bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental and Numerical Investigation of Three-Dimensional Viscous Flows and Vortex Motion Inside an Annular Compressor Blade Row
Authors: Gallus H. E. , Hah C. , Schulz H. D. 
Published: March 2015

A detailed experimental and numerical investigation was carried out to examine the three-dimensional flow field, secondary flows and vortex motion in an annular compressor cascade.
Various flow visualizations near the blade surface and endwalls, wall static pressure and loss measurements, as well as hot-film and hot-wire measurements inside the blade boundary layers were performed at various flow rates to understand the complex flow phenomena. A Reynolds-averaged Navier-Stokes equation was solved to investigate the flow numerically.
The detailed comparison between measurement and numerical prediction indicates that the complex three-dimensional flow phenomena (corner stall, vortex motion, radial mixing, etc.) is very well predicted with the numerical method.
Second Generation Low-Emission Combustors for ABB Gas Turbines: Burner Development and Tests at Atmospheric Pressure
Authors: Sattelmayer Th. , Felchlin M. P. , Haumann J. , Hellat J. , Styner D. 
Published: March 2015

Based on fundamental research concerning swirling flows, including the vortex breakdown phenomenon, as well as on stability considerations of premixed flames, a second generation of low emission burners has been developed.
The lean premixing technique provides NOx-emissions below 25ppmv for natural gas. For liquid fuels the oxides of nitrogen are limited to 42ppmv (oil no. 2).
The novel burner technology will be applied to the well-known ABB silo combustor. As a first step the Conical Premix Burner will be used to retrofit the ABB type 11N. For the ABB gas turbine type 8 the design of a novel fully annular combustor is in progress.
Most of the conceptual work concerning burner aerodynamics and burner-burner interaction has been carried out on scaled-down burner- and combustor-models. For a second step a sector of the combustor in 1:1 scale has been tested at atmospheric pressure. Additional high pressure tests provide information about the combustor performance at engine conditions.
The present paper summarizes the results of the first two steps beginning with the early ideas in the conceptual phase up to the 1:1 tests which prove the low-NOx capability for both gaseous and liquid fuels under atmospheric pressure conditions.
Rolling Wear of Silicon Nitride Bearing Materials
Authors: Lucek John W. 
Published: March 2015

Rolling-contact fatigue test methods were used to measure the wear performance of several silicon nitride materials. Sintered, hot pressed and hot isostatically pressed materials exhibited wear rates ranging over three orders of magnitude. Hot isostatically pressed materials had the lowest wear rates. Despite the disparity in wear performance, all materials tested had useful rolling-contact fatigue lives compared to steel. Fatigue life estimates, failure modes, and rolling wear performance for theses ceramics are compared to M-50 steel.
This work highlights the rapid contact stress reductions that occur due to conformal wear in rolling-contact fatigue testing. Candidate bearing materials with unacceptably high wear rates may exhibit useful fatigue lives. Rolling contact bearing materials must possess useful wear and fatigue resistance. Proper performance screening of candidate bearing materials must describe the failure mode, wear rate, and the fatigue life. Guidelines for fatigue testing methods are proposed.
Unsteady Heat Transfer Measurements on a Rotating Gas Turbine Blade
Authors: Hilditch M. A. , Ainsworth R. W. 
Published: March 2015

Heat transfer measurements made on the rotor blade of a full stage model turbine operating at engine representative conditions are presented. The measurement technique of mounting thin film heat transfer gauges on enamel coated turbine blades enables the heat transfer rate to be measured across a frequency range of d.c. to 100kHz. The output is amplified using electronic circuits housed inside the shaft before transmission through a slipring and digital signal processing routines are used to calculate the heat transfer rate. A calibration experiment in which the gauge is pulsed with a laser beam is described in detail.
The results are compared with data from a previous two-dimensional simulation of wake-passing flow on the midheight section of the same blade. The mean heat transfer rate recorded in the two experiments shows reasonable agreement. Fluctuations in the unsteady heat transfer signal at NGV passing frequency are seen at the same locations in data from both experiments, however the magnitude of the fluctuations seen on the rotor are much smaller than those recorded in the two-dimensional simulation. Frequency spectra and correlation analysis of heat transfer traces recorded on the rotor are also presented.
A New Air Filtration System Concept for Space Limited Applications and Retrofits
Authors: Cuvelier L. , Belcher M. D. 
Published: March 2015

