scholarly journals Surge and Stall Detection Using Acoustic Analysis for Gas Turbine Hybrid Cycles

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Keishaly Cabrera Cruz ◽  
Paolo Pezzini ◽  
Lawrence Shadle ◽  
Kenneth M. Bryden
Keyword(s):  
Gas Turbine ◽  
Natural Frequencies ◽  
Acoustic Analysis ◽  
General Nature ◽  
Acoustic Sensors ◽  
Frequency Range ◽  
Surge Margin ◽  
Compressor Surge ◽  
Surge Line ◽  
Transient Operations

Abstract Compressor dynamics were studied in a gas turbine—fuel cell hybrid power system having a larger compressor volume than traditionally found in gas turbine systems. This larger compressor volume adversely affects the surge margin of the gas turbine. Industrial acoustic sensors were placed near the compressor to identify when the equipment was getting close to the surge line. Fast Fourier transform (FFT) mathematical analysis was used to obtain spectra representing the probability density across the frequency range (0–5000 Hz). Comparison between FFT spectra for nominal and transient operations revealed that higher amplitude spikes were observed during incipient stall at three different frequencies, 900, 1020, and 1800 Hz. These frequencies were compared to the natural frequencies of the equipment and the frequency for the rotating turbomachinery to identify more general nature of the acoustic signal typical of the onset of compressor surge. The primary goal of this acoustic analysis was to establish an online methodology to monitor compressor stability that can be anticipated and avoided.

scholarly journals Surge and Stall Detection Using Acoustic Analysis for Gas Turbine Hybrid Cycles

2019 ◽  
Author(s):  
Keishaly Cabrera Cruz ◽  
Paolo Pezzini ◽  
Lawrence Shadle ◽  
Kenneth M. Bryden
Keyword(s):  
Gas Turbine ◽  
Natural Frequencies ◽  
Acoustic Analysis ◽  
General Nature ◽  
Acoustic Sensors ◽  
Frequency Range ◽  
Surge Margin ◽  
Compressor Surge ◽  
Surge Line ◽  
Transient Operations

Abstract Compressor dynamics were studied in a gas turbine – fuel cell hybrid power system having a larger compressor volume than traditionally found in gas turbine systems. This larger compressor volume adversely affects the surge margin of the gas turbine. Industrial acoustic sensors were placed near the compressor to identify when the equipment was getting close to the surge line. Fast Fourier transform (FFT) mathematical analysis was used to obtain spectra representing the probability density across the frequency range (0–5000 Hz). Comparison between FFT spectra for nominal and transient operations revealed that higher amplitude spikes were observed during incipient stall at three different frequencies, 900, 1020, and 1800 Hz. These frequencies were compared to the natural frequencies of the equipment and the frequency for the rotating turbomachinery to identify more general nature of the acoustic signal typical of the onset of compressor surge. The primary goal of this acoustic analysis was to establish an online methodology to monitor compressor stability that can be anticipated and avoided.

Compressor Instability Analysis Within a Hybrid System Subject to Cycle Uncertainties

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Alessandra Cuneo ◽  
Alberto Traverso ◽  
Aristide F. Massardo
Keyword(s):  
Fuel Cell ◽  
Gas Turbine ◽  
Hybrid System ◽  
Stochastic Analysis ◽  
High Speed ◽  
Operating Conditions ◽  
Operational Parameters ◽  
Surge Margin ◽  
Speed Range ◽  
Compressor Surge

