Ground Effect Vehicles
The airflow around the wing of an aircraft flying in close proximity to the ground differs greatly in comparison to the airflow around a wing of an aircraft flying at altitude. The presence of the ground creates a significant aerodynamic affect that can increase lift without a drag penalty, consequently improving the aerodynamic efficiency.
This phenomenon is known as in-ground effect and is the basis for craft known as WIG (Wing-In-Ground-effect), GEV (Ground Effect Vehicles) or by the Russian term Ekranoplan. These craft are fascinating, neither conventional aircraft nor surface vessel. They fly within metres of the surface, typically water, at speeds far exceeding those of a normal surface vessel. There are of course limitations to GEVs.
This web page primarily is concerned with the aerodynamics of GEVs through a combination of literature reviews and my personal research using CFD (computational fluid dynamics).
- DHMTU Aerofoil DefinitionWithout doubt, the nation that has progressed ground-effect-vehicles the furthest is Russia. More specifically, this was the USSR from the 1960s through to the late 1980s with their Ekranoplan aircraft. These GEVs (Ground Effect Vehicles) were designed by the Central Hydrofoil Design Bureau, at the heart of the aerodynamic design was the Department of Hydromechanics […]
- Introducing GEVfoilI have decided to rename my little aerofoil project. I found no fewer than four other projects using the previous name, which I’ll avoid stating to reduce confusing search engines any further. I’ve settled on GEVfoil (Ground Effect Vehicle Aerofoil) which may seem a little obvious, but clarity should at least be in my favour. […]
- Ramer–Douglas–Peucker algorithmGenerally speaking, for low-speed flow around an aerofoil, the largest gradients in the flow-properties coincide with the greatest curvature of the aerofoil, and thus are the region that requires the greatest concentration of cells (or nodes) in the computational domain. Many of the simplified treatments for spacing points along an aerofoil use a logarithmic spacing […]
- GEVfoil – NACA 4 Series Part 2 and CSV ReadingPreviously I had made a simple function that will generate a number of points/coordinates for any specified NACA 4 series aerofoil. The limitation with this approach was that it did a fairly poor job at capturing the leading-edge. The leading edge is of critical importance to the aerodynamic performance and characteristics of the aerofoil. After […]
- GEVfoil – NACA 4 SeriesThe intention behind GEVfoil is to establish an open-source set of Python classes to handle aerofoils (American English: airfoils). The intention is that these can be used for anything from generating simple point clouds, analytical representations all the way to STL files for CFD meshing and OpenFOAM BlockMesh output. The first step is starting with something basic, […]