Modelling of ultrasonic response from rough defects

Mike Lowe (Imperial College NDT group)

Richard Craster (Imperial College Maths dept)

Background

How to assess ultrasound reflection from rough cracks without excessive conservatism?

Purpose of project

• Develop mathematical approach to incorporate the statistics of surface roughness in the calculation of backscatter.

• Develop methodology for reliably accurate yet efficient Finite Element simulation of backscatter.

• From these develop procedure to predict backscatter from rough surface with given surface statistics; aim is for procedure to be conservative (safe) but not excessively.

Proposal

• Research streams in NDT and Maths groups at Imperial:– NDT: Gather and assess nature of roughness; develop the FE

methodology; validate mathematical model; link mathematical and FE outcomes; develop the overall procedure for practical implementation

– Maths: develop mathematical model of backscatter which incorporates statistical information and produces bounding result

• 3 years; 54 RA-months