Heat Conduction Modeling & Experimental Verification on Thermal Properties of Teak Wood Dust Filled Epoxy Composites Dr. Ramesh Chandra Mohapatra Professor& Head, Mechanical Engineering Department, Government College of Engineering Keonjhar-758002, A Constituent College of Biju Patnaik University & Technology, Rourkela,Odisha, India Abstract: The aim of the experiment was to prepare the specimens of 200μm filler size applying a technique known as hand-lay-up technique to test the thermal conductivity of TWDPC with the help of Forced convection apparatus in longitudinal direction at different volume fractions. A mathematical heat conduction model was developed based on the law of minimal thermal resistance & equal law of specific thermal conductivity. The results obtained from this model were compared with the experimental result.It was found that the proposed model was very close to the experimental values of effective thermal conductivity. The slight deviation between these two was due toimproper molding (presence of voids &pores within the composites) , thermal resistance at the filler-matrix interface& the assumptions taken for the development of heat conduction model. From the experimental work, it was observed thatwhen the volume fraction of the filler (TWD) increases the effective thermal conductivity of epoxy composites decreases. It indicates towards the good insulation properties of the developed composites. Keywords: Heat conduction model, epoxy-teak wood dust composite, Forced convection apparatus, thermal conductivity,hand-lay-up technique. 1. Introduction Natural fibres are fibres that are derived from animals or plants. They are environment friendly & easily available in nature.The polymer composites made from natural fibers are light, strong, cheap, nonabrasive, biodegradable, sustainable& are more environment friendly.Now a daymany industries are showing interest to produce their products with natural fibre reinforced polymer composites (NFRPC) because of the above properties. The improvement of insulating properties of natural fibre reinforced polymer composites can be determined by measuring their thermal properties.. Russel [1] & Maxwell [2]’s theoretical models have been widely used for predicting thermal conductivity of multiphase composites. Maclean [3], Kolman [4], Wikes [5], &Kamke [6] reviewed the empirical equations for predicting the thermal conductivity of wood &wood based panel products.Suleiman et al [7] verified that thermal conductivity of wood in longitudinal direction was about 1.5 to 1.6 times more than transverse direction in the temperature range of 20-100 0 C. Zeng et al [8], Chang et al [9], Liang& Liu [10], Agrawal &Satapathy [11], Devireddy& Biswas [12], Gao et al [13] & Gao et al [16] used the series-parallel thermal resistance model to predict the effective thermal conductivity. Mohapatra et al [14] determined the thermal conductivity of PWD filled polymer composite at different volume fractions in longitudinal direction using Forced convection apparatus. Mohapatra [15] developed an experimental approach to investigate thermal conductivity of rice husk filled epoxy composites in transverse direction using Lee’s apparatus. Considering all these literature reviews, the composites of epoxy with varying contents of TWD & heat conduction model using minimal law of thermal conductivity & equal law of specific equivalent thermal conductivity have been developed in the present work. Results obtained from the proposed model were compared with the results obtained from experiment& various theoretical models. 2. Development of Heat conduction model The heat conduction model is developed based on the basis of minimal thermal resistance & equal law of specific equivalent thermal conductivity as shown in figure 1. The law of minimal thermal resistance is required to combine the heat resistance of matrix as well as filler to get the heat resistance of whole composite. The equal law of specific equivalent thermal conductivity is applied to predict the effective thermal conductivity of the composite. A cube with side H & a single spherical particle (filler) of radius r at the centre was taken as a unit for the understudy. In the present work, the heat transfer of the unit cell is in y- direction. The heat can be transferred in three main ways conduction, convection & radiation. Since, the thermal conductivity of the materials are under steady state, hence the amount of thermal radiation is very small & neglected. On the other hand the size of the spherical particles & the pores between the elements is also small. Hence, convective heat transfer is not considered in the modeling process. On the basis of the above concepts, the following assumptions are made to describe the mathematical analysis of heat transfer in composite materials. (a) filler particle assumed to be spherical (b) both the matrix & filler materials are homogenous & isotropic (c) the filler & the matrix are in good contact i.e the lamina is free from voids (d) heat conduction is one dimensional i.e in y direction (the flow of heat is along the axis i.e longitudinal direction) & (e) the temperature distribution along Strad Research DOI: 10.37896/sr10.7/052 ISSN: 0039-2049 VOLUME 10, ISSUE 7, 2023 http://stradresearch.org/ 523