Recent years have witnessed significant improvements in the computer modeling of fluidized particle systems. Such models hold the potential to simulate complex systems and thus greatly reduce design efforts. As we approach the goal of simulating arbitrary systems, there exists a greater need to challenge the ability of the models to predict key features of operating beds. The simplest challenge...

The Restricted Shortest Path (RSP) problem, also known as the Delay-Constrained Least-Cost (DCLC) problem, is an NP-hard bicriteria optimization problem on graphs with n vertices and m edges. In a graph where each edge is assigned a cost and a delay, the goal is to find a min-cost path which does not exceed a delay bound. In this paper, we present improved approximation schemes for RSP on sever...

1. The statement of the problem. Let B denote the boundary of a smooth, closed and bounded surface in £ , and V the exterior of B. Erect a spherical polar coordinate system with origin interior to B; and denote by r a point (r, 0, ) in V and by TB a point (r#, 6B, 4>B) on B. Further let v be a scalar wave function for the exterior V, i.e., (a) v(r) is of class C, r £ 7 = VVJB, (b) ( V 2 +^ 2...

In this work, we develop a self-consistent physical model of bubbles in a gas solid two-phase 1 flow. Using the Peng-Robonson state equation and a detailed specific heat ratio equation of bubbles, 2 we obtain the kinetic equations of the bubbles on the basis of the Ergun equation, thermodynamic 3 equations, and kinetic equations. It is found that the specific heat ratio of bubbles in such syste...

The fluidization and reduction behavior of micron-sized iron oxide powder, produced by combustion, is studied in a lab-scale cylindrical fluidized bed. minimum velocity umf found to stabilize above normalized static bed heights 0.5 H/D (static height divided the diameter). measured as function temperature between 280 860 K for both H2 N2 fluidizing gas. experimental results start deviate from E...

Meso-scale structure existing in the form of particle clusters or strands in concurrent-up gas–solid two-phase flow has been extensively corroborated in experimental research. However, its significant effects on interfacial drag coefficient are seldom taken into account in current computational fluid dynamic (CFD) simulations by using the two-fluid models. The energy-minimization multi-scale (E...

Two mathematical models for tumour anti-angiogenesis, one originally formulated by Hahnfeldt et al. (1999, Tumor development under angiogenic signaling: a dynamical theory of tumor growth, treatment response, and postvascular dormancy. Cancer Res., 59, 4770-4775) and a modification of this model by Ergun et al. (2003, Optimal scheduling of radiotherapy and angiogenic inhibitors. Bull. Math. Bio...