Monitoring Strain in High Temperature Steam Pipes using Digital Speckle Photogrammetry Techniques

摘要

Strain measurement techniques should be valid, accurate and reliable in order for the results obtained to be used. Digital Speckle Photogrammetry (DSP) is proving to be a very useful technique for examining, in laboratory conditions, the distribution of strain about cracks and other faults in stressed specimens. The DSP method has good potential for use in monitoring parts of electrical power station plants, blades of wind turbine power generators and for other monitoring requirements. On the other hand, there are many installation problems to be overcome. For example, there is the need to have regard for the hostile environment in steam generating plants and the demanding weather conditions to which wind turbine blades are subjected. A significant advantage of the Digital Speckle Photogrammetry technique is the fact that the collection of outputs from individual DSP sensors for continuous remote monitoring is possible. However, DSP measurements can also be useful each time a plant is shut down. This is to complement data from existing monitoring methods that are used at present time.