R&D on Wing-in-Ground, Transport-Amphibious Platforms, and Ships with Aerodynamic Support
Wing-In-Ground craft (WIG), or ekranoplans, are high-speed low-altitude vehicles that utilize a favorable ground effect to enhance their lift and lift-drag ratio (see picture above). The most advanced WIGs have been developed by the Central Hydrofoil Design Bureau (photos of several WIGs are available here). At the present time, several companies around the world are working on developing commercial Wing-in-Grounds.
I am collaborating with Nikolai Kornev on numrical modeling of Wing-In-Ground. I have been working with Nikolai's CFD code Autowing (see my other CFD work). An example of his important findings for small WIGs is shown below. In the take-off, when the craft detaches from the water surface, its speed increases, followed by the increase of the flight altitude. Small WIGs are usually unstable far from the surface, so this change in the altitude may result in heave-pitch instability, stall effect, and a crash (typical scenario of most accidents with WIGs). To avoid this, a pilot must reduce the thrust immediately after detachment from water up to the level corresponding to the crusing flight regime. Then, the WIG will smoothly proceed to the stable flight. You can find more detailed analysis of WIG motions and simulations in our paper,
I am currently working on Power Augmented Ram Vehicles (PARV), relatives of WIng-in-Ground. More information can be found on the web-site of my research group at WSU.
Aerodynamic unloading can benefit fast marine vehicle with speeds approaching 100 knots. Development of Ships with Aerodynamic Support (SAS) has a bright future since the speed becomes the most important factor for major sponsors of R&D research. I am working on a SAS comprising three planing hulls and an a wing-shaped platform. Three hulls are needed to provide high hydrodynamic efficiency (low length-beam ratio of a single hull) and to keep the vehicle dynamically stable. A catamaran with two short hulls will not be stable, and a catamaran with two long hulls will not be efficient in the planing regime. Tests demonstrated the highest lift-drag ratio of this concept at high speeds and exceptionally good seaworthiness (combination of the platform and three hulls appears to be very stable). Shown below are the tested model, possibleimplementation, and a comparison of experimental data for lift and drag aerodynamic coefficients with my calculations using vortex-lattice code Autowing and empirical friction drag. (triangle and dashed line correspond to the interceptor-augmented platform)
