Engineering contexts features

Cyclic Steady State (CSS) is a unique feature of periodic adsorption processes. It is defuied as a condition whereby the state at the end of each cycle is identical to that at its beginning. Within an engineering context, the theoretical determination of CSS for a given set of periodic conditirms is a key step towards the optimisation of adsorption processes. CSS determination computer simulation, however, is still one of the most challenging procedures for a process engineer to implement. Once achieved, the engineer is more readily able to maximise profit and minimise costs of the adsorption process. 

The evolution of a professional engineering context. In addition to the tasks that engineers perform, there is a broader set of aims and activities that form a professional context of engineering that is constantly evolving. It is interesting to note the features that are relatively stable in this environment, and those that are more rapidly evolving. The contextual elements that have not materially changed in the last 50 years include ... 

Maintain the passive nature (see Seetion 8.4.2 of this chapter for a discussion on what passive means in this context) of the engineered safety features. 

The functions of safety systems are initiated upon receipt of a signal from the protection system or manually. Some aspects of safety systems are often referred to as engineered safety features, particularly in the context of emergency heat removal and confinement. 

Koelman and Hoogerbrugge (1993) have developed a particle-based method that combines features from molecular dynamics (MD) and lattice-gas automata (LGA) to simulate the dynamics of hard sphere suspensions. A similar approach has been followed by Ge and Li (1996) who used a pseudo-particle approach to study the hydrodynamics of gas-solid two-phase flow. In both studies, instead of the Navier-Stokes equations, fictitious gas particles were used to represent and model the flow behavior of the interstial fluid while collisional particle-particle interactions were also accounted for. The power of these approaches is given by the fact that both particle-particle interactions (i.e., collisions) and hydrodynamic interactions in the particle assembly are taken into account. Moreover, these modeling approaches do not require the specification of closure laws for the interphase momentum transfer between the particles and the interstitial fluid. Although these types of models cannot yet be applied to macroscopic systems of interest to the chemical engineer they can provide detailed information which can subsequently be used in (continuum) models which are suited for simulation of macroscopic systems. In this context improved rheological models and boundary condition descriptions can be mentioned as examples. 

Several related problems have been previously considered in the literature. In addition to the afore mentioned statistical approaches for structural change detection in data sets and their application for linear system identification [7], the joint problem of model structure determination and parameter estimation was addressed by [8-10]. A related approach was used by [11-13] in the context of data reconciliation. Additional aspects of model selection in chemical engineering are covered in [14]. Although the present problem shares common features with the all of the previous applications, it also presents unique characteristics that require a specific formulation. 

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