This study developed a model that used a transient plane source (TPS) sensor to measure the specific heat capacity of anisotropic materials. The underside of a sample holder with a diameter of 20 mm, and a height of 5 mm was attached to a Kapton TPS sensor. During measurements, the sample holder was hung inside a steel tube at atmospheric pressure. Results showed that the model underestimated the heat capacity, which suggests ...
The Transient Plane Source (TPS) Technique measures the thermal conductivity, thermal diffusivity, and specific heat of solids and liquids. An electrically conducting double spiral nickel sensor pulses a current through a sample which increases its temperature, while simultaneously recording the length of time it took for the sample to heat up. This study, researchers tested the thermal properties of various materials and determined that anisotropy must be considered when these ...
Using a solid hot stretching technique, highly-oriented polyoxymethyelen (POM)/multi-walled carbon nanotubes (MWCNTs) composites were created. Thermal properties were analyzed both in the stretched and through-plane directions. Researchers found that by increasing the draw ratio, to as high as 900%, the thermal conductivity of the composite has improved in the stretching direction, when compared to the material prior to this process. Researchers also determined that the thermal conductivity of the MWCNTs ...
With the use of multiple thermal instruments, the thermal conductivity (lambda) of fibrous insulations was measured in the plane direction. In this study, a method was put forth the estimate thermal conductivity. This method assumed that the thermal conductivity of the anisotropic material was equivalent to that of an isotropic material with identical bulk density and specific heat. This novel method displays the thermal conductivity of the anisotropic material as √(...
The thermal conductivity and thermal diffusivity of SRP (sisal-reinforced polyethylene), GRP (glass-reinforced polyethylene), and GSRP (sisal/glass hybrid fibre-reinforced polyethylene) were tested from 120 to 350K. Results showed variances in thermal conductivity values with varying temperatures in materials containing different orientations of sisal fibres. Due to the anisotropic nature of the SRP fibre, there is a difference in the thermal conductivity readings from the parallel to the perpendicular direction. The GRP ...
