Windage Heating of Air Passing Through Labyrinth Seals

1994 ◽  
Author(s):  
J. A. Millward ◽  
M. F. Edwards
Keyword(s):  
High Speed ◽  
Cooling System ◽  
Momentum Balance ◽  
Viscous Drag ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Secondary Cooling ◽  
Labyrinth Seals ◽  
Accurate Temperature ◽  
Cooling Air

The viscous drag on rotating components in gas turbine engines represents both a direct loss of power from the cycle and an input of heat into the secondary (cooling) air system. Hotter cooling air in turn means increased flow requirements. The effects of windage on performance are therefore compounded. To facilitate accurate temperature predictions of highly stressed components, information is needed on windage characteristics of all elements in the secondary cooling system. Much information is available in the literature for discs, cones, cylinders, bolts etc but little has been published on windage heating in high speed seals. Results are presented for experiments carried out (at representative non-dimensional conditions) on different designs of labyrinth seals. The results are compared with values calculated from the simple momentum balance theory suggested by McGreeham and Ko (1989) and with several values determined from CFD analysis.

Windage Heating of Air Passing Through Labyrinth Seals

1996 ◽  
Vol 118 (2) ◽  
pp. 414-419 ◽  
Author(s):  
J. A. Millward ◽  
M. F. Edwards
Keyword(s):  
High Speed ◽  
Cooling System ◽  
Momentum Balance ◽  
Viscous Drag ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Secondary Cooling ◽  
Labyrinth Seals ◽  
Accurate Temperature ◽  
Cooling Air

The viscous drag on rotating components in gas turbine engines represents both a direct loss of power from the cycle and an input of heat into the secondary (cooling) air system. Hotter cooling air in turn means increased flow requirements. The effects of windage on performance are therefore compounded. To facilitate accurate temperature predictions of highly stressed components, information is needed on windage characteristics of all elements in the secondary cooling system. Much information is available in the literature for disks, cones, cylinders, bolts, etc., but little has been published on windage heating in high-speed seals. Results are presented for experiments carried out (at representative nondimensional conditions) on different designs of labyrinth seals. The results are compared with values calculated from the simple momentum balance theory suggested by McGreeham and Ko [13] and with several values determined from CFD analysis.

scholarly journals Leakage and Power Loss Test Results for Competing Turbine Engine Seals

2004 ◽  
Author(s):  
Margaret P. Proctor ◽  
Irebert R. Delgado
Keyword(s):  
High Temperature ◽  
Power Loss ◽  
High Speed ◽  
Operating Conditions ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Test Results ◽  
Test Rig ◽  
Labyrinth Seals ◽  
Turbine Engine

Advanced brush and finger seal technologies offer reduced leakage rates over conventional labyrinth seals used in gas turbine engines. To address engine manufactures’ concerns about the heat generation and power loss from these contacting seals, brush, finger, and labyrinth seals were tested in the NASA High Speed, High Temperature Turbine Seal Test Rig. Leakage and power loss test results are compared for these competing seals for operating conditions up to 922 K (1200 °F) inlet air temperature, 517 KPa (75 psid) across the seal, and surface velocities up to 366 m/s (1200 ft/s).

Renovation features of powder high-speed steels broaches with plazma hardening

2021 ◽  
pp. 82-85
Author(s):  
A.S. Politov ◽  
R.R. Latypov
Keyword(s):  
Gas Turbine ◽  
Comparative Studies ◽  
High Speed ◽  
Atmospheric Plasma ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Cold Atmospheric Plasma ◽  
Plasma Hardening

The comparative studies results of the durability of cutting properties of new and restored by regrinding and repeated plasma hardening with the application of multi-layer Si—O—C—N nanocoating system (PECVD by cold atmospheric plasma) powder high — speed steels broaches teeth for the processing of hard-to-process materials profilecomposite gas-turbine engines components are presented.

Marine Operation of Gas Turbine Engines and Waterjet Pumps for Small Passenger Vessels

1979 ◽  
Author(s):  
S. M. Kowleski ◽  
C. D. Harrington
Keyword(s):  
Gas Turbine ◽  
San Francisco ◽  
High Speed ◽  
San Francisco Bay ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Golden Gate ◽  
Operational Problem ◽  
Golden Gate Bridge ◽  
Selection Of

This paper describes the planning, developmental, equipment selection and operational problem phases of the high-speed ferry system presently being operated on San Francisco Bay by the Golden Gate Bridge, Highway and Transportation District. The reasons for the selection of the vessel propulsion package consisting of gas turbine engines and waterjet pumps are discussed in some detail. Most importantly, the paper covers the problems experienced to date with this equipment in continuous marine operation.