The need for adequate inlet air treatment for combustion gasturbines has been recognized for years. The benefit of high efficiency air filtration, mainly in high ambient dust environments does not require any further discussion as the shortfalls of the multi-stage static systems are known. The size of the conventional automatic pulse jet self cleaning airfilters is a serious handicap when considering upgrading/retrofitting outdated static filter systems or for any application in very limited spaces.
The new filter concept is described. It is an automatic Pulse Jet high efficiency self cleaning filter in which the major limiting factor of the previous design has been turned into an upgrading feature; the incoming air velocity direction basically eliminates the well-known pulsed dust re-entrainment. Other key design characteristics allow for capitalizing upon the reduced foot print area and justify the technical and economical replacement of the out-of-date filters with no or minor changes to the support structure. The system can in certain cases be incorporated within the old filterhouse itself.
Additional interesting features are discussed, supported by laboratory test results and field data from units operating in various environmental conditions.
Direct Heat Cogeneration Applications for Kaolin Producers
Authors: Hill Jane P. 
Published: March 2015

Direct heat cogeneration using gas turbines presents an unusually attractive means of supplying two end products when both are required simultaneously. Most cogeneration applications involve steam as the thermal end product. While steam has many industrial and commercial uses, the conversion of thermal output to usable steam involves losses in the heat recovery steam generator (HRSG). When the heat rejected by a gas turbine can be used directly, system losses can be minimized. One such application exists in the kaolin industry.
Kaolin is a white alumina-silicate clay used in many products, including paper, medicines, plastics and paints. One step in producing kaolin requires large spray dryers, the heat for which can be supplemented by cogeneration.
This study outlines conditions necessary to achieve economic viability with cogeneration and suggests ways to maximize economic benefits. Risks associated with cogeneration ventures are also discussed.
Energy Conservation With Catalytic Cracking in the Refinery
Authors: Najjar Yousef S. H. 
Published: March 2015

Fluidized-bed catalytic cracking is one of the most commonly used processes in petroleum refining to convert heavy high-boiling point components of crude oil into gasoline and distillate components.
An energy conservation measure for such a process, utilizes an axial flow compressor which furnishes air for combustion in the regenerator where the coke deposits are burned off the catalyst and also drives the catalyst through the system.
The flue gases from the regenerator are expanded in an expansion turbine which drives the compressor, whereas the excess energy is used to drive an electric generator. The exhaust gases are utilized further in a heat recovery boiler to produce process steam.
A parametric study involving variation of air pressure and expander inlet temperature using specially devised computer program, was used to analyse the performance of the proposed system. Furthermore, the system is economically evaluated and compared with the conventional cracking system using a gas turbine engine. The proposed system offers leading performance and economic advantages in comparison with the conventional one.
VATEMP: The Variable Area Turbine Engine Matching Program
Authors: Roy-Aikins J. E. A. , Palmer J. R. 
Published: March 2015

Variable geometry in key gas turbine components offers the advantage of either improving the internal performance of a component or of re-matching the engine cycle to alter the flow-temperature-pressure relationships. Future gas turbines are expected to use variable geometry components extensively if they are to overcome some of the problems encountered by present day engines at off-design conditions in order to give much more advanced performance. Greater attention is also being paid to the impact of installation losses on the performance of aircraft engines.
A computer program called VATEMP, herein described, has been developed capable of simulating the steady-state performance of arbitrary gas turbines with or without variable geometry in almost any gas path component. Results obtained from the program led to the conclusion that variable geometry components have the potential to improve significantly the off-design performance of gas turbines.
Aerothermal Boundary Layer Computation Including Strong Viscous-Inviscid Flow Interaction
Authors: Kulisa P. , Leboeuf F. , Klinger P. , Bernard J. 
Published: March 2015

