Static Testing of Compliant Plate Seals

2012 ◽  
Author(s):  
Hrishikesh V. Deo ◽  
Deepak Trivedi
Keyword(s):  
Gas Turbines ◽  
High Speed ◽  
Pressure Ratio ◽  
Differential Pressure ◽  
Tip Clearance ◽  
Design Parameters ◽  
Outer Diameter ◽  
Steam Turbines ◽  
Low Leakage ◽  
The Impact

Self–correcting Compliant Plate Seals are being developed for various turbomachinery sealing applications including gas turbines, steam turbines, aircraft engines and oil & gas compressors. These seals consist of compliant plates attached to a stator in a circumferential fashion around the rotor. The compliant plates have a slot that extends radially inwards from the seal outer diameter, and an intermediate plate extends inwards into this slot from stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip–clearance. Due to this self–correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and robust non–contact operation even in the presence of large rotor transients. In this paper we have described the testing of Compliant Plate Seals in a static leakage test rig (“shoebox” rig) to study the impact of different design parameters on leakage and vibration. A novel high–speed visualization set–up is described and the high–speed videos demonstrate robust non–contact operation for different assembly clearances, bridge–gaps and bridge–heights, for various differential pressure and pressure ratio conditions. The reported leakage results indicate that the leakage is relatively insensitive to assembly clearances due to the self–correcting behavior.

Compliant Plate Seals: Design and Performance Simulations

2012 ◽  
Author(s):  
Hrishikesh V. Deo ◽  
Ajay Rao ◽  
Hemant Gedam
Keyword(s):  
Gas Turbines ◽  
Tip Clearance ◽  
Outer Diameter ◽  
Aircraft Engines ◽  
Steam Turbines ◽  
Flow Rates ◽  
Cfd Models ◽  
Low Leakage ◽  
And Performance ◽  
Large Rotor

Compliant Plate Seals are being developed for various turbomachinery sealing applications including gas turbines, steam turbines, aircraft engines and oil & gas compressors. These seals consist of compliant plates attached to a stator in a circumferential fashion around a rotor. The compliant plates have a slot that extends radially inwards from the seal outer diameter, and an intermediate plate extends inwards into this slot from stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip–clearance. Due to this self–correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and non–contact operation even in the presence of large rotor transients. CFD models have been developed to predict the leakage flow rates and hydrostatic lift and blowdown forces, and a design philosophy is proposed to predict the feedback phenomenon from the CFD results.

Side Weld and Bend Method of Manufacturing Compliant Plate Seals

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
William E. Adis ◽  
Michael Mack ◽  
Hrishikesh V. Deo
Keyword(s):  
Gas Turbines ◽  
Oil And Gas ◽  
Tip Clearance ◽  
Outer Diameter ◽  
Steam Turbines ◽  
Manufacturing Method ◽  
Low Leakage ◽  
Straight Line ◽  
Differential Shrinkage ◽  
Large Rotor

Compliant plate seals are being developed for various turbomachinery sealing applications including gas turbines, steam turbines, aircraft engines, and oil and gas compressors. These seals consist of compliant plates attached to a stator in a circumferential fashion around a rotor. The compliant plates have a slot that extends radially inward from the seal outer diameter and an intermediate plate extends inward into this slot from the stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip clearance. Due to this self-correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and robust noncontact operation even in the presence of large rotor transients. Manufacturing of compliant plate seals is a challenging problem and in this paper we describe the development of a novel manufacturing technique called side weld and bend (SWAB). The compliant plates are tightly packed with alternating spacer shims in a straight line fixture and welded to a top plate from the side along a straight line. After removal of the spacer shims, the welded assembly is bent to form an arcuate seal of a desired diameter. The side weld and bend (SWAB) manufacturing method reduces distortion, deformity, differential shrinkage, and other associated problems with welding across gaps between adjacent compliant plate seals as is typical in current manufacturing processes.

Compliant Plate Seals: Testing and Validation

2012 ◽  
Author(s):  
Hrishikesh V. Deo
Keyword(s):  
High Frequency ◽  
Gas Turbines ◽  
Tip Clearance ◽  
Outer Diameter ◽  
Aircraft Engines ◽  
Test Results ◽  
Steam Turbines ◽  
Leakage Test ◽  
Low Leakage ◽  
Large Rotor

Compliant Plate Seals are being developed for various turbomachinery sealing applications including gas turbines, steam turbines, aircraft engines and oil & gas compressors. These seals consist of compliant plates attached to a stator in a circumferential fashion around the rotor. The compliant plates have a slot that extends radially inwards from the seal outer diameter, and an intermediate plate extends inwards into this slot from stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip–clearance. Due to this self–correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and non-contact operation even in the presence of large rotor transients. In this paper, we have reported leakage test results for Compliant Plate Seals and visually demonstrated robust non-contact operation for different assembly clearances and interferences, stator deflections, high frequency rotor transients, different pressure conditions and rotational speeds.