The dynamic modeling of energy systems can be used for different purposes, obtaining important information both for the design phase and control system strategies, increasing the confidence during experimental phase. Such analysis in dynamic conditions is generally performed considering fixed values for both geometrical and operational parameters such as volumes, orifices, but also initial temperatures, pressure. However, such characteristics are often subject to uncertainty, either because they are not known accurately or because they may depend on the operating conditions at the beginning of the relevant transient. With focus on a gas turbine fuel cell hybrid system (HS), compressor surge may or may not occur during transients, depending on the aforementioned cycle characteristics; hence, compressor surge events are affected by uncertainty. In this paper, a stochastic analysis was performed taking into account an emergency shut-down (ESD) in a fuel cell gas turbine HS, modeled with TRANSEO, a deterministic tool for the dynamic simulations. The aim of the paper is to identify the main parameters that impact on compressor surge margin. The stochastic analysis was performed through the response sensitivity analysis (RSA) method, a sensitivity-based approximation approach that overcomes the computational burden of sampling methods. The results show that the minimum surge margin occurs in two different ranges of rotational speed: a high-speed range and a low-speed range. The temperature and geometrical characteristics of the pressure vessel, where the fuel cell is installed, are the two main parameters that affect the surge margin during an emergency shut down.

scholarly journals The Prediction of Surge Margins During Gas Turbine Transients

1985 ◽  
Author(s):  
N. R. L. Maccallum ◽  
P. Pilidis
Keyword(s):  
Boundary Layer ◽  
Gas Turbine ◽  
Thermal Effects ◽  
Adiabatic Flow ◽  
Surge Margin ◽  
Boundary Layer Development ◽  
Surge Line ◽  
Layer Development

This paper describes how allowance for the thermal effects of non-adiabatic flow, altered boundary layer development, changes in tip clearances and changes in seal clearances have been incorporated into a general gas turbine transient program. This program has been applied to a two-spool bypass engine. Revised predictions of surge margins in three common transients have been obtained. When the engine undergoes a “cold” acceleration, the thermal effects on the trajectory and on the surge line give a much increased proportion of unused surge margin in the H.P. Compressor, as compared to adiabatic predictions. In a “hot” acceleration this improvement is considerably reduced.

Analysis of Gas Turbine Performance in IGCC Plants Considering Compressor Operating Condition and Turbine Metal Temperature

2009 ◽  
Author(s):  
Y. S. Kim ◽  
J. J. Lee ◽  
K. S. Cha ◽  
T. S. Kim ◽  
J. L. Sohn ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Combined Cycle ◽  
Air Separation ◽  
Metal Temperature ◽  
Integrated Gasification Combined Cycle ◽  
Separation Unit ◽  
Gasification Process ◽  
Surge Margin ◽  
Compressor Surge ◽  
Integration Degree

An IGCC (integrated gasification combined cycle) plant couples a power block to a gasification block. The method of integrating a gas turbine with a gasification process is the major design option. Matching between the gas turbine and the air separation unit is especially important. This study analyzes the influences of IGCC design options on the operability and performance of the gas turbine. Another research focus is given to the estimation of the change of turbine metal temperature in the IGCC operating environment. For this purpose, a full off-design analysis of the gas turbine is used with the turbine blade cooling model. Four different syngas fuels are considered. As the integration degree becomes lower, the gas turbine power and efficiency increase. However, a lower integration degree causes a reduction of the compressor surge margin and overheating of the turbine metal. Only near 100% integration degree designs are almost free of those two problems. The syngas property also affects the gas turbine operation. As the heating value gets lower, the problems of surge margin reduction and metal overheating become more severe. Modifications of the compressor (adding a couple of stages) and the turbine (increasing gas path area) could solve the compressor surge problem. However, the turbine overheating problem still exists. In particular, the turbine modification is predicted to overheat turbine metal considerably.

