联系我们
意见反馈

关注公众号

获得最新科研资讯

分享到
实验室简介

     

Welcome to the research page of Prof. Shuiqing Li at Tsinghua University. The overarching theme of my research is the physical understanding of particle media at various length scales, such as macro-scale (granular)micro-scale (dust) and atomic-scale (nanoparticle), in combination with multi-field effects encompassing viscous flowsthermal boundary layerselectrostaticslaser optics, and chemically heterogeneous reactions.

Together with my graduates and collaborators, first we are working towards the development of modern particle-level approaches for analyzing and simulating particulate flows at mesoscale, in particular, focusing on problems with small adhesive particles. Second, we are also curiously exploring the underlying mechanism of multiscale problems with heterogeneous chemically reactive flow over particle surfaces or near walls, spanning from reactive materials, flame-made aerosols, in situ nano-catalysts, etc. Benefiting from above fundamentals, we are not only developing the clean coal and oxy-coal combustion technologies, but also interest in any advanced methods related to dust mitigation, particle coagulation, and particulate removal.

Generally, we have activities built around multiphase flows, heterogeneous reactive flow, physical chemistry, and physicochemical hydrodynamics relevant to energy conversion (primarily combustion) and environmental engineering. We enjoy new challenges and collaborations. Feel free to visit us, either in person or on the web.

http://www.thu-lishuiqing.org

还没有发布内容

Adhesive Particulate Media

The packings of non-adhesive granular matter have been extensively studied, with two well-known packing limits identified as the Random Close Packing (RCP) and the Random Loose Packing (RLP). However, for micron-sized particles, the presence of adhesive interactions such as van der Waals forces could intrinsically change the packing properties, which have not been well understood. In this work, we systematically generate a large set of micro-particle packings with arbitrary adhesion and friction by means of adhesive DEM simulation. A dimensionless adhesion parameter and the friction coefficient  are found to well characterize the bulk properties of the adhesive packings. A universal equation of state  as well as a new phase diagram is derived to describe the ensemble of the generated packings, which immensely expands the classical phase diagram of the jammed granular matter (Song C, Wang P, Makse HA, Nature, 2008, 453(7195): 629-632).

 

Publications:

Liu WW, Li SQ*, Baule A, Makse HA*.  Adhesive loose packings of small dry particles. Soft Matter,  11(32), 6492-6498 (2015).

Liu WW, Jin Y, Chen S, Makse HA, Li SQ*. Equation of state for random sphere packings with arbitrary adhesion and friction. Soft Matter, 13, 421-427 (2017).

Plasma

The plasma-assisted ignition enhancement of pulverized lignite particles is intensively studied in a laminar, upward Hencken flat-flame burner. Under the conditions of different oxygen mole fractions, the discharge mechanisms and the reductions of ignition delay time are examined to distinguish the chemical and thermal effects on the ignition enhancement. This work provides a preliminary understanding of plasma-assisted ignition mechanisms on dispersed coal particles that may be applied in the practical combustion system.

 

Publication:Zhao FX, Li SQ, Ren YH, Yao Q, Yuan Y. Investigation of mechanisms in plasma-assisted ignition of dispersed coal particle streams. Fuel,  186: 518-524 (2016).

Clean Coal Combustion

This figure illustrates our fundamental researches on coal combustion, as a function of coal particle residence time in high-temperature ambiances. Combined with advanced in-situ diagnostics as well as standard off-line measurements, aspects like particle ignition, surface temperature, fragmentation properties, minerals release, particulates formation, and ash deposition were intensively investigated. Predictions were also made by developed models after revealing the dominant mechanisms in these processes.

访问量:422