This paper describes the design concepts and object-oriented architecture of Onyx, an extensible domain framework for computational simulation of gas turbine engines. Onyx provides a flexible environment for defining, modifying and simulating the component-based gas turbine models described in Part I of this paper. Using advanced object-oriented technologies such as design patterns and framewor...

Gas turbine engine efficiency can be increased by the improvements of the cooling air system. In this study, gas turbine preswirl cooling system is computationally analyzed using a validated three-dimensional quasi-steady model. In the first phase of the study, the system is analyzed with respect to different operating conditions, for understanding its behavior. In this part, the dependence of ...

The effect of a regenerative heat exchanger in a gas turbine is analyzed using a regenerative Brayton cycle model, where all fluid friction losses in the compressor is quantified by an isentropic efficiency term and all global irreversibilities in the heat exchanger are taken into account by means of an effective efficiency. This analysis, which generalizes that reported by Gordon and Huleihil ...

A fuzzy system is developed using a linearized performance model of the gas turbine engine for performing gas turbine fault isolation from noisy measurements. By using a priori information about measurement uncertainties and through design variable linking, the design of the fuzzy system is posed as an optimization problem with low number of design variables which can be solved using the geneti...

Among the many requirements for the design of gas turbine engine components,understanding of the behaviour of these components and the alloys used to make themis fundamental in order to ensure structural integrity and safe operation of theengines. In this paper, the conventional Safe Life Approach is discussed togetherwith an overview of crack growth modelling used at Pratt it W...

Sensor selection optimization can lead to significant improvements in the controllability and observability of a dynamic system. The aim of this research is to investigate optimal or alternate measurement sets for aircraft gas turbine engine health parameter estimation. A brute force search for the best sensor set is too computationally expensive. Therefore, a Monte Carlo approach is used to pe...

This paper summarises the work of a 5-year research programme into the heat transfer within cavities adjacent to the main annulus of a gas turbine. The work has been a collaboration between several gas turbine manufacturers, also involving a number of universities working together. The principal objective of the study has been to develop and validate computer modelling methods of the cooling fl...

One of the options being examined in last decades in the development of environmentally sustainable, energy-efficient and lightweight vehicles is the replacement of piston engines by gas turbine engines, especially in hybrid vehicles. A lot of effort has been consistently put in design and production of concept hybrid automobiles powered by gas turbine engines by leading automobile producers su...

The effect of two heat additions, rather than one, in a gas turbine engine is analyzed from the second law of thermodynamics point of view. A regenerative Brayton cycle model is used for this study, and compared with other models of Brayton cycle. All fluid friction losses in the compressor and turbine are quantified by an isentropic efficiency term. The effect of pressure ratio, turbine inlet ...