Techno-Economic Evaluation of Commercially Available High Fogging Systems

2005 ◽  
Author(s):  
Sasha M. Savic ◽  
Katharina E. Rostek ◽  
Daniel K. Klaesson
Keyword(s):  
Gas Turbine ◽  
System Integration ◽  
Negative Impact ◽  
Water Injection ◽  
Hot Water ◽  
Safe Operation ◽  
Compressor Blades ◽  
Surge Margin ◽  
Compressor Surge ◽  
Pressure Swirl

High fogging (wet compression, spray inter-cooling) is a technology used for gas turbine (GT) power augmentation. By evaporative spray inter-cooling of the air during compression, which is the main physical effect associated with the HF, a 5–7% power boost of the GT (for each percent of injected water per mass of air) is achieved. HF of a gas turbine can be accomplished using different spray technologies. In this study three different, commercially available spray technologies — pressure-swirl, hot water injection and air-assisted atomization — are compared regarding both technical and economical benefits and risks. The comparison is based on droplet sizing results, system complexity, the feasibility of system integration into the GT’s control and plant operation concept, GT performance and operational and additional O&M costs. It is also known that high fogging carries certain risks to the safe operation of a GT, such as compressor blades erosion, reduction in compressor surge margin and cooling airflows. To minimize the negative impact of high fogging, it is therefore important to select the most appropriate high fogging system as well as to provide for its full engine integration.

Component Tests With a Model V84.3A Gas Turbine in the Siemens Test Facility in Berlin

2002 ◽  
Author(s):  
Christof Lechner ◽  
Bernward Mertens ◽  
Dieter Warnack ◽  
Dirk Weltersbach ◽  
Herwart Ho¨nen
Keyword(s):  
Flow Field ◽  
Gas Turbine ◽  
Field Measurements ◽  
Test Facility ◽  
Prediction System ◽  
Test Bed ◽  
Surge Margin ◽  
Compressor Surge ◽  
On Line ◽  
Flow Duct

In its Gas Turbine Development and Manufacturing Center in Berlin Siemens runs a test bed for gas turbine prototypes. Since the end of 1998, the new model V84.3A gas turbine has been undergoing tests at this facility. One focus of last year’s tests was on flow field measurements with pneumatic probes in the exit flow duct of the turbine at various load levels to characterize the flow in the diffuser and provide a data base. Another item was the further investigation of the compressor surge margin and the validation of a newly-developed on-line surge prediction system.

Experimental Investigations of Pressure Losses on the Performance of a Micro Gas Turbine System

2010 ◽  
Author(s):  
Jan Zanger ◽  
Axel Widenhorn ◽  
Manfred Aigner
Keyword(s):  
Steady State ◽  
Electric Power ◽  
Gas Turbine ◽  
Pressure Loss ◽  
System Stability ◽  
Pressure Losses ◽  
Micro Gas Turbine ◽  
Additional Pressure ◽  
Surge Margin ◽  
Compressor Surge

Pressure losses between compressor outlet and turbine inlet are a major issue of overall efficiency and system stability for a SOFC/MGT hybrid power plant system. The goal of this work is the detailed analysis of the effects of additional pressure losses on MGT performance in terms of steady-state and transient conditions. The experiments were performed at the micro gas turbine test rig at the German Aerospace Centre in Stuttgart using a butterfly control valve to apply additional pressure loss. The paper reports electric power and pressure characteristics at steady-state conditions, as well as, a new surge limit, which was found for the Turbec T100 micro gas turbine. Furthermore, the effects of additional pressure loss on compressor surge margin are quantified and a linear relation between relative surge margin and additional pressure loss is shown. For transient variation of pressure loss at constant turbine speed time delays are presented and a compensation issue of the commercial gas turbine controller is discussed. Finally, bleed-air blow-off and reduction of turbine outlet temperature are introduced as methods of increasing surge margin. It is quantified that both methods have a substantial effect on compressor surge margin. Furthermore, a comparison between both methods is given in terms of electric power output.

