By Chalmers University of Technology FROM CLASSICAL GAS DYNAMICS TO MODERN COMPUTATIONAL FLUID DYNAMICS The Compressible Flow website is a placeholder for information related to the Compressible Flow course available in the Applied Mechanics Master’s Program at the Chalmers University of Technology. The Compressible Flow website framework was set up Read more…
Aneurysm Clipping Clipping is a tried-and-true method of treating an aneurysm, a bulge in a weak area of an artery. Artery walls are under constant pressure from the high-pressure blood flow inside them. The constant pressure can cause a weak area of the wall to balloon out, forming an aneurysm. Read more…
Endovascular Coiling Endovascular coiling is a procedure performed to block blood flow into an aneurysm (a weakened area in the wall of an artery). Endovascular coiling is a more recent treatment for brain aneurysms; it has been used in patients since 1991. Endovascular coiling is a minimally invasive technique, which Read more…
Description of geometric indices Parent vessel geometric characterization Given the 3D surface model, vessel centerlines are computed for all the available segments and are available for download on the website. Only the tract hosting the aneurysm is used for the geometric characterization. The segment under investigation is extracted from the Read more…
What is a cerebral aneurysm? A cerebral aneurysm is a bulge in a weak area of the wall of a brain artery. It puffs out like a small balloon and fills with blood. It is also called an intracranial aneurysm or brain aneurysm. This bulge makes the artery more likely Read more…
Mesh Generation Mesh or grid is defined as a discrete cell or elements into which the domain/ model is divided. All the flow variables & any other variables are solved at centres of these discrete cells. This entire process of breaking up a physical domain into smaller sub-domains (elements/ cells) Read more…
What is Cavitation? Cavitation happens when vapor bubbles form in a liquid because flow dynamics cause the local static pressure to drop below the vapor pressure. Without accurate prediction of cavitation, users cannot effectively optimize designs and set operating parameters and limits, potentially exposing their products to unexpected vibration and Read more…
3D Blood Flow Simulation Bio-medical researchers have been relying on computational fluid dynamics to model and understand the physical mechanisms behind the formation and progression of hemodynamic disorders. Wall shear stress (WSS) exerted on the walls of the blood vessel due to the flow of blood is one of the Read more…
Pressure The pressure could be measured by different devices such as barometer, piezometer and Pitot tube. A barometer is a scientific instrument that is used to measure air pressure (atmospheric pressure) in a certain environment. Pressure tendency can forecast short term changes in the weather. The atmospheric pressure (ambient pressure) causes the fluid Read more…
During floods, the density of river water usually increases due to a subsequent increase in the concentration of the suspended sediment that the river carries, causing the river to plunge underneath the free surface of a receiving water basin and form a turbidity current that continues to flow along the bottom.
The study and understanding of such complex phenomena is of great importance, as they constitute one of the major mechanisms for suspended sediment transport from rivers into oceans, lakes or reservoirs. Unlike most of the previous numerical investigations on turbidity currents, in this project, a 3D numerical model that simulates the dynamics and flow structure of turbidity currents, through a multiphase flow approach is proposed, using the commercial CFD code FLUENT.
A series of numerical simulations that reproduce particular published laboratory flows are presented. The detailed qualitative and quantitative comparison of numerical with laboratory results indicates that apart from the global flow structure, the proposed numerical approach efficiently predicts various important aspects of turbidity current flows, such as the effect of suspended sediment mixture composition in the temporal and spatial evolution of the simulated currents, the interaction of turbidity currents with loose sediment bottom layers and the formation of internal hydraulic jumps.
Furthermore, various extreme cases among the numerical runs considered are further analyzed, in order to identify the importance of various controlling flow parameters.
3D Laboratory Setup
Geometry, mesh and boundary conditions used in the numerical simulations
X Velocity Contours of Turbid Currents
This numerical project was conducted by XAV experts.