to operating at reduced power, or even to down time. Having up to date vibration monitoring systems is an important tool to discover problems early and address the root cause.

Optical vibration measurement systems are examples of such tools that has proven to be capable of measuring vibrations in a harsh industrial environment. However, suitability of these methods for a nuclear power plant environment have not been investigated until now.

In a recent Energiforsk report all commercially available optical measurement methods, relevant for the nuclear power sector, where surveyed. These methods were shown to provide multiple advantages compared to the conventional vibration measurement sensors. The methods surveyed in the report, had denser spatial resolution than conventional measurement methods can practically reach.

Technological developments within this field is moving fast and there is a positive outlook for continued trials and application within the nuclear sector, says Monika Adsten program manager for the Vibrations in nuclear applications research program.

This speedy development has led to a wide range of different methods for capturing vibration behaviour and target specific characteristics. Three methods distinguished themselves in the report. The Motion Magnification method was found suitable for preliminary troubleshooting purposes and 3D SLDV and 3D Digital Image Correlation were found to be applicable for vibration monitoring of large targets in a nuclear power plant environment.

This type of measurement method is easy to set up and get running without much preparation and can provide high precision.

To learn more about these methods and what they can offer to increase the accuracy of for example strain distribution or deformation measurement visit the program website or read the full report here.