A pair of unidirectional turbines(UT)can operate in oscillatory airflow without additional units.However,this arrangement suffers from poor flow rectification.A fluidic diode(FD)offers variable hydrodynamic resistance...A pair of unidirectional turbines(UT)can operate in oscillatory airflow without additional units.However,this arrangement suffers from poor flow rectification.A fluidic diode(FD)offers variable hydrodynamic resistance based on the flow direction,and this can be coupled with UT to improve flow rectification.In this work,a numerical investigation on the effect of FD with UT is presented using the commercial fluid dynamics software ANSYS Fluent 16.1 with k-ωSST turbulence closure model.Periodic domains of UT and FD are numerically validated individually with experimental results.Later,both are coupled to obtain the combined effect,and these results are compared with the analytical approach.It was observed that coupling FD with UT improved the unit's performance at the lower flow coefficient(<1),but its performance decreased as the flow coefficient increased.Due to the diode's presence,fluid leaving the turbine experiences higher resistance at a higher flow coefficient,which decreases the overall performance of the combined unit.展开更多
基金performed as a Grant-in-Aid for Early-Career Scientists(No.22K14434)supported by the Japan Society for the Promotion of Science(JSPS)JSPS for their financial help in conducting this studyⅡT Madras for the computational facility and financial help to present part of the work in AJWTF-2020。
文摘A pair of unidirectional turbines(UT)can operate in oscillatory airflow without additional units.However,this arrangement suffers from poor flow rectification.A fluidic diode(FD)offers variable hydrodynamic resistance based on the flow direction,and this can be coupled with UT to improve flow rectification.In this work,a numerical investigation on the effect of FD with UT is presented using the commercial fluid dynamics software ANSYS Fluent 16.1 with k-ωSST turbulence closure model.Periodic domains of UT and FD are numerically validated individually with experimental results.Later,both are coupled to obtain the combined effect,and these results are compared with the analytical approach.It was observed that coupling FD with UT improved the unit's performance at the lower flow coefficient(<1),but its performance decreased as the flow coefficient increased.Due to the diode's presence,fluid leaving the turbine experiences higher resistance at a higher flow coefficient,which decreases the overall performance of the combined unit.
