Abstract

Dry powder inhaler (DPI) is one of many pulmonary drug delivery systems that are commonly prescribed for the treatment of a variety of diseases. However, the efficiency of the current DPI is limited as a variable, and low portions of the dose reach the deep lungs. The complexity of a DPI platform that involves multiple physics domains, including aerodynamics and solid mechanics, is a significant obstacle to improving its performance and efficiency. Numerical simulation such as computational fluid dynamics (CFD), discrete element method, and finite element analysis, is beneficial for investigating the underlying aerosolization mechanisms and evaluating DPI design. Visualization of fluid flow and particle trajectory, particle interaction, and parametric optimization is enabled by numerical simulation. It opens the opportunities for computer-aided designs of DPI systems in formulation development, device development, and observation of patient factors on particle deposition and targeting aerosol to a particular area of the lungs. This chapter reviews the basic principles of CFD and related physics and the application of numerical simulation to study fluid dynamics in DPIs. The limitation and future trends of numerical simulations in aerosol delivery system research are also discussed.