- PII
- 10.31857/S2686740023010029-1
- DOI
- 10.31857/S2686740023010029
- Publication type
- Status
- Published
- Authors
- Volume/ Edition
- Volume 509 / Issue number 1
- Pages
- 28-38
- Abstract
- It is known that in wall-bounded flows, along with the growth of instability modes, the non-modal (algebraic) mechanism of linear growth plays an important role. In open flows, including submerged jets, the non-modal growth mechanism is theoretically studied only in the last decade; this mechanism has not yet been identified in experiments. In the present work, experiments on excitation of a non-modal “lift-up” growth mechanism are conducted. Special wavy structures (deflectors) are introduced into a laminar submerged jet of circular cross section, which excites a roller-like transverse movement. The data obtained unambiguously identify the non-modal “lift-up” growth of introduced disturbances. The development of perturbations in the experiment qualitatively corresponds to the theoretically calculated optimal perturbations. The features of the transition to turbulence caused by non-modal growth are considered.
- Keywords
- затопленная струя оптимальные возмущения немодальный рост ламинарно-турбулентный переход
- Date of publication
- 16.09.2025
- Year of publication
- 2025
- Number of purchasers
- 0
- Views
- 12
References
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