Relative Cooling: Part II — Design Considerations and Efficiency

2001 ◽  
Author(s):  
Sandu Constantin ◽  
Dan Brasoveanu
Keyword(s):  
Gas Turbine ◽  
Thermal Efficiency ◽  
Cooling System ◽  
High Reliability ◽  
Difficult Problem ◽  
Turbine Engines ◽  
Air Cooling ◽  
Gas Turbine Engines ◽  
Coolant Pump ◽  
Cooling Systems

Abstract Cooling systems with liquid for gas turbine engines that use the relative motion of the engine stator with respect to the rotor for actuating the coolant pump can be encapsulated within the engine rotor. In this manner, the difficult problem of sealing stator/rotor interfaces at high temperature, pressure and relative velocity is circumvented. A first generation of such cooling systems could be manufactured using existing technologies and would boost the thermal efficiency of gas turbine engines by more than 2% compared to recent designs that use advanced air-cooling methods. Later, relative cooling systems could increase the thermal efficiency of gas turbine engines by 8%–11% by boosting the temperatures at turbine inlet to stoichiometric levels and recovering most of the heat extracted from turbine during cooling. The appreciated high reliability of this cooling system will allow widespread use for aerospace propulsion.

scholarly journals The Basics of Powder Lubrication in High-Temperature Powder-Lubricated Dampers

1991 ◽  
Author(s):  
Hooshang Heshmat ◽  
James F. Walton
Keyword(s):  
High Temperature ◽  
High Speed ◽  
Basic Mechanism ◽  
Test Facility ◽  
Experimental Program ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Powder Lubrication ◽  
Basic Features ◽  
Selection Of

The objective of this investigation is to develop a novel powder-lubricated rotor bearing system damper concept for use in high-temperature, high-speed rotating machinery such as advanced aircraft gas turbine engines. The approach discussed herein consists of replacing a conventional oil lubrication or frictional damper system with a powder lubrication system that uses the process particulates or externally-fed powder lubricant. Unlike previous work in this field, this approach is based on the postulate of the quasi-hydrodynamic nature of powder lubrication. This postulate is deduced from past observation and present verification that there are a number of basic features of powder flow in narrow interfaces that have the characteristic behavior of fluid film lubrication. In addition to corroborating the basic mechanism of powder lubrication, the conceptual and experimental work performed in this program provides guidelines for selection of the proper geometries, materials and powders suitable for this tribological process. The present investigation describes the fundamentals of quasi-hydrodynamic powder lubrication and defines the rationale underlying the design of the test facility. The performance and the results of the experimental program present conclusions reached regarding design requirements as well as the formulation of a proper model of quasi-hydrodynamic powder lubrication.

scholarly journals Generalized High Speed Simulation of Gas Turbine Engines

1990 ◽  
Author(s):  
Nanahisa Sugiyama
Keyword(s):  
Real Time ◽  
Gas Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Power Plants ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Jet Engines ◽  
Industrial Gas Turbine ◽  
High Degree

This paper describes a real-time or faster-than-real-time simulation of gas turbine engines, using an ultra high speed, multi-processor digital computer, designated the AD100. It is shown that the frame time is reduced significantly without any loss of fidelity of a simulation. The simulation program is aimed at a high degree of flexibility to allow changes in engine configuration. This makes it possible to simulate various types of gas turbine engines, including jet engines, gas turbines for vehicles and power plants, in real-time. Some simulation results for an intercooled-reheat type industrial gas turbine are shown.

MULTIPARAMETRIC DIAGNOSTICS OF GAS TURBINE ENGINES

2021 ◽  
Vol 156 (A2) ◽  
Author(s):  
J Sinay ◽  
A Tompos ◽  
M Puskar ◽  
V Petkova
Keyword(s):  
Gas Turbine ◽  
High Speed ◽  
Technical Condition ◽  
Diagnostic Methods ◽  
Turbine Engines ◽  
Technical Diagnostics ◽  
Suitable Model ◽  
Gas Turbine Engines ◽  
Advantages And Disadvantages ◽  
The Matrix

This article addresses the issue of diagnostics and maintenance of Gas Turbine Engines which are located in high Speed Ferries, Cruisers, Frigates, Corvettes, etc. Assurance of reliable operation can be performed only by using correct diagnostic methods and procedures of monitoring the condition of the devices and by selecting the correct strategy of maintenance. The issue of monitoring the technical condition of Gas Turbine Engines is treated through multiparametric methods of technical diagnostics incorporated into predictive maintenance, which is a part of proactive maintenance. There are methods of vibrodiagnostics, thermography, tribology, borescopy and emissions measurement. Each of these methods has lots of advantages and disadvantages; therefore it is very important to ensure their correct combination for trouble-free operation of those important facilities. Their suitability at work is discussed in the matrix of diagnostic methods application and the PF chart. The output of the work is a proposal of a suitable model of maintenance control which uses multiparametric diagnostic methods for small and big Gas Turbine Engines and optimizes maintenance costs.

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