Meanline Calculation of Surge Margin Loss due to Inlet Flow Distortion

2020 ◽  
Author(s):  
Luca Menegozzo ◽  
Ernesto Benini
Keyword(s):  
Cfd Simulation ◽  
Numerical Models ◽  
Flow Distortion ◽  
Inlet Flow ◽  
Axial Compressors ◽  
Surge Margin ◽  
Compressor Surge ◽  
Surge Line ◽  
Inlet Flow Distortion ◽  
The Impact

Abstract In the present work, a methodology for the preliminary analysis of axial compressors operating under clean and distorted inflow conditions is discussed. A 1D mean-line solver has been developed, and the validation has been carried out under clean conditions considering the datasets of the subsonic Rolls-Royce HP9, as well as the transonic NASA Rotor 37 and NASA Rotor 67. Numerical results have been reported together with experimental data in terms of performance maps and spanwise distributions. The ARP1420 procedure and the parallel compressor theory have been implemented for the impact assessment of inlet flow distortion on the compressor surge line. A full-annulus CFD simulation of the NASA Rotor 37 has been carried out, in order to generate high-fidelity benchmark results. A 180° circumferential distortion has been considered as inlet boundary condition, and the surge line has been calculated using the two numerical models.

A Study of the Effect of Deterioration on Compressor Surge Margin in Constant-Speed, Single-Shaft Gas Turbine Engines

1986 ◽  
Author(s):  
Robert E. Dundas
Keyword(s):  
Gas Turbine ◽  
Constant Speed ◽  
Temperature Control System ◽  
Operating Line ◽  
Ambient Temperatures ◽  
Flow Capacity ◽  
Surge Margin ◽  
Compressor Surge ◽  
Compressor Map ◽  
Filter Clogging

A mathematical model of a constant-speed single-shaft gas turbine was devised using a typical compressor map. Performance calculations were performed at various ambient temperatures based on a standard temperature control system for a number of possible component deterioration modes. The effects on compressor operating line were determined. It was found that only two modes of deterioration; reduction of compressor flow capacity either through fouling or through erosion and closing of turbine nozzle diaphragms, moved the operating line toward surge. Inlet filter clogging must also be minimized in order to avoid surge because resulting distortion can induce stall and surge.

Compressor Instability Analysis Within an Hybrid System Subject to Cycle Uncertainties

2018 ◽  
Author(s):  
Alessandra Cuneo ◽  
Alberto Traverso ◽  
Aristide F. Massardo
Keyword(s):  
Fuel Cell ◽  
Gas Turbine ◽  
Hybrid System ◽  
Stochastic Analysis ◽  
Energy Systems ◽  
Operating Conditions ◽  
Transient Dynamic ◽  
Surge Margin ◽  
Speed Range ◽  
Compressor Surge

The transient/dynamic modeling of energy systems can be used for different purposes. Important information can be obtained and used for the design phase. The control system and strategies can be safely tested on transient/dynamic models in simulation, increasing the confidence during experimental phase. Furthermore, these models can be used to acquire useful information for safety case. The analysis of energy systems in dynamic conditions is generally performed considering fixed values for both geometrical and operational parameters such as volumes, orifices, but also initial temperatures, pressure, etc. However, such characteristics are often subject to uncertainty, either because they are not known accurately or because they may depend on the operating conditions at the beginning of the relevant transient. With focus on a micro-gas turbine fuel cell hybrid system, compressor surge may or may not occur during transients, depending on the aforementioned cycle characteristics; hence compressor surge events are affected by uncertainty. In this paper, a stochastic analysis was performed taking into account an emergency shut-down in a fuel cell gas turbine hybrid system, modelled with TRANSEO, a deterministic tool for the transient and dynamic simulations of energy systems. The aim of the paper is to identify the main parameters that impact on compressor surge margin. The stochastic analysis was performed through the RSA (Response Sensitivity Analysis) method, a sensitivity-based approximation approach that overcomes the computational burden of sampling methods such as MCS (Monte-Carlo Simulation). The results show that the minimum surge margin occurs in two different ranges of rotational speed: a high-speed range and a low-speed range, the latter being more sensitive for surge occurrence. The temperature and geometrical characteristic of the outer pressure vessel, where the fuel cell is installed, are the two main parameters that affect the surge margin during an emergency shut down.

Sign in / Sign up

Export Citation Format

Share Document