First reporting meeting of the DeSiReH project held in Germany

Professionals of TsAGI took part in the first reporting meeting within the DeSiReH 7FP EC (Design, Simulation and Flight Reynolds Number Testing for Advanced High Lift Solutions) project. In mid-September the Work Package Leaders gave their reports on the results of the first eighteen months of the project to the formal Commission. Dietrich Knörzer, the EC official representative in the area of Flight Physics, headed the Commission that was composed of two Technology Experts.

The project partners DLR (Germany), FOI (Sweden), EADS-CASA (Spain), CIRA (Italy), INTA (Spain) and ONERA (France) presented the main research results for the period under report. The results cover the tests of numerical methods that will be used when simulating non-stationary viscid gas fluids that emerge near the extended lift device wing under post-buckling angles of attack.

As a test pattern, experimental data was used which was obtained within the previous EUROLIF-2 project (the project devoted to wing lift enhancing methods).

The study proved that none of the currently existing RANS methods gives the correct description of the fluid physical peculiarities under post-buckling angles of attack. Due to this fact, the difference between the experimental data and computational ones that were obtained within EUROLIFT-2 and DeSiReH projects was extremely beneficial. Currently, TsAGI specialists are developing the non-stationary URANS-based method, i.e., Reynolds averaged non-stationary Navier-Stokes equations. This method will enable solving the targeted task with sufficient practical accuracy.

Special interest was paid to a discussion on optimization techniques. The representatives of Dassault Aviation (France) and CIRA (Italy) demonstrated that using the Adjoint approach makes it possible to apply, in optimizing cycles, state-of the art numerical methods based on Navier-Stokes equations. The partners made a consentient conclusion that the time for the nominal design point of geometry being optimized is not to surpass one hour, whereas currently the abovementioned time reaches ten hours.

DLR proposed to consider the numerical scheme entropic error influence upon the results when computing the aircraft drag coefficient. In a number of cases the abovementioned influence reaches 20% and requires particular attention as the entropic function is used as a restricting parameter during optimization (it is not to grow). The ONERA representatives touched upon the heat issue. For the second time they demanded control over the accuracy of obtaining the wing integral characteristics not only for the surface but for the shape as well. It is a rather severe test on conservatism of applied numerical schemes.

A celebration in honor of one of project partners took place after the seminar finalized its work: The IBK Company observed its 25th anniversary. Compliments and a souvenir were presented on behalf of Sergey Chernyshev, Executive Director of FSUE TsAGI.

«We note the heightened interest that was manifested to TsAGI on behalf of both the seminar participants and of the official establishment," said Sergei Bosnyakov, Deputy Head of propulsion aerodynamics department, the DeSiReH project Leader on behalf of TsAGI. «All this confirms the high regard for TsAGI in the 'European table of ranks'.»

In the photo: Sergey Bosnyakov (center) is giving the souvenir to IBK founder Dr. Krezschmar (left) and to IBK president Dr. Krier (right)