Heat Propagation Through Fins Made of Polymeric Materials Manufactured by 3D Printing

To investigate simultaneously both the effect of fin cross-sectional shape on heat transfer and the influence of different polymeric materials, test samples were manufactured by 3D printing in the form of bushings with attached radial fins of varying cross-sections. Through the research undertaken, the aim was to obtain information regarding the length of the fin at which a certain temperature is reached; therefore, the length that ensures efficient heat transfer to the external environment. Dedicated testing equipment was designed and built to test the thermal transfer in fins made of three different materials (polylactic acid (PLA)-based materials, i.e., standard PLA, PLA with carbon black (protopasta), and PLA with graphene (prografen)) and, respectively, with different sizes and shapes of the cross-section (circular, square, equilateral triangular, and rectangular). The experimental results were mathematically processed to develop empirical models that illustrate both the direction and the intensity of the influence of the input factors on the fin length at which a specific temperature is reached. Under certain conditions, radial components with a circular cross-sectional area of 20 mm² showed significant differences depending on the polymer type. For the polylactic acid material, this length was 42% higher than for prografen and 25% higher than for protopasta.