The high-loaded centrifugal compressor blisk-type impeller, one of the main low-sized gas-turbine engine components, strongly affects engine efficiency. However, its design is a time-consuming and complex task for several reasons, including its high loading, the large number of structural and technological constraints, and the variety of requirements needed for application to a gas-turbine engine centrifugal compressor impeller (e.g., increased efficiency and strength, minimized weight requirements, etc.).
The imposition of several constraints for structure modification of the centrifugal wheels can improve one characteristic but can worsen others. The standard solution for this problem is to use an iterative approach, whereby the design process is reduced to a consistent set of impeller element design problem statements and decisions; these are separate for different analysis disciplines.
The main drawbacks to this approach are that it is labor intensive and can cause deterioration of the design quality because this procedure does not consider the design object as a unit. The present work considers a centrifugal compressor wheel design approach based on the use of an integrated multidisciplinary parameterized 3D model. This model includes a number of specialized sub-models that describe the necessary design areas as well as physical process features and phenomena occurring in the designed object. The model also realizes the integration and interaction of sub-models used in an integrated computing space.
The proposed approach allows the optimization of the structure based on several criteria, such as the mass of the wheel, stage efficiency, strength, economic indicators, etc. The result of multi-criteria optimization is not a single product design, but a set of optimal Pareto points, which describes a number of centrifugal wheel models. The optimal configuration is selected from this set, based on what is considered the most important criterion.
Optimization criteria may vary depending on the problem formulation, but the design technology, parameterization scheme, and choice of multidisciplinary integrated mathematical model are retained. Therefore, in the case of a product requirement correction, a new optimal design will require less time. In aggregate, with the nonlinear constrained optimization application, this approach reduces the total time of the design cycle, decreases development costs, and improves quality.
Performance Improvement of a 43 MW Class Gas Turbine Engine with Inlet Air Cooling
