Growth of NGVs and comparative study of cylinder material for CNG storage

Abstract

In the present paper, the growth of Natural Gas Vehicles (NGVs) and the various pressure vessels used for storing compressed natural gas (CNG) is discussed.Also, the comparison of Von-mises stress in pressure vessels (PVs) due to internal pressure with different materials has been investigated numerically.Substantial use of natural gas is recorded as an alternative fuel, and the high-pressure storage of natural gas has resulted in using various types of cylinders in automobiles.Metal cylinders are extensively used in NGVs and are fabricated with different materials to satisfy services, safety and related factors.Metals and their alloys are often employed to make type I cylinders.It is important to calculate the failure pressure limit for a particular geometry of the tank against the yield strength of the material in case of metallic cylinders. An axisymmetric finite element model was made using the ABAQUS finite element platform to mimic the stress levels for two materials, viz steel alloy, and an aluminium alloy.The internal test pressure and geometric details of the cylinder were kept constant.The yield stress of material and numerical results have been compared.It was found that the steel alloy has outperformed the aluminium alloy for the given thickness of the cylinder.In contrast, the aluminium alloy failed to sustain the test pressure of 25 MPa.