Category: Transient Plane Source
Author(s): Bashir Suleiman
Abstract: Composite materials are materials made of reinforcing substances that are set in a matrix of polymers, ceramics or metals. This experiment measured the thermal conductivity of wood and ceramics, and explored the factors that influence the thermal conductivity. The Transient Plane Source (TPS) method was used because test times are relatively short compared to steady state techniques, and transient methods are not limited by the size, shape, or state of the samples. For this method, the samples surrounded the sensor, and then the sensor sent a pulse of heat through the sample. As this occurred over a pre-determined period, the sensor simultaneously recorded how long it took for the sample’s temperature to rise. Wood is anisotropic, so it was found that thermal conductivity was higher when the test was performed parallel to the grain, rather than across the grain, possibly due to the arrangement of cellulose. According to the results, porosity of wood seemed to be the main factor that affected its thermal conductivity. The thermal conductivity for the ceramic composites seemed to depend on the mineralogy, the structures of the reinforcing materials, and the range of differences among the conductivities of the constituents. The conductivities of the materials that make up the composites can be estimated without the use of the TPS method. Knowing the thermal conductivity of composite materials such as wood and ceramics can help to monitor minute changes within structures and therefore increase their stability in the future.
Reference: In: Advances in Composites Materials- Ecodesign and Analysis (2011) 625-642