In oil extraction from the North Sea, one problem is the build up of wax in undersea pipelines. When the oil temperature is 60–70°C, all the wax is dissolved, but as the temperature drops below 35–40°C, wax solidifies onto the walls of the pipe, restricting the flow. Norsk Hydro wish to understand the physical processes involved, and to understand some experimental results on wax deposition. The Study Group showed that modelling the problem using kinetic undercooling and shear-induced diffusion gave results in broad agreement with the experiments.

Problem presented by
Svenn Anton Halvorsen, on behalf of Norsk Hydro ASA

Study Group contributors
Clare Bailey (University of Loughborough)
Christopher Bell (University of Oxford)
Richard Booth (University of Oxford)
Rebecca Carter (University of Oxford)
Sunny Chiu-Webster (DAMTP)
Rosemary Dyson (University of Oxford)
Jonathan Evans (University of Bath)
Heike Gramberg (University of Oxford)
Harald Hanche-Olsen (NTNU)
Gareth Jones (University of Oxford)
Rachel Levy (Duke University)
Pamela Lisseter (University of Surrey)
Rafael Morones (ITAM)
Andrejs Novikovs (University of Oxford)
Hilary Ockendon (University of Oxford)
John Ockendon (University of Oxford)
Giles Richardson (University of Nottingham)
Warren Smith (University of Birmingham)
John Stockie (Simon Fraser University)
Heather Tewkesbury (Industrial Mathematics KTN)
Rein Van Der Hout (University of Leiden)
Dominic Vella (DAMTP)
Hannah Woollard (University of Nottingham)

Study Group report
To obtain a copy of the report for this project, written by Rebecca Carter, Jonathan Evans and Giles Richardson, please contact David Allwright at the Industrial Mathematics KTN.