The Importance Of Conductivity Profiles - 884 Words

As discussed at the start of this section, it has not been possible to manufacture an experimental sample with a well defined conductivity gradient during the course of this work. Oxidised bricks created using a thermal oxidation furnace were intended to be examined however difficulties in constructing a suitable furnace have meant that these were not available during this project. An alternative methodology based on the work of Brocklehurst [94] has been attempted to assess the ability of the reconstruction algorithm to calculate conductivity profiles from experimental data. However, first it has been necessary to determine the suitability of a lattice of holes to act as an analogue for weight-loss (equivalently a reduction in bulk†¦show more content†¦This is in spite of the fact that each of the three simulations must necessarily be solved on a di↠µerent FE mesh, which can cause significant errors (as was seen in the cracking work,  § 4.2). Based on this, the assumption that a lattice of drilled holes can be used to represent a brick with an e↠µective conductivity drop appears valid. The exact relationship between the lattice spacing of the holes and the drop in conductivity this induces is yet to be established and further models with di↠µerent lattice spacings would be required to establish this. The simulations conducted so far suggest that the lattice used on the bore surface of the brick (with a lattice spacing of 14.13 mm) gives a conductivity drop of approximately 14% whilst the lattice on the outer brick surface (with a spacing of 23.83 mm) gives approximately a 6% reduction. For further applications of this work an understanding of the relationship between these models and experimental data would be necessary as a physical network of holes may not have precisely the same e↠µect on the eddy current distribution as that predicted by FE simulation. In order to estimate the conductivity profile of the brick with a lattice of holes, the approximate conductivity reduction for the bore and peripheral lattices was calculated from the FE modelling of  § 6.2.2. This was found to be a 14% conductivity drop for the bore lattice and a 6% drop for the periphery lattice. TheseShow MoreRelatedModelling For Optimisation Of Coffee Rasting1238 Words   |  5 Pagescoffee roasting using mathematical models. 2. To predict the profile of moisture and temperature of the single bean during roasting. Understand research outputs: The main research outputs are: 1. Single-bean temperature profile during roasting (at the center). 2. Average moisture content profile during roasting. 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