Combined effects of stress and temperature on hydrogen diffusion in non-hydride forming alloys applied in gas turbines

Hydrogen plays a vital role in the utilisation of renewable energy, but ingress and diffusion of hydrogen in a gas turbine can induce hydrogen embrittlement on its metallic components. This paper aims to investigate the hydrogen transport in a non-hydride forming alloy such as Alloy 690 used in gas turbines inspired by service conditions of...

Gas Turbines Power Regulation Subject to Actuator Constraints, Disturbances and Measurement Noises

An accurate understanding of the output power functionality in gas turbines concerning the fuel, inlet valve status and other parameters can provide a general overview of the turbine's performance. In this study, the problem of practical power regulation in gas turbines is investigated in the simultaneous presence of actuator constraints,...

A singular values approach in helicopter gas turbine engines flight testing analysis

The process of empirical models evaluation is at the core business of experimental flight-testing data analysis. Accurate and convenient flight-testing of helicopter engine(s) available power is crucial for predicting the total helicopter performance. Common practice in estimation of in-flight helicopter gas turbine engine power consists of a...

Corrosion-Fatigue Failure of Gas-Turbine Blades in an Oil and Gas Production Plant

This paper investigates the root cause of a failure in gas-turbine blades, made of Nimonic-105 nickel-based superalloy. The failure was reported in two blades in the second stage of a turbine-compressor of a gas turbine in the hot section. Two failed blades were broken from the root and from the airfoil. The failure took place after 20 k h of...

Flameless combustion and its potential towards gas turbines

Since its discovery, the Flameless Combustion (FC) regime has been seen as a promising alternative combustion technique to reduce pollutant emissions of gas turbine engines. This combustion mode is often characterized by well-distributed reaction zones, which can potentially decrease temperature gradients, acoustic oscillations and,...

Helicopter Gas Turbine Engine Performance Analysis: A Multivariable Approach

Helicopter performance relies heavily on the available output power of the engine(s) installed. A simplistic single-variable analysis approach is often used within the flight-testing community to reduce raw flight-test data in order to predict the available output power under different atmospheric conditions. This simplistic analysis approach...

Generic Analysis Methods for Gas Turbine Engine Performance: The development of the gas turbine simulation program GSP

Numerical modelling and simulation have played a critical role in the research and development towards today’s powerful and efficient gas turbine engines for both aviation and power generation. The simultaneous progress in modelling methods, numerical methods, software development tools and methods, and computer platform technology has provided...

Smart Operation of Gas Turbine Combined Cycle Plants: Prediction and Improvement of Thermal Efficiency at Part Load

This thesis investigates various operational aspects of Gas Turbine Combined Cycle Power Plants (GTCC). GTCC power plants are expected to play an increasingly important role in the balancing of supply and demand in the electricity grid. Although originally meant for predominantly base load operation with high efficiencies, market circumstances,...

Generic methods for aero-engine exhaust emission prediction

In the thesis, generic methods have been developed for aero-engine combustor performance, combustion chemistry, as well as airplane aerodynamics, airplane and engine performance. These methods specifically aim to support diverse emission prediction studies coupled with airplane and engine simulation. Models for the engine exhaust composition can...