Design and Analysis of Cng Pressure Vessel Using Natural Fibre Composites

Abstract

Bio composites comprise one or more phases derived from a biological origin; these may be reinforcements (cotton, hemp, flax, sisal, jute, and kenaf or recycled wood and paper) or organic matrices, for example, polylactic acid (PLA) and soybean resins. Use of natural fibers has been in existence for many generations, however, the discovery and subsequent commercialization of synthetics such as glass, aramids, and carbon fibers in early and mid-twentieth century resulted in the reduced preference for natural fibers in a number of applications. However recent advancement in manufacturing methods and a shift towards environmental protection shifted the focus back to biodegradable composite. This paper deals with the generation of MATLAB script files that assists the user in the design of a biodegradable composite CNG pressure vessel to operate within safe conditions. The inputs of the program are the material properties, ply strength, applied loading, cure and room temperature and fiber orientation. Classical Laminate Analysis (CLA) is a widespread theory in engineering for analyzing the stress/strain behavior of orthotropic laminates under mechanical and hygrothermal loading. CLA is an orthotropic adaptation of Kirchoff’s thin plate theory. The output of the program is extension, coupling and bending stiffness matrices, equivalent elastic constants, thermal, moisture, mechanical and total strain vector, total strains and stresses at ply Interfaces and mid planes. The calculation also predicts the minimum reserve factors with the occurrences of failure at various points in the ply interface.