The high temperature level reached at the exit of combustion chambers of modern aircraft engines and the practical limitations of advanced materials, demand efficient cooling of turbine blades. Optimization of the cooling requires an accurate prediction of aerodynamic losses and heat transfer on turbine blades.
A new two-dimensional compressible, aerothermal boundary layer code has been developed. The formulation includes strong viscous-inviscid interaction, which enhances the stability properties of the code. The boundary layer equations associated with the energy equation are solved with an implicit Keller-box scheme. Viscous-inviscid flow coupling is performed by adding an interaction equation which has an elliptic character. The complete system of equations is solved by a multi-pass procedure. This technique contributes to the stabilization of the method and allows the computation of regions with strong adverse pressure gradients, separation bubbles and injections in case of film cooling.
Comparisons between experimental and theoretical results are provided. Flow characteristics including heat transfer were computed for several cases such as flat plates with strong pressure gradients, and turbine blade boundary layers. Good agreement between computation and experiment is observed, demonstrating the high accuracy and robustness of the code.
Influence of Periodically Unsteady Wake Flow on the Flow Separation in Blade Channels
Authors: Dibelius G. H. , Ahlers E. 
Published: March 2015

The influence of periodically unsteady perturbations on the turbulent flow along the suction side of turbine blades is investigated in a test rig. The blade suction side is represented by a flat plate of 550 mm length. The pressure profile typically encountered in a turbine blade channel is generated by a curved wall opposite to the flat plate. The angle of the divergent part of the test channel and hence the pressure can be increased to induce flow separation on the flat plate. For simulation of the wakes from the upstream blade row the incoming flow is periodically disturbed by a wake generator consisting of five flat profiles arranged in front and parallel to the plate rotating with adjustable speed and phase angle.
A LDV with high spatial resolution is used to measure averaged and fluctuating components of the velocity inside the boundary layer flow down to a distance of y = 0,05 mm from the plate surface determining the boundary layer parameters as well as the wall shear stress. By Fourier analysis of the measured time related velocity distributions the stochastic and periodic parts of the overall turbulence are identified.
With a periodic wake flow the separation is shifted downstream as compared to the steady flow situation. This is due to the energization of the boundary layer flow associated with the conversion of periodic in stochastic parts of the turbulence. Conclusions resulting from the experimental findings for the theoretical understanding of the flow in turbine cascades are discussed in particular with respect to turbulence modelling.
Economic Considerations of Aircraft Turbines Manufacturing
Authors: Alonso Jacinto J. 
Published: March 2015

Aircraft gas turbines manufacturing started just fifty years ago; its production experienced one of the fastest evolutions of the world manufacturing industry. The purpose of this paper is to briefly describe some of the most important factors that currently affect the economic production of aircraft turbines.
Lead time for design and development of new turbines has increased with size and complexity, which makes the start of new projects much more difficult where a close liason is necessary between design and manufacturing departments. Interaction of so many activities will require a considerable coordination effort.
Estimating production costs and labour time standards will be also key factors for economic production of aircraft turbines. The effect of production quantity will be analysed using the learning curve approach which can be applied for direct and indirect labour time, material costs and material and labour burdens.
Testing at the US Navy’s Gas Turbine Systems Engineering Complex
Authors: Preisel John H. 
Published: March 2015

