55 research outputs found
Transient behavior of the thermocapillary migration of drops under the influence of deformation
The transient thermocapillary migration of drops with nontrivial deformation
is studied. The finite difference method is employed to solve the
incompressible Navier-Stokes equations coupled with the energy equation; the
front-tracking method is adopted to track the moving deformable drop interface.
In the hot region, deformations of drops increase with the decrease of
interfacial tensions. In order to indicate the temperature impact on the
interfacial tension, a local capillary number () is introduced. It is
found that, when the drop density is smaller/larger than that of the bulk
fluid, the drop velocity decreases/increases with the increase of the drop
deformation.Comment: 18 pages, 14 figures. The Chinese version of this paper has been
accepted by "Scientia Sinica: Physica, Mechanica & Astronomica
Non-Markovian epidemic spreading on temporal networks
Many empirical studies have revealed that the occurrences of contacts
associated with human activities are non-Markovian temporal processes with a
heavy tailed inter-event time distribution. Besides, there has been increasing
empirical evidence that the infection and recovery rates are time-dependent.
However, we lack a comprehensive framework to analyze and understand
non-Markovian contact and spreading processes on temporal networks. In this
paper, we propose a general formalism to study non-Markovian dynamics on
non-Markovian temporal networks. We find that, under certain conditions,
non-Markovian dynamics on temporal networks are equivalent to Markovian
dynamics on static networks. Interestingly, this result is independent of the
underlying network topology
Implementation of a flexible and modular multiphase framework for the analysis of surface-tension-driven flows based on a LS-VOF approach
The mathematical modelling and numerical simulation of multi-phase flows are both a demanding and highly complex exercise. In typical problems with industrial relevance, the fluids are often in non-isothermal conditions and interfacial phenomena are a relevant part of the problem. A number of effects due to the presence of temperature differences must be adequately taken into account to make the results of numerical simulations consistent and realistic. Moreover, in general, gradients of surface tension at the interface separating two liquids are a source of numerical issues that can delay (and even prevent completely in some circumstances) the convergence of the solution algorithm. Here, we propose a fundamental and concerted approach for the simulation of the typical dynamics resulting from the presence of a dispersed phase in an external matrix in nonisothermal conditions based on the modular computer-aided design, modelling, and simulations capabilities of the OpenFOAM environment. The resulting framework is tested against the migration of a droplet induced by thermocapillary effects in the absence of gravity. The simulations are fully three-dimensional and based on an adaptive mesh refinement (AMR) strategy. We describe in detail the countermeasures taken to circumvent the problematic issues associated with the simulation of this kind of flows
Cardiac autonomic function in patients with acute exacerbation of chronic obstructive pulmonary disease with and without ventricular tachycardia
On statistical-mechanical descriptions of decaying two-dimensional turbulence
+110hlm.;24c
Analysis on Mortgage of Farmland Contractual Management Right and Countermeasures
In recent years, a series of pilot projects in mortgage of farmland contractual management right have been carried out in some regions. However, there is considerable dispute over whether the farmland contractual management right can be mortgaged in the practice of China’s legislation on land circulation. We firstly introduced current situations of mortgage of farmland contractual management right in China. Then, we analyzed existing problems in mortgage of farmland contractual management right. Finally, we put forward corresponding countermeasures and recommendations, to bring into full play land use efficiency, more rationally distribute land resource, and further promote development of rural economy
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