Articles

Dimensionless Numbers

symscape — Tue, 29 Jul 2008 09:08:56 -0400

Dimensionless (or non-dimensional) numbers, such as the Reynolds number and Mach number, are a general concept (extensively used within fluid dynamics) to allow comparison between similar flow physics carried out at different scales and with different fluid properties.

OpenFOAM on Windows

symscape — Fri, 21 Mar 2008 13:57:35 -0400

OpenFOAM is a versatile open-source multi-physics simulation toolbox. It can simulate fluid flow (CFD), solid dynamics and electromagnetics (CEM). OpenFOAM was originally developed for Unix platforms, such as Linux, and until now there has not been a method for producing a native Windows version.

Geometry Exchange

symscape — Wed, 13 Feb 2008 13:31:16 -0500

If you are one of the lucky few that creates native geometry within a standalone Computer-Aided Engineering (CAE) analysis tool or within a single Computer-Aided Design (CAD) system with embedded CAE analysis tools, then stop reading now. Just a moment though, even if you have embedded CAE tools within your CAD system, but you import geometry for analysis you will still face geometry exchange challenges.

Solid Modeling

symscape — Wed, 14 Nov 2007 16:46:05 -0500

At the core of most Computer-Aided Design (CAD) software tools is a solid modeling system that uses a Boundary Representation (B-rep or BREP). The characteristics of complex objects, such as an airplane, can be assessed prior to manufacture because of their representation as a solid model. Most Computer-Aided Engineering (CAE) analysis tools have yet to embrace true solid modeling – for the pioneering few, such as SymLab, benefits abound.

Boundary Layers

symscape — Fri, 13 Jul 2007 14:47:13 -0400

Boundary layers are everywhere. We live within the Earth's planetary boundary layer. Airplanes exploit boundary layers to fly. Golf balls have dimples that alter boundary layer characteristics to maximize their flight time. So what are boundary layers?

Mach Number

symscape — Mon, 09 Apr 2007 10:58:05 -0400

The dimensionless Mach number is a means to represent the speed of an object through a fluid (or the speed of a fluid over an object) relative to the speed of sound in the fluid.

Reynolds Number

symscape — Thu, 05 Apr 2007 13:04:10 -0400

Dimensionless lift coefficient and drag coefficient values permit comparisons between similar shapes moving through a fluid. Such comparisons are only valid if the Reynolds numbers are also equivalent.

Pressure Coefficient

symscape — Thu, 05 Apr 2007 12:56:46 -0400

The pressure coefficient is a dimensionless quantity of interest to aerodynamicists.

Lift Force and Drag Force

symscape — Wed, 04 Apr 2007 17:23:52 -0400

Airplanes defy gravity. Formula 1 racing cars corner at incredible speeds generating lateral forces up to 4.5 times that of gravity. Yachts can circumnavigate the globe by wind power alone. These incredible feats are all due to the lift force generated by airfoils moving through air. Of course nothing comes for free; for lift, the cost is drag.

Meshing

symscape — Fri, 09 Mar 2007 09:05:08 -0500

Most Computer-Aided Engineering (CAE) analysis techniques, such as our Panel Flow add-on, require that the geometry be broken up into a mesh or grid to perform a calculation.