The 2D lumped wake vortex method applied to unsteady flapping

David J. Talarico, Aaron Mazzeo, Mitsunori Denda

Research output: Contribution to journalArticlepeer-review


Purpose: Advancements in aerospace technologies, which rely on unsteady fluid dynamics, are being hindered by a lack of easy to use, computationally efficient unsteady computational fluid dynamics (CFD) software. Existing CFD platforms are capable of handling unsteady flapping, but the time, money and expertise required to run even a basic flapping simulation make design iteration and optimization prohibitively expensive for the average researcher. Design/methodology/approach: In the present paper, a remedy to model the effects of viscosity is introduced to the original vortex method, in which the pitching moment amplitude grew over time for simulations involving multiple flapping cycles. The new approach described herein lumps far-field wake vortices to mimic the vortex decay, which is shown to improve the accuracy of the solution while keeping the pitching moment amplitude under control, especially for simulations involving many flapping cycles. Findings: In addition to improving the accuracy of the solution, the new method greatly reduces the computation time for simulations involving many flapping cycles. The solution of the original vortex method and the new method are compared to published Navier–Stokes solver data and show very good agreement. Originality/value: By utilizing a novel unsteady vortex method, which has been designed specifically to handle the highly unsteady flapping wing problems, it has been shown that the time to compute a solution is reduced by several orders of magnitude (Denda et al., 2016). Despite the success of the vortex method, especially for a small number of flapping cycles, the solution deteriorates as the number of flapping cycles increases due to the inherent lack of viscosity in the vortex method.

Original languageEnglish (US)
Pages (from-to)225-238
Number of pages14
JournalInternational Journal of Intelligent Unmanned Systems
Issue number3
StatePublished - Jun 26 2020

All Science Journal Classification (ASJC) codes

  • Modeling and Simulation
  • Automotive Engineering
  • Economics and Econometrics
  • Mechanical Engineering


  • Affordable CFD platform
  • Lumped wake vortex method
  • Unsteady flapping analysis
  • Vortex method


Dive into the research topics of 'The 2D lumped wake vortex method applied to unsteady flapping'. Together they form a unique fingerprint.

Cite this