Abstract
The peeling process requires the prior heating of round green-wood to a temperature in the range of 50 to 90 °C. This treatment is necessary to increase wood deformability, to lighten lathe checking into veneers and to reduce cutting forces. It is usually done by immersion in hot water or by steam treatment. However it presents many disadvantages among which duration of treatment (12 to 72 hours), washing out of polyphenolic extractives which cause water pollution and can affect wood’s natural durability, increasing bolt end splitting threatening bolt cohesion.The goal of this PhD thesis is to develop a heating system embedded on the peeling lathe to circumvent many of these disadvantages. The infrared technology appears to be the most promising solution because of the power it offers and of the easiness of integration on the machine. This new technology using radiant energy to heat green-wood prior to peeling would be a major innovation for the industries involved in the production of plywood, Laminated Veneer Lumber (LVL), etc.The plan to achieve this goal requires to:- Elaborate a model of infrared heat transfer in green wood while peeling-Investigate the thermal and optical (in terms of infrared penetration) behaviour of green wood to feed the model-Validate the model with experimental peeling tests This PhD thesis would be prepared in co-tutelle between Arts & Métiers Cluny, France and Aalto University, Helsinki, Finland.