The numerical simulation of flows is an indispensable method for all aerodynamic development work on the aircraft. It is a key technology for improving the efficiency, environmental compatibility and safety of newly developed aircrafts and thus contributes significantly to the competitiveness of the German aviation industry.
The design process of future airplanes is supposed to base mainly on simulation data. The numerical air flow simulation is a key technology for that. Therefore, it is necessary to handle upcoming errors and uncertainties in a reliable way and try to minimize them.
Based on the simulation programmes developed in the previous projects MEGAFLOW and MEGADESIGN, the MUNA project will develop and deploy methods by which the uncertainties occurring in forecasting air flows can be analysed, quantified and minimised.
Priorities of the project are:
- the identification of sources of uncertainty and quantifying characteristic errors,
- analysis of sensitivities and the calculation of error ranges,
- the development of methods and procedures to minimize dominant fault,
- verification the methods and proof of reliability.
Building on the MEGAFLOW and MEGADESIGN project teams, MUNA concentrates the national research activities in numerical aerodynamics in an efficient network and thus strengthens the German position in the European context.
The MUNA project was divided into several work packages:
- WP1: Management
- WP2: Identify and quantify uncertainties.
- WP3: Methods for analysis and estimation of uncertainties
- WP4: handling with and minimization of uncertainties
- WP5: Testing of the new methods
According to the different work packages, the following milestones have been achieved:
- Report of the DLR: Identification and classification of uncertainties and error sources (WP2)
- Test cases were specified (WP2)
- Report on the findings about quantification and classification of error sources (WP2)
- Error estimate about the variance and coefficients (WP3)
- Alternative strategy: Calculation method of a superior residuum for the goal-oriented adaptation (WP3)
- Error estimate for the turbulence model (WP3)
- Goal-oriented adaptation was extended on multiple objective functions (WP3).
- Analytical methods for the identification of errors on discretization available (WP4)
- Tool extension for quality control of adapted hybrid grids (WP4)
- Extensions and Improvements of the adaptation module for the TAU code (WP4)
- MUNA best-Practice-Guide (WP4)
- Reliable assessment of uncertainties thanks to sensitivity analysis (WP5)
Findings of the study are published by a final report (German only), which is available online via the Technical Information Library (TIB) of the Hannover University: http://edok01.tib.uni-hannover.de/edoks/e01fb13/740144332.pdf