A gas turbine diagnostic approach with transient measurements

Most gas turbine performance analysis based diagnostic methods use the information from steady state measurements. Unfortunately, steady state measurement may not be obtained easily in some situations, and some types of gas turbine fault contribute little to performance deviation at steady state operating conditions but significantly during transient processes. Therefore, gas turbine diagnostics with transient measurement is superior to that with steady state measurement. In this paper, an accumulated deviation is defined for gas turbine performance parameters in order to measure the level of performance deviation during transient processes. The features of the accumulated deviation are analysed and compared with traditionally defined performance deviation at a steady state condition. A non-linear model based diagnostic method, combined with a genetic algorithm (GA), is developed and applied to a model gas turbine engine to diagnose engine faults by using the accumulated deviation obtained from transient measurement. Typical transient measurable parameters of gas turbine engines are used for fault diagnostics, and a typical slam acceleration process from idle to maximum power is chosen in the analysis. The developed diagnostic approach is applied to the model engine implanted with three typical single-component faults and is shown to be very successful.

Download Full-text

A Propeller Model for Steady-State and Transient Performance Prediction of Turboprop and Counter-Rotating Open Rotor Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4038814 ◽

2018 ◽

Vol 140 (7) ◽

Cited By ~ 1

Author(s):

Vinícius Tavares Silva ◽

Cleverson Bringhenti ◽

Jesuino Takachi Tomita ◽

Anderson Frasson Fontes

Keyword(s):

Steady State ◽

Gas Turbine ◽

Performance Prediction ◽

Pitch Angle ◽

Operating Conditions ◽

Performance Estimation ◽

Transient Performance ◽

Turbine Performance ◽

Constant Pitch ◽

Open Rotor

This paper describes a methodology used for propeller performance estimation, which was implemented in an in-house modular program for gas turbine performance prediction. A model based on subsonic generic propeller maps and corrected for compressibility effects, under high subsonic speeds, was proposed and implemented. Considering this methodology, it is possible to simulate conventional turboprop architectures and counter-rotating open rotor (CROR) engines in both steady-state and transient operating conditions. Two simulation scenarios are available: variable pitch angle propeller with constant speed; or variable speed propeller with constant pitch angle. The simulations results were compared with test bench data and two gas turbine performance commercial software packages were used to fulfill the model validation for conventional turboprop configurations. Furthermore, a direct drive CROR engine was simulated using a variable inlet guide vanes (VIGV) control strategy during transient operation. The model has shown to be able to provide several information about propeller-based engine performance using few input data, and a comprehensive understanding on steady-state and transient performance behavior was achieved in the obtained results.

Download Full-text

Steady State Measurement of Oxygenation Capacity

Water Science & Technology ◽

10.2166/wst.1985.0139 ◽

1985 ◽

Vol 17 (2-3) ◽

pp. 303-311

Author(s):

Kees de Korte ◽

Peter Smits

Keyword(s):

Steady State ◽

Activated Sludge ◽

Plug Flow ◽

Usual Method ◽

Steady State Method ◽

State Measurement ◽

Flow Systems ◽

Air System ◽

State Method ◽

Steady State Measurement

The usual method for OC measurement is the non-steady state method (reaeration) in tapwater or, sometimes, in activated sludge. Both methods are more or less difficult and expensive. The steady state method with activated sludge is presented. Fundamentals are discussed. For complete mixed aeration tanks, plug flow systems with diffused air aeration and carousels the method is described more in detail and the results of measurements are presented. The results of the steady state measurements of the diffused air system are compared with those of the reaeration method in tapwater. The accuracy of the measurements in the 3 systems is discussed. Measurements in other aeration systems are described briefly. It is concluded that the steady state OC measurement offers advantages in comparison with the non-steady state method and is useful for most purposes.

Download Full-text

Non-steady-state measurement of in vivo receptor binding with positron emission tomography: "dose-response" analysis

Journal of Neuroscience ◽

10.1523/jneurosci.09-07-02344.1989 ◽

1989 ◽

Vol 9 (7) ◽

pp. 2344-2352 ◽

Cited By ~ 18

Author(s):

JS Perlmutter ◽

MR Kilbourn ◽

MJ Welch ◽

ME Raichle

Keyword(s):

Positron Emission Tomography ◽

Steady State ◽

Receptor Binding ◽

Emission Tomography ◽

Response Analysis ◽

Positron Emission ◽

State Measurement ◽

In Vivo Receptor Binding ◽

Steady State Measurement

Download Full-text

Marine Gas Turbine Performance Model for More Electric Ships

Volume 4: Cycle Innovations; Fans and Blowers; Industrial and Cogeneration; Manufacturing Materials and Metallurgy; Marine; Oil and Gas Applications ◽

10.1115/gt2011-46101 ◽

2011 ◽

Cited By ~ 1

Author(s):

George M. Koutsothanasis ◽

Anestis I. Kalfas ◽

Georgios Doulgeris

Keyword(s):

