Project GRAID and computational fluid dynamics!

Thinking about how the robot affects flow

By introducing the GRAID robot into our transmission assets, we have the potential in inhibit flow of gas around the site; knowing the impact that this allows our control centre to be informed and ensure minimal disruption to the network as a whole. A method of analytically investigating this is through use of computational fluid dynamics (CFD) software which takes the input parameters of flow speed, pressure and gas characteristics and is modelled with the desired environment, a 750mm pipe with the robot placed inside and calculates how a flow behaves.

CFD investigation showed negligible long term effects of the introduction of the robot, with flow normalising again beyond 15m. Interestingly, it was found that in the areas around the robot itself, flow speeds almost doubled, with the robot effectively acting as a nozzle, highlighting the need for a good dynamic response from the NDT arm to keep it stable when operating.