Education.

  • 2020--2021

    Postdoctoral researcher, Mechanical Engineering department, Johns Hopkins University, Baltimore, Maryland

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  • 2014--2020

    Ph. D. candidate, Mechanical Engineering department, Johns Hopkins University, Baltimore, Maryland

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  • 2014-2016

    Master's degree, Mechanical Engineering department, Johns Hopkins University, Baltimore, Maryland

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  • 2010-2014

    Bachelor of Science, Department of theoretical and applied mechanics, Peking University, Beijing, China

Research.

Olfactory search algorithms in turbulent environments

Searching the pollution source in turbulent environments from remote sensing is challenging due to turbulent dispersion and molecular diffusion. We developed and implemented a forward-adjoint looping algorithm to optimize the source spatial profile.

The difficulty of reconstruction lies in the highly-correlated sensor measurements when the source is shifted. The effect of turbulent dispersion and molecular diffusion onto the quality of the reconstruction is investigated and reported.

Optimal sensor placement for passive scalar source search in turbulent environments

Optimal sensor placement is selected by minimizing the condition number of the impulse-response system. We further developed a subspace-tracking algorithm to iteratively update the sensor locations.

Data assimilation and state estimation in turbulent flows

We reconstructed the initial flow state by minimizing the squared error of later wall measurements. The Hessian of the cost function were constructed. Its eigenvectors were analyzed to interpret the fundamental difficulty.

Wake-induced cross-flow instability on a swept airfoil

Laminar-turbulence transition of a swept airfoil due to turbulent wake from the leading-edge slat was modeled and analyzed. Different transition mechanisms were analyzed and compared with Linear Stability Theory (LST).

Data assimilation in compressible flows

Sensitivity of wall pressure measurement on a compressible boundary layer to the free-stream condition.

Data assimilation in stratified flows

Flow state estimation from sparse measurements in stratified flow scenarios, especially with the presence of internal gravity waves.

Layer 1

Publications.

Spatial reconstruction of steady scalar sources from remote measurements in turbulent flow, Journal of Fluid Mechanics, 2019

Derived and implemented the discrete adjoint for three dimensional advection-diffusion equation.

Performed source localization using forward-adjoint loops and tested different source-sensor arrangements.

Quantified the effect of turbulent dispersion and molecular diffusion in source reconstruction.

Read the article

Kriging-enhanced ensemble variational data assimilation for scalar-source identification in turbulent environments, Journal of Computational Physics, 2019

Developed code to construct source-response system from ensemble of trial sources.

Determined the optimal sensor placement using condition number minimization framework.

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Discrete adjoint of fractional-step incompressible Navier-Stokes solver in curbilinear coordinates and application to data assimilation, Journal of Computational Physics, 2019

Developed massively parallel discrete adjoint code for Navier-Stokes solver in generalized curvillinear coordinates.

Derived and implemented conjugate-gradient based orthogonal projector to project adjoint fields onto solenoidal space while satisfying the Lagrangian identity to machine precision.

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Seminars & Teaching.

Layer 1

Amateur Pianist Experience

     music resume

Chopin Concerto No.1, Movement 1

Peabody Piano Week 2019, accompaniment: Kaili Ho

Bach, English Suite No. 2

Peabody Piano minor graduation recital

Seattle International Piano Competition

Contact.

qiwang065@gmail.com skype: qi.wang68 1(305)394-1722
  • Room 323,
  • Latrobe Hall,
  • Mechanical Engineering Department,
  • Johns Hopkins University