Samenvatting
The break-up behaviour of axis-switching rectangular jets was investigated numerically usingthe Local Front Reconstruction Method (LFRM). Experiments using high-speed shadowgraphy
were performed to validate the model. The study was done using nozzles with two
different aspect ratios and Reynolds numbers between 800 and 1600. In order to approximate a rectangular jet, the LFRM model was extended to account for the initialization of a super-ellipsoid geometry and a suitable velocity field. Furthermore, the performance of the hybrid formulation and pull force surface tension models was evaluated for the geometry. To characterize the jets, their break-up length, droplet diameter and axis-switching wavelength
and amplitude were analyzed. Due to time constraints, only one of the simulated jets
reached breakup. However, the break-up of the jet was found to occur within the xperimentally determined break-up region and the obtained droplet size fell in the expected range for the flow conditions. Correlations for the break-up length and axis-switching wavelength were created based on the experimental data. Despite most simulations not eaching steady state, the axis-switching behaviour of the jets was deemed stable enough for representative analysis. The simulated wavelengths were found in good accordance with the predicted values while amplitudes were significantly higher than expected. Despite the promising results, a final verdict could not be made on the validity of the model as steady state was not reached. Therefore, the study should be extended.
| Datum prijs | jan. 2023 |
|---|---|
| Originele taal | Engels |
| Begeleider | Cristina Garcia Llamas (Afstudeerdocent 1) & Vivekanand Swami (Afstudeerdocent 2) |