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In this paper, a novel method for high temperature fatigue strength assessment of nickel superalloy turbine blades after operation at different times (303 and 473 h) was presented. The studies included destructive testing (fatigue testing at temperature 950 °C under cyclic bending load), non-destructive testing (Fluorescent Penetrant Inspection and Eddy Current method), and finite element modelling. High temperature fatigue tests were performed within load range from 5200 to 6600 N using a special self-designed blade grip attached to the conventional testing machine. The experimental results were compared with the finite element model generated from the ANSYS software. It was found that failure of turbine blades occurred in the area with the highest stress concertation, which was accurately predicted by the finite element (FE) model.

In order to take advantage of the sophisticated features offered by CAD and CAE packages for modeling and analysis during the design process, it is essential to build a bridge assuring a coherent link between these tools. Furthermore, this integration procedure must be automated so as to get rid of the repetitive costing effort. In this paper, a new automated procedure for the CAD/CAE integration, implemented for the parametric design and structural analysis of aircraft wing structures is presented. This procedure is based on the automation capacity available in modern computer aided tools via build-in basic programming languages as well as the capacity of the model data exchange. The geometric and numerical models can be controlled to generate a large variety of possible design cases through parameters introduced beforehand.

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Due to the development in computer technology, computational simulations have become indispensable for most engineering system design processes, particularly in aerospace applications. Performing a simulation-driven aerodynamic design optimization is a challenging task due to the computational expensiveness of high fidelity models, the considerable number of design parameters, the variety of disciplines that must be considered.. . etc. In this paper, the preliminary design of an aircraft wing through the use of a fully automated design environment, coupled with surrogate-based optimization, is presented. A parametric modeling framework was developed based on the seamless integration of several commercial software through built-in scripting languages. The design process goes through geometry modeling, Aerodynamic grid generation and flow solution which involves SIEMENS NX, ICEM CFD and FLUENT respectively. The optimization is made feasible using surrogate modeling techniques combined with a Sequential Quadratic Programing (SQP) algorithm.

This work contains the results of a modern helicopter construction analysis. It includes the comparison of almost seventy rotorcraft constructions in terms of size in line with EASA requirements – large and small helicopters. The helicopters are also divided because of a mission purpose. The proposed division for large aircrafts is: transport, multipurpose, attack and for small aircrafts: observation, training, and utility. The aircraft construction features are described. Average dimension values of airframes and rotors are shown. Helicopter rotor arrangements are presented in terms of an operational purpose. Next, the rotorcraft design inputs are described. The mathematical formulas for design inputs are given. The ratios are calculated and gathered for the compared aircrafts. Correlation between the analysed parameters is presented on charts. Design inputs are also presented in the paper as a function of MTOW. The function trends are determined to provide an evaluation tool for helicopter designers. In addition, the parameters are presented as possible optimisation variables.

Artykuł poświęcony jest budowie modelu łopatki turbiny wysokiego ciśnienia lotniczego silnika turbinowego. Przedstawiono ideę procesu projektowania łopatki turbiny i w tym obszarze parametrów własnych turbiny, które zawarto w analizie charakterystyk turbin. Przedstawiono charakterystyki dotyczące zmian głównych parametrów własnych turbiny, tzn. masowego natężenia przepływu, pracy jednostkowej, sprawności, obciążenia czy rozprężu turbiny od parametrów eksploatacyjnych. Przeanalizowano proces tworzenia modelu łopatki w oparciu o inżynierię odwrotną i parametryzację modelu dla potrzeb poniższej pracy. Algorytm tworzenia modelu parametrycznego został zbudowany w języku GRIP dla systemu Siemens NX. Zawarto najważniejsze zalety modelu parametrycznego wraz z matematycznym równoważnikiem wyboru wariantu procesu modelowania obiektu wirtualnego. Przedstawiono efekt budowy modelu w postaci wydruku łopatki w 3D. Uzyskany model będzie podstawą dalszych badań w zakresie charakterystykach aerodynamicznych dotyczącym pojedynczej łopatki, jak również palisady.

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