INVESTIGATION OF MECHANICAL PROPERTIES OF DOUM PALM LEAF STALK FIBRE (HYPHAENE THEBAICA) REINFORCED POLYMER COMPOSITES FOR AEROFOIL APPLICATION

The National Advisory Committee for Aeronautics (NACA) Aerofoil shapes have been used over the years as wing and tail sections for general aviation, as well as propeller, turbine blades, compressor blades, and helicopter rotors. The aircraft performance is highly affected by low lift force, relatively high drag force, high pitching moment and poor stall behavior, contributing to increased fuel consumption and loss of control leading to accidents in airplanes. The combinations of these forces on the aerofoils are responsible for the take-off and landing performance of airplanes. This study addresses the inefficiencies of conventional aerospace materials, which lead to these aerodynamic deficiencies. The problem of heavy-weight materials in the aerospace industry is becoming increasingly worrisome. Materials with excessive weight, such as steel, magnesium alloys, titanium, and some composites with fillers, can negatively affect an airplane’s aerodynamic performance. Many researchers have aimed to overcome this deficiency by modifying the materials, shape, and size of the aerofoils, yielding promising results that require further improvement in general aerodynamic performance. In this study, composites were produced using Doum palm leaf stalk fibre, epoxy resin, and Calcium Sulphate Hemihydrate 〖(CaSO〗_4 1/2 〖.H〗_2 O) via the hand lay-up method. Single fibre tests were conducted for four specimens (samples 1 to 4). Six composite specimens (A to F) were conducted in different formulations and tested for tensile strength, flexural strength and density. Sample F (25.85 MPa) demonstrated the highest tensile strength and the flexural strength results showed that Sample F (50.80 MPa), with the highest fibre content. The single fibre pull-out tests indicated that the average maximum load at failure for Doum palm fibre was 8.55 N, with an embedded length of 8.75 mm and a diameter of 252 μm, showing mechanical properties suitable for engineering applications. Density tests showed that the composite densities ranged from 0.815 to 0.948 g/cm³, with the highest density observed in sample B and exhibited the highest density at 0.948 g/cm³, making it suitable for lightweight applications. The study recommends adopting these Doum palm leaf stalk fibre composites in aerospace and engineering fields due to their improved performance.