Computational Modeling and Analysis of Turbulent Flows in the Humidification Unit of the Continuous Positive Airways Pressure Device

Abstract

In this paper, an investigation into the dynamics flow behaviour of a humidifier unit is carried out using the numerical simulation method. The Computational Aeroacoustics (CAA) with a hybrid approach is conducted in the ANSYS software environment. The CFD simulations were used to investigate the internal flow behaviours of the humification fluid model. The predicted results have shown the internal flow characteristics combined with scatters, circulations, and separation behaviours. These behaviours are due to the installation of a baffle unit inside the humification unit. Turbulent and pressure fluctuations were used to predict the noise level generated within the system. The predicted results are compared with the experimental results for validation. The comparison shows the predicted results agreed with the experimental result with some differences in frequency analysis. In summary, the numerical model was developed for the CPAP humidifier unit to study the internal flow behaviours and the potential noise source location. The predicted results have explained and identified some locations of interest. These findings were used as guidelines to optimise and further develop to improve the future product. It also concludes that the CAA approach can be considered as a potential cost-effective tool in the early product development process for a better product design.