Designing and optimization of pressurizing gas diffusers in cryogenic methane tank: a technical approach

This paper presents a methodology for the sizing and subsequent optimization of the inert pressurizing gas injection element in a cryogenic tank. The study consists of several steps, starting from the operating conditions, by means of a 0-dimensional model, a comparison is first made between the two main injection configurations, axial and radial. First-degree dimensions are obtained through the definition of an efficiency parameter that is based on the comparison of the heat flows dissipated by the pressurizer with the work carried out by the same to empty the tank. Subsequent fluid dynamics analysis phases then allow us to identify the optimal geometry and dimensions for correct operation. The paper then ends with the attempt to optimize the chosen geometry, evaluating the distribution of the outlet flow rates and the pressure drops and evaluating the introduction of elements that allow an increase in fluid dynamic resistance and therefore a further slowing down of the flow.