Temporal evolution of the near wake of an impulsively started parachute canopy

H. Johari, K. Stein, Tayfun E. Tezduyar

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

The flow field in the near wake of an impulsively started rigid impermeable parachute canopy was studied computationally by a finite element scheme. The separated shear layer surrounding the canopy created a starting vortex ring. As time evolved, flow instabilities caused the vortex ring to become convoluted and eventually led to the breakup of the ring. This phase of the flow took a time of about 16D/U, where D is the effective projected diameter of the canopy and U is the freestream velocity. After the initial phase, the flow went through a transition phase where the drag reached a local peak prior to settling into its steady state. In the steady state phase, the drag and base pressure coefficient of the canopy were nearly constant. The computed drag coefficient matched very well against experimental data. The time to reach the steady state was 45D/U. During the steady state phase, a complex vortex shedding pattern was observed in the near wake despite the nearly constant drag coefficient.

Original languageEnglish
Title of host publicationFluids 2000 Conference and Exhibit
Publication statusPublished - 2000
Externally publishedYes
EventFluids 2000 Conference and Exhibit - Denver, CO, United States
Duration: 2000 Jun 192000 Jun 22

Other

OtherFluids 2000 Conference and Exhibit
CountryUnited States
CityDenver, CO
Period00/6/1900/6/22

Fingerprint

Parachutes
Drag coefficient
Drag
Vortex flow
Vortex shedding
Flow fields

ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes
  • Energy Engineering and Power Technology
  • Aerospace Engineering
  • Mechanical Engineering

Cite this

Johari, H., Stein, K., & Tezduyar, T. E. (2000). Temporal evolution of the near wake of an impulsively started parachute canopy. In Fluids 2000 Conference and Exhibit

Temporal evolution of the near wake of an impulsively started parachute canopy. / Johari, H.; Stein, K.; Tezduyar, Tayfun E.

Fluids 2000 Conference and Exhibit. 2000.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Johari, H, Stein, K & Tezduyar, TE 2000, Temporal evolution of the near wake of an impulsively started parachute canopy. in Fluids 2000 Conference and Exhibit. Fluids 2000 Conference and Exhibit, Denver, CO, United States, 00/6/19.
Johari H, Stein K, Tezduyar TE. Temporal evolution of the near wake of an impulsively started parachute canopy. In Fluids 2000 Conference and Exhibit. 2000
Johari, H. ; Stein, K. ; Tezduyar, Tayfun E. / Temporal evolution of the near wake of an impulsively started parachute canopy. Fluids 2000 Conference and Exhibit. 2000.
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