The United States Navy has developed a facility to support full scale testing of gas turbine propulsion systems. The first site at this facility is based on the gas turbine propulsion system for the newest class of surface combatants, the USS Arleigh Burke (DDG 51). The plant consists of two LM 2500 gas turbines, combined with a newly designed reduction gear, and supported by a gas turbine generator for electrical power.
This paper describes the design of the propulsion plant, and gives special emphasis to propulsion and electrical testing. The digital control system, and multiplexed communications system is described. Preliminary component, system and full scale integration test results are presented and discussed. The paper includes lessons learned from the installation of the propulsion train and the electrical systems. Finally, a brief description of the machinery control system software maintenance process, and our initial experiences with large scale software integration testing will be given.
This paper reaffirms the value of full scale systems integration testing. It also points out the fundamental role that electronics, computers, and software play in marine gas turbine systems.
Measurement and Calculation of End Wall Heat Transfer and Aerodynamics on a Nozzle Guide Vane in Annular Cascade
Authors: Harvey N. W. , Jones T. V. 
Published: March 2015

Detailed measurements of surface static pressures and heat transfer rates on the aerofoil and hub end wall of an annular nozzle guide vane (in the absence of a downstream rotor) are presented. Heat transfer rates have been measured using thin film gauges in an annular cascade in the Pyestock Isentropic Light Piston Cascade. Test Mach numbers, Reynolds numbers and cascade geometry are fully representative of engine conditions. The results of 3-D calculations of surface Mach number and 2-D calculations of aerofoil heat transfer are presented and compared with the measurements.
A new method of calculating end wall heat transfer using the axisymmetric analogue for three-dimensional boundary layers is described in detail. The method uses a 3-D Euler solver to calculate the inviscid surface streamlines along which heat transfer coefficients are calculated. The metric coefficient which describes the lateral convergence or divergence of the streamlines is used to include three-dimensional effects in the calculation. The calculated heat transfer rates compare well with the measured values. Reference is made to surface flow visualization in the interpretation of the results.
3D Flow Analysis in a Linear Cascade Using a Navier-Stokes Finite Element Code
Authors: Combes J. F. , Chabard J. P. , Metivet B. 
Published: March 2015

In order to solve industrial flow problems in complex geometries, a finite element code, N3S, has been developped at Electricité de France. For an incompressible unsteady flow, the Reynolds-averaged Navier-Stokes equations, with a k-ε turbulence modelling, are split into a set of equations for transport, for diffusion and a Generalized Stokes Problem. In this paper, we briefly describe the algorithms chosen to solve each step, the k-ε treatment and the boundary conditions (wall functions).
We present also the results of a flow calculation in a linear cascade at normal and high incidence and compare them with the measurements of Yamamoto (ASME papers 86-GT-185 and 88-GT-110). The main flow features and the secondary flows (i.e., the passage and the horseshoe vortex) are qualitatively well predicted by the code but some discrepancies exist in the prediction of the losses.
Ceramic Small Gas Turbine Technology Demonstrator
Authors: Bornemisza Tibor 
Published: March 2015

Requirements for increased power density, improved fuel economy, and rapid start demand higher turbine inlet temperatures and turbine wheel tip speeds, resulting in the need for materials with high strength to weight ratio at temperatures in excess of 2000°F. High performance ceramics appear to be the most promising substitutes for the current cobalt-nickel based superalloys.
The numerous advantages of ceramics are coupled with several unfavorable properties, such as the brittleness, the low reliability of the ceramic pans, and the lack of established design, manufacturing and inspection techniques. The development of reliable components requires a close cooperation between the user and the manufacturer of the high performance ceramics.
Sundstrand Power Systems has been involved with the development of ceramic gas turbine components since 1972. The current Research and Development effort involves the demonstration of ceramic turbine components operating at 2200°F turbine inlet temperature.
Silicon nitride turbine wheel and stationary components were designed and subjected to a series of tests in the Gemini small gas turbine modified for this purpose. Engine start to full speed in 2.5 seconds and continuous operation at 2300°F was demonstrated.
The successful testing of the ceramic turbine components demonstrated the feasibility of the currently available structural ceramic materials for non-flight-critical and unmanned turbine applications.
Nozzle Guide Vane Shock Wave Propagation and Bifurcation in a Transonic Turbine Rotor
Authors: Johnson A. B. , Oldfield M. L. G. , Rigby M. J. , Giles M. B. 
Published: March 2015

