Mesoscale problems

Most chemical engineering processes involve complex multiphase fluid systems, and their evolution depends on the mechanism by which the inhomogeneous subsystems exchange information at different length scales. Whereas numerous theoretical methods with specific description accuracies have been developed for investigating physicochemical properties of various fluid systems, a unified theory that enables the investigation of mesoscale problems is still needed. Here, we introduce a unified... 

We will discuss multiscale issues in the FTS process by analyzing these three scales particularly and find how the mesoscale problem affects FTS reaction on the product distribution by coupling multiscale issues. 

Based on mentioned above, the slurry bubble reactor is very complex, such as the size of catalyst and bubble, the behavior of catalyst and bubble, as well as the contact of catalyst and bubble in the reactor, indicating that the mesoscale problem is also very important for designing the slurry bubble reactor. 

As summaries, the influence of product distribution for FTS was discussed from two aspects of multiscales and mesoscale. It can be found that the multiscale problem widely appears on FTS, and one of the most prominent is the ASF distribution, which is derived based on the polymerization mechanism. Flowever, as the research of mesoscale problems of FTS is just on a primary level, there are only several examples to describe mesoscale phenomena of FTS, as mentioned above, such as molecular reaction—diffusion. 

Gradually, people recognized that meso will be a big thing. Most importandy, there are many clues that a common principle for all mesoscale problems at different levels between elemental particles and the universe may exist, leading to exploration of a transdisciphnary science, mesoscience, though great efforts are needed to further clarify its rationale and importance. 

Although these contributions may be preliminary in addressing mesoscale problems, we hope these two volumes can play a role of throwing out a minnow to catch a whale and to stimulate thinking in the following questions what are mesoscale phenomena Why are they so important How to relate mesoscale concepts to our research Is it necessary or possible to have a common science for aU mesoscales ... 

Eremeev VN, Ivanov VA, Kosarev AN, Tuzhilkin VS (1992) Climatic thermohaline fields of the Black Sea waters with mesoscale resolution three-dimensional structure and annual variability. In Problems of the Black Sea (international conference). Sebastopol, Ukraine, 10-15 November 1992. MHI UAS, Sebastopol, p 209... 

It is natural that this book could not reflect all the problems of the Black Sea. Meanwhile, its content makes clear the objectives of the future research. In the temporal range, they extend from the mean condition of the oceanographic fields, which are studied best of all, toward both to mesoscale processes and to the interannual variability of the condition of the marine ecosystem. Among the wide spectrum of urgent problems of the Black Sea we should emphasize the following. 

Antonietti M, Ozin GA (2004) Promises and problems of mesoscale materials chemistry or why meso Chem Eur J 10 29-41... 

Mesoscale self-assembly We have not yet modeled MESA by computer, but with the wealth of experimental results we are in a position to develop believable computer simulations calibrated by experiment. The force of attraction between the objects is well understood mathematically in a number of cases [33,120] and in some systems it may be possible to measure these forces experimentally [149]. Some of the problems encountered in modeling molecular systems will also be encountered in modeling MESA. For example, finding global rather than local minima, the availability of computer time limiting how long the assembly can be modeled, and constructing potential functions for interactions that have not been determined... 

The use of local theories, incorporating parameters such as the eddy viscosity Km and eddy thermal conductivity Ke, has given reasonable descriptions of numerous important flow phenomena, notably large scale atmospheric circulations with small variations in topography and slowly varying surface temperatures. The main reason for this success is that the system dynamics are dominated primarily by inertial effects. In these circumstances it is not necessary that the model precisely describe the role of turbulent momentum and heat transport. By comparison, problems concerned with urban meso-meteorology will be much more sensitive to the assumed mode of the turbulent transport mechanism. The main features of interest for mesoscale calculations involve abrupt... 

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