A comparative analysis of flow characteristics inside a closed-ended micro-shock tube using both pressure-based and density-based algorithms

This work intends to compare the pressure-based coupled algorithm and the density-based algorithm for the two-dimensional high speed gas-particle two-phase compressible flow in the closed-ends micro-shock tube. The micro-shock tube is employed in the medical sector for the drug delivery without needle. The mass along with momentum transfer equations for compressible flow, together with the computational approach, are provided. These solvers are used to perform the transient simulation. The pressure-based algorithm offers the versatility to address flow issues using either a coupled or a segregated method. Choosing the coupled technique over the non-coupled or segregated approach has some benefits. In particular, the linked scheme outperforms segregated solution techniques and provides a reliable and effective solution for steady-state flows. The den sity-based and pressure-based segregated methods using SIMPLE-type pressure-velocity coupling is replaced by this pressure-based coupled technique. Using the coupled approach becomes essential when dealing with poor mesh quality or when using high time steps in the case of transient flows. The schlieren and vorticity contours were obtained to analyze and compared for both the solvers to determine their efficacy to capture the shock waves and fluid element rotation. This is the major gap and novelty found through the literature survey for such kind of problem. The pressure histories and Mach no. were recorded for both the solvers. The result obtained through these solvers show that though the pressure-based algorithm is capable for handling high speed compressible flow problem but when it comes about the CPU time as well as the accuracy of the result, the density-based solver is more reliable for this problem.