Dr John Abrahamson
Associate Professor (Retired)
ME(Chem), PhD(Chem), FRSNZ, CEng, MIChemE(UK)
Department of Chemical and Process Engineering
University of Canterbury
Private Bag 4800
John Abrahamson has recently collaborated with astrophysicist John Marshall from SETI, NASA in California on electrostatic dipoles on solid particles, materials scientist Graham Hubler from Naval Research Lab in Washington DC on ball lightning, and spent two periods (in 2003 and 2004) with thermodynamicist Dendy Sloan at the Colorado School of Mines, US, modelling the formation and aggregation of natural gas hydrate particles into pipeline slugs (often an important safety issue with natural gas pipelines).
He spent leave at AEA Technology, Harwell, UK, modelling cyclone dust collectors and measuring granular particle residence times through cyclones, helpful for drying and chemical reaction design.
He has consulted in the gas cleaning area for a large number of NZ firms. Recent industrial projects include the study of caking of urea granules, control of wood fibre emissions and soap emissions connected with droplet escape. He has been involved in various aspects of secondary school science. He has been Associate Dean for the Faculty of Engineering, and Chairman of the IPENZ National Schools Liaison Committee.
His work on ball lightning has been written about in popular science journals such as BBC sci/tech online, Science, Discovery, New Scientist, and his early work (1978) on nanotubes has been mentioned in Nature. He is listed in Who’s Who in Science and Engineering, Marquis Who’sWho, NJ, US.
Early work here in the 1970's on carbon nanotubes has been extended. A continuous arc process has been designed developed and patented for making nanotubes more economically than at present. A patent has been applied for. Research students are especially sought for this project.
Recent work on ball lightning (a long-lived luminous object seen sometimes during thunderstorms)
- A theory was published in Nature in 2000 explaining ball lightning as a collection of nanospheres of metal, resulting from a lightning strike on soil. The fine particles gradually oxidise in the air, and radiate over a lifetime of seconds or minutes. This theory was elaborated and extended to strikes on metal structures in 2002, in Phil. Trans. Roy. Soc. A Lond.. We are currently testing the theory in the laboratory.
- Worldwide collection of observations of ball lightning, in collaboration with Moscow University.
Particle Aggregation, Motion of Particles in Vortex and Separated Flow
Areas of study include flows in the vortex breakdowns of cyclones, flow modelling, pressure drop prediction, the influence of cyclone entry geometry and measurement of residence times of solids passing through cyclones, notably those used for collection of drying particles. Recent work with a NASA physicist hasdescribed for the first time the role of permanent electric dipoles on particles in bringing about their aggregation. This has many implications in industry, as well as in cosmology (the early formation stages of the planets from dust).
To gain a better understanding of the causes of avalanches, research has been carried out on the measurement and statistical description of shear strengths under slabs, shear zone propagation theory, mass transport. and crystal metamorphosis in oscillating air flows. Current work is aimed at detection, by radar, of cracks in snow.
Urea Reactions in a Storage Heap
Ammonia evolution in urea storage heaps has been modelled in an effort to control ammonia emissions. A possible link has been found with the caking of urea. This includes solid deposit on urea by the reaction of evolved ammonia with atmospheric carbon dioxide.
Hii, M.J.W., Abrahamson, J., Jordan, P.J. Modelling of air flow and pollen collection by a single kiwifruit flower under wind and an air jet. Third International Conf. on CFD in the Minerals & Process Indust., CSIRO, Melbourne, Aust. 10-12 Dec., 2003.
Abrahamson, J. Ball lightning from atmospheric discharges via metal nanosphere oxidation: from soils, wood or metals. Phil. Trans. Roy. Soc. Lond. A. v360, no. 1790, 2002: 61-88.
Bychkov, A.V., Bychkov, V.L., Abrahamson, J. On the energy characteristics of ball lightning. Phil. Trans. Roy. Soc. Lond. A . v360, no. 1790, 2002: 97-106.
Abrahamson, J., Bychkov, A.V., Bychkov, V.L. Recently reported sightings of ball lightning: observations collected by correspondence and Russian and Ukrainian sightings. Phil. Trans. Roy. Soc. Lond. A . v360, no. 1790, 2002: 11-35.
Abrahamson, J., Marshall, J. Permanent electric dipoles on gas-suspended particles and the production of filamentary aggregates. J. Electrostatics . v55, no.1, 2002: 43-63.
Abrahamson , J., Jones, R., Lau, A., Reveley, S. Influence of entry duct bends on the performance of return-flow cyclone dust collectors. Powder Technology . v123, no.2-3, 2002: 126-137.
John Abrahamson and James Dinniss (2000) Ball lightning caused by oxidation of nanoparticle networks from normal lightning strikes on soil. Nature Vol. 403, 519-521. (see also the News and Views on pp 487-488, same issue).
John Abrahamson, Peter G. Wiles, Brian L. Rhoades (1999) Structure of carbon fibres found on carbon arc anodes Carbon Vol. 37, 1873-1874, reprinted paper presented at the 14th Biennial Conference on Carbon, June 25-29, 1979, The Pennsylvania State University, University Park, Pennsylvania, USA, with an editorial in the same issue mentioning the possible historical significance of the paper.
Kemp, I. C., Frankum, D. P., Abrahamson, J and Saruchera, T. (1998) Solids residence time and drying in cyclones. In Proceedings of the 11th International Drying Conference, Thessilonika, Greece, Aug. 1998, vol. A,581-588.
Saruchera, T and Abrahamson, J. (1997) Residence time of granular particles through a cyclone - analysis using moments, Laplace Transform and least squares methods. Proceedings of the 1997 Chemeca conference, Sept. 1997, Rotorua, NZ., 201-213.
Abrahamson, J. and Earl, W.B. (1993) Improvement experiments - promoting active planning in engineering laboratories. Proceedings of Australasian Association for Engineering Education Conference, Auckland, December 1993.