A study of the propagation of a Nozzle Guide Vane (NGV) trailing edge shock wave through a transonic turbine rotor passage is presented. The work was based on experimental tests carried out in the Isentropic Light Piston Tunnel in Oxford University using a rotating bar NGV shock wave simulator, together with schlieren photography and wide band width surface pressure and heat transfer rate measurements.
The study identifies a previously unexplained interaction between the incoming wave and the rotor leading edge, which causes the nucleation of a Vortical Bubble. This bubble has been shown to enhance the thermal loading on the early pressure surface of the blade. A method of controlling this bubble and heat loading is also considered.
A previously unseen “Lambda” interaction between the shock wave and the rotor pressure surface is also identified.
The Influences of Fintube Characteristics on the Manufacturing and Operation of Waste Heat Recovery Boilers (W.H.R.B.) Behind Turbines
Authors: Desmet P. A. 
Published: March 2015

The technological developments in the steam boiler field, induced by changes in the use of different fins and the need to save energy, has its consequential effects on the heat transfer techniques.
As the extended surface tube is one of the important components of the steam boilers and particularly of waste heat recovery boilers (WHRB) behind turbines, we want to draw the attention to recent developments in the field of finned tubes, opening new possibilities for the optimization of construction costs of WHRB on one hand and reducing the fouling problem by a new geometry of the helically wound fins on the other hand.
A New Method of Predicting the Performance of Gas Turbine Engines
Authors: Yonghong Wang 
Published: March 2015

This paper points out that the turbine performance computation method used widely at present in solving the performance of gas turbine engines is a numerically instable algorithm. So a new method, namely inverse algorithm, is proposed.
This paper then further proposes a new mathematical model of solving the stable performance of gas turbine engines. It has the features of not only being suitable for inverse algorithm for turbine performance, but also having less dimensions than existing models. So it has the advantages of high accuracy, rapid convergence, good stability, less computations, and so forth. It has been fully proven that the accuracy of the new model is much greater than that of the common model for gas turbine engines. Additionally, the time consumed for solving the new model is approximately 1 / 4 ∼ 1 / 10 of that for the common model. Therefore, it is valuable in practice.
MS3002 Advanced Tech Upgrade Application and Operating Experience
Authors: Grondahl Clayton M. , Guiler Marvin E. 
Published: March 2015

Modernization of MS3002 gas turbines produced by GE from 1951 to 1973 has been accomplished with the application of advanced technology components in a redesigned turbine hot section. Texas Eastern installed the first modernization package in 1986 and now have 10 units in service totalling more than 135,000 operating hours.
This paper presents the user’s motivation to refurbish 30 year old gas turbines, including details of the uprate installation and subsequent operating experience. Specifics of the advanced technology components in these units are provided including their impact on unit performance and reliability.
Coal-Derived Gas Utilization in Combined Gas-Steam Cycle Power Plants
Authors: Tuccillo R. , Fontana G. , Jannelli E. 
Published: March 2015

In this paper, a general analysis of combined gas-steam cycles for power plants firing with both hydrocarbons and coal derived gas is reported.
The purpose of this paper is to study the influence on power plants performance of different kind of fuels and to evaluate the most significant parameters of both gas and combined cycle.
Results are presented for plant overall efficiency and net specific work, steam to gas mass flow ratio, dimensionless gas turbine specific speed and diameter, CO2 emissions etc., as functions of gas cycle pressure ratio and of the combustion temperature.
Furthermore, for an existing power plant with a 120 MW gas turbine, the authors try to establish in which measure the combined cycle characteristic parameters, the gas turbine operating conditions, and the heat recovery steam generator efficiency, are modified by using synthetic fuels of different composition and calorific value.
The influence is also analyzed either of bottoming steam cycle saturation pressure or — in a dual pressure steam cycle — of dimensionless fraction of steam mass flow in high pressure stream.
The acquired results seem to constitute useful information on the criteria for the optimal design of a new integrated coal gasification combined cycle (IGCC) power plant.