EVALUATION OF DBF AND DBA METHODS FOR HEAD GEOMETRIES IN MULTI-FUNCTIONAL PMMA HYPERBARIC CHAMBERS
DOI:
https://doi.org/10.55766/sujst11258Keywords:
HBOT, ASME-PVHO, PMMA, Finite Element MethodAbstract
Pressure vessels are widely used in various industrial and commercial fields. These include diving cylinders, recompression chambers, and hyperbaric oxygen therapy chambers. Hyperbaric chambers are a special group of pressure vessels that operate at a specific pressure for treatment. In this study, analyses were carried out on the design of a cylindrical hyperbaric test chamber to be used for devices such as submarine equipment or a bedside monitors that require performance tests under pressure, using DBF and DBA methods. The body and head thicknesses calculated using the DBF method in accordance with ASME PVHO-1 standards were revised and reduced within the constraints and rules specified in the formulas. Thickness analyses of the chamber with a diameter of 800 mm and a length of 1500 mm were re-evaluated using the DBA method for two different head geometries (spherical and hemispherical), considering the safety conditions accepted in ASME PVHO-1 standards. PMMA (Polymethyl methacrylate) was chosen as the cabin material for its lightweight properties. The chamber was analysed for two different pressure values: 10 bar operating pressure (MAWP) and 16.5 bar test pressure (MAP). The analyses resulted in beneficial outcomes in terms of both manufacturing ease and cost. The hemispherical head geometry demonstrated superior performance than the spherical head geometry in terms of stress distribution, resistance to test pressure, geometric complexity, and safety factor. Consequently, the thickness values, which have been proven to be safe through analysis, can be used instead of the numerically obtained results.
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