Space-time correlations of passive scalar in Kraichnan model

Autor: Ping-Fan Yang, Liubin Pan, Guowei He

Publikováno v: Theoretical and Applied Mechanics Letters, Vol 13, Iss 5, Pp 100470- (2023)

We consider the two-point, two-time (space-time) correlation of passive scalar R(r,τ) in the Kraichnan model under the assumption of homogeneity and isotropy. Using the fine-gird PDF method, we find that R(r,τ) satisfies a diffusion equation with c

Externí odkaz: https://doaj.org/article/daf313ec54754668b38248858aba9cbb

Homogeneity constraints on the mixed moments of velocity gradient and pressure Hessian in incompressible turbulence

Autor: Ping-Fan Yang

Publikováno v: Physical Review Fluids. 8

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::ed5cbce034023ac8c593ca885207a704
https://doi.org/10.1103/physrevfluids.8.024601

Spin selector based on periodic diluted-magnetic-semiconductor/nonmagnetic-barrier superlattices

Autor: Ping-Fan Yang, Rui Zhu, Yong Guo

Publikováno v: AIP Advances, Vol 5, Iss 7, Pp 077115-077115-7 (2015)

We propose a spin selector based on periodic diluted-magnetic-semiconductor/nonmagnetic-barrier (DMS/NB) superlattices subjected to an external magnetic field. We find that the periodic DMS/NB superlattices can achieve 100% spin filtering over a dram

Externí odkaz: https://doaj.org/article/e614be287b9543ccbd12a2249728d8ac

Dynamics and invariants of the perceived velocity gradient tensor in homogeneous and isotropic turbulence

Autor: Alain Pumir, Haitao Xu, Ping-Fan Yang

Publikováno v: Journal of Fluid Mechanics
Journal of Fluid Mechanics, 2020, 897, ⟨10.1017/jfm.2020.375⟩
Journal of Fluid Mechanics, Cambridge University Press (CUP), 2020, 897, ⟨10.1017/jfm.2020.375⟩

The perceived velocity gradient tensor (PVGT), constructed from four fluid tracers forming a tetrahedron, provides a natural way to study the structure of velocity fluctuations and its dependence on spatial scales. It generalizes and shares qualitati

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::32f49281e3daff0af9455176b1b619dc
https://hdl.handle.net/21.11116/0000-0006-ACBB-6

Spin-dependent tunneling time in periodic diluted-magnetic-semiconductor/nonmagnetic-barrier superlattices

Autor: Ping-Fan Yang, Yong Guo

Publikováno v: Applied Physics Letters. 108:052402

We investigate the tunneling time (dwell time) in periodic diluted-magnetic-semiconductor/nonmagnetic-barrier (DMS/NB) superlattices subjected to an external magnetic field. It is found that spin-dependent resonant bands form in the spectra of dwell

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::6ad5ce2ed5b3d785707261a4f957dfca
https://doi.org/10.1063/1.4941302