Gas Turbine ◽

Fuel Consumption ◽

Diesel Engines ◽

Gas Turbines ◽

Electric Propulsion ◽

Operating Conditions ◽

Prime Mover ◽

Creep Life ◽

Hull Fouling ◽

Turbine Performance

This paper presents the benefits of the more electric vessels powered by hybrid engines and investigates the suitability of a particular prime-mover for a specific ship type using a simulation environment which can approach the actual operating conditions. The performance of a mega yacht (70m), powered by two 4.5MW recuperated gas turbines is examined in different voyage scenarios. The analysis is accomplished for a variety of weather and hull fouling conditions using a marine gas turbine performance software which is constituted by six modules based on analytical methods. In the present study, the marine simulation model is used to predict the fuel consumption and emission levels for various conditions of sea state, ambient and sea temperatures and hull fouling profiles. In addition, using the aforementioned parameters, the variation of engine and propeller efficiency can be estimated. Finally, the software is coupled to a creep life prediction tool, able to calculate the consumption of creep life of the high pressure turbine blading for the predefined missions. The results of the performance analysis show that a mega yacht powered by gas turbines can have comparable fuel consumption with the same vessel powered by high speed Diesel engines in the range of 10MW. In such Integrated Full Electric Propulsion (IFEP) environment the gas turbine provides a comprehensive candidate as a prime mover, mainly due to its compactness being highly valued in such application and its eco-friendly operation. The simulation of different voyage cases shows that cleaning the hull of the vessel, the fuel consumption reduces up to 16%. The benefit of the clean hull becomes even greater when adverse weather condition is considered. Additionally, the specific mega yacht when powered by two 4.2MW Diesel engines has a cruising speed of 15 knots with an average fuel consumption of 10.5 [tonne/day]. The same ship powered by two 4.5MW gas turbines has a cruising speed of 22 knots which means that a journey can be completed 31.8% faster, which reduces impressively the total steaming time. However the gas turbine powered yacht consumes 9 [tonne/day] more fuel. Considering the above, Gas Turbine looks to be the only solution which fulfills the next generation sophisticated high powered ship engine requirements.

Download Full-text

Comparison of Coriolis and Turbine Type Flow Meters for Fuel Measurement in Gas Turbine Testing

Volume 1: Aircraft Engine; Marine; Turbomachinery; Microturbines and Small Turbomachinery ◽

10.1115/93-gt-070 ◽

1993 ◽

Author(s):

J. D. MacLeod ◽

W. Grabe

Keyword(s):

Steady State ◽

Gas Turbine ◽

Mass Flow ◽

Gas Turbines ◽

Gas Turbine Engine ◽

Turbine Engine ◽

Turbine Flowmeter ◽

Turbine Performance ◽

Coriolis Flowmeter ◽

Project Objectives

The Machinery and Engine Technology (MET) Program of the National Research Council of Canada (NRCC) has established a program for the evaluation of sensors to measure gas turbine engine performance accurately. The precise measurement of fuel flow is an essential part of steady-state gas turbine performance assessment. Prompted by an international engine testing and information exchange program, and a mandate to improve all aspects of gas turbine performance evaluation, the MET Laboratory has critically examined two types of fuel flowmeters, Coriolis and turbine. The two flowmeter types are different in that the Coriolis flowmeter measures mass flow directly, while the turbine flowmeter measures volumetric flow, which must be converted to mass flow for conventional performance analysis. The direct measurement of mass flow, using a Coriolis flowmeter, has many advantages in field testing of gas turbines, because it reduces the risk of errors resulting from the conversion process. Turbine flowmeters, on the other hand, have been regarded as an industry standard because they are compact, rugged, reliable, and relatively inexpensive. This paper describes the project objectives, the experimental installation, and the results of the comparison of the Coriolis and turbine type flowmeters in steady-state performance testing. Discussed are variations between the two types of flowmeters due to fuel characteristics, fuel handling equipment, acoustic and vibration interference and installation effects. Also included in this paper are estimations of measurement uncertainties for both types of flowmeters. Results indicate that the agreement between Coriolis and turbine type flowmeters is good over the entire steady-state operating range of a typical gas turbine engine. In some cases the repeatability of the Coriolis flowmeter is better than the manufacturers specification. Even a significant variation in fuel density (10%), and viscosity (300%), did not appear to compromise the ability of the Coriolis flowmeter to match the performance of the turbine flowmeter.

Download Full-text

Comparison of Linear and Non-Linear Gas Turbine Performance Diagnostics

Volume 1: Turbo Expo 2003 ◽

10.1115/gt2003-38518 ◽

2003 ◽

Cited By ~ 6

Author(s):

Ph. Kamboukos ◽

K. Mathioudakis

Keyword(s):

Gas Turbine ◽

Condition Monitoring ◽

Theoretical Background ◽

Diagnostic Methods ◽

Turbine Performance ◽

Different Types ◽

Non Linear ◽

Computational Procedures ◽

Monitoring And Diagnostics ◽

Performance Diagnostics

The features of linear performance diagnostic methods are discussed, in comparison to methods based on full non-linear calculation of performance deviations, for the purpose of condition monitoring and diagnostics. First, the theoretical background of linear methods is overviewed to establish a relationship to the principles used by non-linear methods. Then computational procedures are discussed and compared. The effectiveness of determining component performance deviations by the two types of approaches is examined, on different types of diagnostic situations. A way of establishing criteria to define whether non-linear methods have to be employed is presented. An overall assessment of merits or weaknesses of the two types of methods is attempted, based on the results presented in the paper.

Download Full-text