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-ω SST 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.
DODDAMANI Hithaish
,
ABDUS Samad
,
MANABU Takao
,
SHINYA Okuhara
,
M M ASHRAFUL Alam
. Effect of Fluidic Diode on Performance of Unidirectional Impulse Turbine[J]. Journal of Thermal Science, 2024
, 33(3)
: 807
-814
.
DOI: 10.1007/s11630-024-1969-1
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