On dynamics of acoustically driven bistable fluidic vvalves
The dynamics of an actively controlled fluidic diverter with novel actuation method are presented. This bistable fluidic valve is based on the Coanda effect and is able to switch the main flow solely by means of acoustic excitation. The switching is explained through a combination of experiments and...
| Main Authors: | , , |
|---|---|
| Format: | Journal article |
| Published: |
American Society of Mechanical Engineers
2018
|
| _version_ | 1797100618993631232 |
|---|---|
| author | Mair, M Bacic, M Ireland, P |
| author_facet | Mair, M Bacic, M Ireland, P |
| author_sort | Mair, M |
| collection | OXFORD |
| description | The dynamics of an actively controlled fluidic diverter with novel actuation method are presented. This bistable fluidic valve is based on the Coanda effect and is able to switch the main flow solely by means of acoustic excitation. The switching is explained through a combination of experiments and large eddy simulations (LES). The switching time and minimum energy required are characterized for a range of pressure ratios, acoustic excitation frequencies, and input powers. It is shown that the switching mechanism depends on the excitation of natural instabilities inside the free shear layer. An enhanced roll-up of vortices at the excitation frequency increases the rate of entrainment and results in a transverse pressure gradient sufficient to counteract the Coanda effect leading to jet detachment and switching. |
| first_indexed | 2024-03-07T05:40:07Z |
| format | Journal article |
| id | oxford-uuid:e549233e-891e-4986-835c-7916528a7f90 |
| institution | University of Oxford |
| last_indexed | 2024-03-07T05:40:07Z |
| publishDate | 2018 |
| publisher | American Society of Mechanical Engineers |
| record_format | dspace |
| spelling | oxford-uuid:e549233e-891e-4986-835c-7916528a7f902022-03-27T10:22:52ZOn dynamics of acoustically driven bistable fluidic vvalvesJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:e549233e-891e-4986-835c-7916528a7f90Symplectic Elements at OxfordAmerican Society of Mechanical Engineers2018Mair, MBacic, MIreland, PThe dynamics of an actively controlled fluidic diverter with novel actuation method are presented. This bistable fluidic valve is based on the Coanda effect and is able to switch the main flow solely by means of acoustic excitation. The switching is explained through a combination of experiments and large eddy simulations (LES). The switching time and minimum energy required are characterized for a range of pressure ratios, acoustic excitation frequencies, and input powers. It is shown that the switching mechanism depends on the excitation of natural instabilities inside the free shear layer. An enhanced roll-up of vortices at the excitation frequency increases the rate of entrainment and results in a transverse pressure gradient sufficient to counteract the Coanda effect leading to jet detachment and switching. |
| spellingShingle | Mair, M Bacic, M Ireland, P On dynamics of acoustically driven bistable fluidic vvalves |
| title | On dynamics of acoustically driven bistable fluidic vvalves |
| title_full | On dynamics of acoustically driven bistable fluidic vvalves |
| title_fullStr | On dynamics of acoustically driven bistable fluidic vvalves |
| title_full_unstemmed | On dynamics of acoustically driven bistable fluidic vvalves |
| title_short | On dynamics of acoustically driven bistable fluidic vvalves |
| title_sort | on dynamics of acoustically driven bistable fluidic vvalves |
| work_keys_str_mv | AT mairm ondynamicsofacousticallydrivenbistablefluidicvvalves AT bacicm ondynamicsofacousticallydrivenbistablefluidicvvalves AT irelandp ondynamicsofacousticallydrivenbistablefluidicvvalves |