Modelling down-scaling

Both, off-line and on-line coupling of MetMs and ACTMs are useful in different applications. Thus, a timely and innovative field of activity will be to assess their interfaces, and to establish a basis for their harmonization and benchmarking. It will consider methods for the aggregation of episodic results, model down-scaling as well as nesting. The activity will also address the requirements of meso-scale meteorological models suitable as input to air pollution models. 

For the research or assessment mode, the models can be more sophisticated, including the large eddy simulations (LES) or other high-order turbulence closure models, down-scaling with obstacle-resolved computer fluid dynamics (CFD) tools, but such models are very expensive computationally (see e.g., Mahura et al., 2005 [389]). For the forecasting mode, the models have to be fast enough therefore, they use... 

An example of the application of a unified model to the design of a three-phase, fluidized bed bioreactor is the scale down, scale up procedure. A model of the full scale reactor is developed, then is used to design... 

As mentioned earlier, in principle, one can model the dynamics of a simple classical fluid by means of MD simulations. This technique, although straightforward, is relatively time-consuming, and therefore not suitable for observation of large-scale macroscopic phenomena in the fluid. However, one often does not need such a detailed description of the microdynamics as provided by MD. In such cases, it would be more efficient to strip the MD model down to its barest essentials, where the only requirement is that the model behaves like a fluid macroscopically, but is still atomistic in character—i.e., the mechanism underlying the fluid motion is the movement of particles. From the derivation of... 

As for the physics of the fully ionized hot plasma core, appropriate dimensionless parameters have been identified present fusion research acts like wind-channel experiments on down-scaled models, with respect to future fusion power reactors. 

If Small scale experiments are to be used for evaluation purposes, then they must be designed to have blend time, pumping capacity and shear rate levels relatively similar to full scale installation. This normally means a non-geometric model of scale-down to control various mixing parameters. 

Fig. 16.1 (a) Deterministic modelling systems developed at DMI and (b) model nesting in Urban Air Quality Information and Forecasting Systems (UAQIFS) (... common regulatory models FUMAPEX multi-scale systems new suggested down-scaling with obstacle-resolved models)... 

The model system generally uses EMEP emissions. For the countries - Austria, Czech Republic, Slovakia and Hungary - the original 50 x 50 km data are down-scaled to 5 X 5 km based on an inventory from 1995 (Winiwarter and Zueger 1996). The EMEP data for 1999 (used for 2005 forecast) have been substituted by data for 2003 (Vestreng et al. 2004). In addition, a new highly resolved emission inventory for the city of Vienna, Austria (Orthofer et al. 2005) is used for this area. 

Several predictive methods have been applied to the tablet compaction process on a small scale to envisage what will happen on a large scale. Dimensional analysis has been described by Levin as a method of developing functional relationships that describe any given process in a dimensionless form to facilitate modeling and scale-up (or scale down). Although, theoretically, dimensional analysis can be applied to tablet manufacture, no examples are found in the literature. 

The purification processes used to obtain therapeutic plasma proteins at industrial scale are old and established. Often, they also lack the complete package of necessary process development and validation data when held against today s standards. These data voids can be successfully backfilled by dividing a complex purification process into manageable process modules constructing qualified down-scale models of these modules performing designed experiments... 

The development of a qualified down-scale model of a process module is integral to the approach of process validation using bench-scale experiments, as described earlier. We have developed down-scale models of process steps ranging from various types of process chromatography for protein purification to separation by precipitation and filtration. These down-scale models have been utilized to evaluate the effects of relevant process parameters on product-quality attributes. The normal logical sequence of process development, of course, is bench scale to pilot scale to full scale. However, for many plasma protein purification processes, a reverse order needs to be followed. As licensed full-scale processes already exist, the full-scale process steps need to be scaled down to construct small process models in order to evaluate the robustness of process parameters on the product without impacting full-scale production. These models can also be utilized to evaluate process changes, improvements, and optimizations easily and economically. 

Once enough process knowledge has been acquired, the next step involves the development and qualification of an appropriate down-scale model where the parameters of interest can be effectively studied. We normally qualify our down-scale models by processing a small portion of the input... 

The affinity chromatography process can be considered robust within the process parameter ranges studied using a qualified down-scale model. 

The down-scale process models provide an easy way to evaluate the effect of process parameters on the quality attributes of a product. These models are especially useful in a situation where a validation databank must be backfilled for existing full-scale manufacturing processes that were not validated during implementation according to the standards of today. 

Continue to generate high-resolution climate models that project probable future climate change at the regional scale and can be down-scaled to project future climate for individual catchments. 

Disadvantages Natural solid sump in bottom, Boilout cycles are usually frequent. Internal down-pipe may plug. Difficult to model and scale-up. Flow patterns in suspension chamber not uniform. 

In Germany, the Battelle Institute has employed the Battelle model containment (BMC) which is a 1/100 down-scaled model of a typical PWR containment. Between... 

Table VI shows that the data sets do produce slightly different structures. The SRRC program was used with the RMF and MGW data sets and the Sarko-Muggll (22) monomeric coordinates to determine the best values of chain rotation, translation and 06 rotation (06 was restricted to the tg range of positions) for up, down and antiparallel models. The scale factors ranged between 0.7 and 1.0.

Simoglou A, Argyropoulos P, Martin EB, Scott K, Morris AJ, Taama WM (2001) Dynamic modeling of the voltage response of direct methanol fuel cells and stacks. Part II feasibility study of model-based scale-up and scale down. Oiem Eng Sci 56 6761-6772... 

The simplest way to conduct the simulations of mesoscopic phenomena, consists in down-scaling of the continuum approach or upscaling (or coarse graining) the particle model. The limitation of the first approach is determined by the granular properties of matter, which are revealed for very small system. The behavior of granular fluid is different from that in the bulk. For example, very small systems may exhibit solid-liquid coexistence over a range of temperature different than that for large systems [31]. However, new approaches such as ... 

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