Saab Automobile AB

About: Saab Automobile AB is a based out in . It is known for research contribution in the topics: Radar & Signal. The organization has 760 authors who have published 890 publications receiving 11811 citations.

Processing of tank signal in radar level gauge system

Abstract: A method and a system for processing a reflected microwave signal generated by a radar level gauge system arranged to transmit microwaves towards the material in the tank, and receive a reflection of said microwave signal as a tank signal. The tank signal is processes by a plurality of processes, each process being adapted to determine a process variable in a specific region of the tank, each specific region corresponding to a predefined propagation distance range. Such multi-processing of the received tank signal has the advantage that each process can be optimized to that particular region of the tank. More specifically, a process concerned with a particular region of tank only needs to treat a portion of the tank signal.

Light ballistic protection as building elements

Abstract: The present invention concerns a ballistic protection against objects such as projectiles from fire arms, alternatively scatter from for example hand grenades. The protection comprises an enclosure (1, 2, 4, 5, 6, 7, 9) adapted so that the object (10) can penetrate the enclosure (1, 2, 4, 5, 6, 7, 9) in at least one area (2); at least one intermediate layer (3) comprising granules (27) arranged within the enclosure (1, 2, 4, 5, 6, 7, 9), which intermediate layer (3) and enclosure (1, 2, 4, 5, 6, 7, 9) are arranged to deaccelerate said object (10). The invention is further characterized in that: the granules (27) are movable arranged with respect to each other; the space in the intermediate layer (3) that is not occupied by granules (27) is filled by a gas medium to enable contact between adjacent granules (27); the granules (27) have mechanical properties so that a granule (27) is crushed and spread in the intermediate layer (3) when it is hit by an object (10), at the same time as adjacent granules (27) are subjected to impulses with a subsequent energy dissipation so that the object and fragments thereof remains in the protection with a reduced risk for ricochets.

Numerical and Experimental Investigations on Highly Integrated Subsonic Air Intakes

Abstract: Aerodynamic integration of air intakes and the optimization of their performance are challenging tasks for innovative design of advanced unmanned aerial vehicles (UAVs). The extension of Computational Fluid Dynamics (CFD) into application areas such as dynamic intake distortion prediction and thus engine/intake compatibility is made possible by modern hybrid methods and increasing computer resources. Within the Aerodynamics Action Group AD/AG-46 “Highly Integrated Subsonic Air Intakes” of the Group for Aeronautical Research and Technology in EURope (GARTEUR), CFD computations were carried out for the EIKON UAV configuration, which was designed and wind tunnel tested at FOI in Sweden. The major objectives of AD/AG-46 were to investigate the capability of Detached Eddy Simulation (DES) methods for the analysis of unsteady flow phenomena of serpentine air intakes and the accuracy levels of the computations. Numerical results for a variety of wind tunnel conditions were compared with Reynolds-Averaged Navier-Stokes (RANS) and unsteady RANS (URANS) data as well as with experimental results. The impact of not considering the wind tunnel walls in the CFD calculations on the computational results was investigated, revealing that the ventilated walls of the T1500 wind tunnel eliminate the blockage of the model within the closed test section and that free stream conditions can be applied for the computational boundary conditions. Since intake lip shaping is a vital design parameter impacting the intake internal flow and performance, the original geometry was compared with a modified cowl while maintaining low-observability features of the W-shaped cowl design. A trade-off study between boundary layer diversion versus ingestion was performed numerically by applying Euler boundary conditions to the walls of the numerical model of the UAV configuration, thus simulating the total removal or diversion of the boundary layer. The computed inviscid results were compared with the viscous data, quantifying the losses in total pressure recovery and the increase in distortion for the ingested test cases. Internal flow control in the intake duct of the UAV configuration was studied by numerically applying vortex generators, and the results were compared with experimental data. Numerical models were employed in order to simulate micro-jets as active flow control devices in the serpentine duct. Increasing of jet velocities resulted in smaller areas of flow separation and thus led to beneficial total pressure recoveries and distortion parameters. At DLR in Gottingen experiments with a generic high aspect ratio diverterless intake model were performed in the cryogenic blowdown wind tunnel DNW-KRG with the goal of contributing to a better understanding and correlation of installed performance predictions of highly integrated innovative intake designs. In a parametric study the combined effects of boundary layer ingestion and an S-shaped intake diffuser on total pressure recovery and distortion at the engine face were investigated as a function of Mach number, Reynolds number, boundary layer thickness, and intake mass flow ratio.