Advanced Modeling of Fluid Thermodynamic Properties for Gas Turbine Performance Simulation

Abstract

This paper describes the structure of an advanced fluid thermodynamic model which has been developed for a novel advanced gas turbine simulation environment called PROOSIS. PROOSIS (PRopulsion Object Oriented SImulation Software) is part of the VIVACE-ECP (Value Improvement through a Virtual Aeronautical Collaborative Enterprise - European Cycle Programme) project. The main objective of the paper is to determine a way to achieve an accurate, robust and reliable fluid model. The results obtained demonstrate that accurate modeling of the working fluid is essential to avoid convergence problems of the thermodynamic functions thereby increasing the accuracy of calculated fluid properties. Additionally, the impact of accurately modeling fuel thermodynamic properties, at the point of the injection, is discussed.

Uncertainty in gas turbine thermo-fluid modelling and its impact on performance calculations and emissions predictions at aircraft system level

“…Nevertheless, fluid tabulations offer several key advantages that have been discussed extensively by Sethi et al [1,25].…”

“…A fluid model for an engine performance code comprises of thermodynamic functions to calculate the unknown local flow properties, at any point (inlet, outlet, or intermediate) of any gas turbine component provided one of a set of twelve compatible input options is satisfied [1]. It should be noted here that previous studies have revealed that the impact of the FAR u parameter can be neglected for gas turbine applications [33].…”

“…Conventionally, there are two approaches for implementing technical fluid models in gas turbine [1]) interpolated fluid tables or (b) from polynomial functions. Generating fluid model tables, either from polynomial relationships such as those described in references [7,11,21,22], and/or chemical equilibrium software such as CEA (chemical equilibrium with applications) [8], Gaseq [23], and CEC (chemical equilibrium composition) [24], is far more laborious and time consuming than directly implementing polynomial functions.…”

“…Accurate and reliable fluid modelling is essential for any gas turbine performance simulation software as it provides a robust foundation for building advanced multi-disciplinary modelling capabilities [1]. Caloric properties for generic and semi generic gas turbine performance simulation codes can be calculated at various levels of fidelity; selection of the fidelity level is dependent upon the objectives of the simulation and execution time constraints.…”

Аналитическое Определение Истинной Удельной Изобарной Теплоёмкости Компонент Воздуха И Продуктов Сгорания С Учётом Влияния Температуры И Давления И Эффекта Термической Диссоциации

“…С другой стороны накопленный для различных газов экспериментальный материал зависимости р c от температуры и давления дал возможность работы с таблицами-массивами [19], интерполируя в онлайн режиме значение р c между узлами по формуле Тейлора для функции двух переменных [20]. Такой способ определения р c f (T; p)  требует хранения массивов и наличия специальных подпрограмм, работающих с ним, что не всегда удобно.…”