Research team: Ryan van Herel, Dr Nurzhan Nursultanov, Dr Bill Heffernan and Dr Justin J Nijdam (not pictured)
Dr Nurzhan Nursultanov, an EPECentre Research Engineer, and his research associates, have had their paper “Computational calculation of temperature and electrical resistance to control Joule heating of green Pinus radiata logs published in Applied Thermal Engineering. This article presents some of the outcomes of the Joule Log Heating (JLH) project. The JLH technology is an ozone friendly alternative to methyl bromide fumigation. More information about Joule Log Heating.
The paper describes a computational model employed to control the Joule heating of twenty green export size Pinus radiata logs from trees grown in the Canterbury region of New Zealand. The heating process was modelled using custom-built one-dimensional computational software based on the finite volume method (FVM). The proposed control method utilized the logs’ experimental bulk electrical resistance as a feedback variable during the Joule heating operation. As wood resistance is temperature dependent, comparing the experimental and predicted resistance values allowed an indirect determination of the actual wood temperature. The model accurately predicted the log resistance and the final log temperature, with an error of 6% and 5%, respectively. The limitations and further improvements to the model are discussed in the paper.
In conjunction with previously published papers, including the joint work by Scion and the EPECentre, the process has now been scientifically shown to be a technically coherent and proven solution to heating logs for phytosanitary, and potentially also veneer peeling, applications.
