in this study, a pellet scale model was developed for trickle bed reactor utilizing cfd techniques. drag coefficients were calculated numerically at different velocities and bulk porosities in the case of single phase flow through the dry bed. the simulation results were then compared with the prediction of kozeny-carman (k-c) equation. the results indicated that drag coefficients calculated fr...

air pollution is one of the major issues about the diesel engines in todays' world. it is a special concern in those areas that have difficulty meeting health-based outdoor air quality standards. natural gas has low emission and resource abundance and also conventional compression ignition engine can be easily converted to a dual fuel mode to use natural gas as main fuel and diesel as pilo...

Three different cyclist positions were evaluated with Computational Fluid Dynamics (CFD) and wind-tunnel experiments were used to provide reliable data to evaluate the accuracy of the CFD simulations. Specific features of this study are: (1) both steady Reynolds-averaged Navier-Stokes (RANS) and unsteady flow modelling, with more advanced turbulence modelling techniques (Large-Eddy Simulation -...

This paper presents a short review of the applications of CFD to indoor environment design and studies, and briefly introduces the most popular CFD models used. The paper concludes that, although CFD is a powerful tool for indoor environment design and studies, a standard procedure must be followed so that the CFD program and user can be validated and the CFD results can be trusted. The procedu...

OBJECTIVE To evaluate whether virtual surgery performed on 3-dimensional (3D) nasal airway models can predict postsurgical, biophysical parameters obtained by computational fluid dynamics (CFD). METHODS Presurgery and postsurgery computed tomographic scans of a patient undergoing septoplasty and right inferior turbinate reduction (ITR) were used to generate 3D models of the nasal airway. Prio...

Considerable progress in development and application of computational fluid dynamics (CFD) for aeroengine internal flow systems has been made in recent years. CFD is regularly used in industry for assessment of air systems, and the performance of CFD for basic axisymmetric rotor/rotor and stator/rotor disc cavities with radial throughflow is largely understood and documented. Incorporation of t...

Objective The objective was to study the performance of an in-house developed wall shear stress (WSS) algorithm using PC-MRI in intracranial aneurysms. Materials & Methods First, the algorithm was applied to a high resolution in vitro PC-MRI measurement under steady and pulsatile fl ow conditions. A CFD simulation was performed with similar infl ow boundary conditions. Second, WSS was estimated...

This paper discusses a framework for integrated Augmented Reality (AR) architecture for indoor thermal performance data visualization that utilizes a mobile robot to generate environment maps. It consists of three modules: robot mapping, Computational Fluid Dynamics (CFD) simulation, and AR visualization. The robot mapping module enables the modelling of spatial geometry using a mobile robot. I...

The relationship between the morphology and blood flow of the Left Ventricle (LV) during myocardial remodelling is complex and not yet fully understood. Cardiovascular MR (CMR) velocity imaging is a versatile tool for the observation of general flow patterns in-vivo. More detailed understanding of the coupled relationship between blood flow patterns and myocardial wall motion can be further enh...

A three dimensional (3D) computational fluid dynamics (CFD) simulation and a neural network model are presented to estimate the behaviors of the Colburn factor (j) and the Fanning friction factor (f) for wavy fin-and-flat tube (WFFT) heat exchangers. Effects of the five geometrical factors of fin pitch, fin height, fin length, fin thickness, and wavy amplitude are investigated over a wide range...