Side Weld and Bend Method of Manufacturing Compliant Plate Seals

2013 ◽  
Author(s):  
William E. Adis ◽  
Michael Mack ◽  
Hrishikesh V. Deo
Keyword(s):  
Gas Turbines ◽  
Tip Clearance ◽  
Outer Diameter ◽  
Aircraft Engines ◽  
Steam Turbines ◽  
Manufacturing Method ◽  
Low Leakage ◽  
Straight Line ◽  
Differential Shrinkage ◽  
Large Rotor

Compliant Plate Seals are being developed for various turbomachinery sealing applications including gas turbines, steam turbines, aircraft engines and oil & gas compressors. These seals consist of compliant plates attached to a stator in a circumferential fashion around a rotor. The compliant plates have a slot that extends radially inwards from the seal outer diameter and an intermediate plate extends inwards into this slot from the stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip-clearance. Due to this self-correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and robust non-contact operation even in the presence of large rotor transients. Manufacturing of Compliant Plate Seals is a challenging problem and in this paper, we describe the development of a novel manufacturing technique called Side Weld And Bend (SWAB). The compliant plates are tightly packed with alternating spacer shims in a straight line fixture and welded to a top-plate from the side along a straight line. After removal of the spacer shims, the welded assembly is bent to form an arcuate seal of a desired diameter. The Side Weld And Bend (SWAB) manufacturing method reduces distortion, deformity, differential shrinkage and other associated problems with welding across gaps between adjacent compliant plate seals as is typical in current manufacturing processes.

The Fouling of Axial Flow Compressors: Causes, Effects, Susceptibility, and Sensitivity

2009 ◽  
Author(s):  
Cyrus B. Meher-Homji ◽  
Mustapha Chaker ◽  
Andrew F. Bromley
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Simulation Analysis ◽  
Pressure Ratio ◽  
Axial Flow ◽  
Design Parameters ◽  
Comprehensive Treatment ◽  
Performance Deterioration ◽  
And Control ◽  
The Impact

Increased fuel costs have created a strong incentive for gas turbine operators to understand, minimize and control performance deterioration. The most prevalent deterioration problem faced by gas turbine operators is compressor fouling. Fouling causes a drop in airflow, pressure ratio and compressor efficiency, resulting in a “re-matching” of the gas turbine and compressor and a drop in power output and thermal efficiency. This paper addresses the causes and effects of fouling and provides a comprehensive treatment of the impact of salient gas turbine design parameters on the susceptibility and sensitivity to compressor fouling. Simulation analysis of ninety two (92) gas turbines of ranging from a few kW to large engines rated at greater than 300 MW has been conducted. It is hoped that this paper will provide practical information to gas turbine operators.

Compliant Plate Seals for Turbomachinery Applications

2011 ◽  
Author(s):  
Hrishikesh V. Deo
Keyword(s):  
Experimental Testing ◽  
Differential Pressure ◽  
Tip Clearance ◽  
Outer Diameter ◽  
Leakage Flow ◽  
Blow Down ◽  
Flow Rates ◽  
Cfd Models ◽  
Low Leakage ◽  
Large Rotor

In this paper, a novel GE Compliant Plate Seal is proposed that consists of compliant plates attached to a stator in a circumferential fashion around a rotor. The compliant plates have a slot that extends radially inwards from the seal outer diameter, and an intermediate plate extends inwards into this slot from stator. This design is capable of providing passive hydrostatic feedback forces acting on the compliant plates that balance at a small tip-clearance. When the tip-clearance reduces below the equilibrium clearance, the hydrostatic lift forces cause the compliant plates to lift away from the rotor. Conversely when the tip-clearance increases above the equilibrium clearance, the hydrostatic blowdown forces cause the compliant plates to blow down towards the rotor. Due to this self-correcting behavior, this seal is capable of providing high differential pressure capability and low leakage within a limited axial span, and non-contact operation even in the presence of large rotor transients. Simplified CFD models have been developed to predict the leakage flow rates and hydrostatic lift and blowdown forces, and a design philosophy is proposed to predict the feedback phenomenon from the CFD models. The proposed models are validated and self-correcting behavior is demonstrated through experimental testing.

Impact of Operating Conditions and Design Parameters on Gas Turbine Hot Section Creep Life

2010 ◽  
Author(s):  
S. Eshati ◽  
M. F. Abdul Ghafir ◽  
P. Laskaridis ◽  
Y. G. Li
Keyword(s):  
Gas Turbines ◽  
Performance Model ◽  
Operating Conditions ◽  
Creep Model ◽  
Design Parameters ◽  
Gas Temperature ◽  
Creep Life ◽  
Cooling Effectiveness ◽  
Radial Temperature ◽  
The Impact

This paper investigates the relationship between design parameters and creep life consumption of stationary gas turbines using a physics based life model. A representative thermodynamic performance model is used to simulate engine performance. The output from the performance model is used as an input to the physics based model. The model consists of blade sizing model which sizes the HPT blade using the constant nozzle method, mechanical stress model which performs the stress analysis, thermal model which performs thermal analysis by considering the radial distribution of gas temperature, and creep model which using the Larson-miller parameter to calculate the lowest blade creep life. The effect of different parameters including radial temperature distortion factor (RTDF), material properties, cooling effectiveness and turbine entry temperatures (TET) is investigated. The results show that different design parameter combined with a change in operating conditions can significantly affect the creep life of the HPT blade and the location along the span of the blade where the failure could occur. Using lower RTDF the lowest creep life is located at the lower section of the span, whereas at higher RTDF the lowest creep life is located at the upper side of the span. It also shows that at different cooling effectiveness and TET for both materials the lowest blade creep life is located between the mid and the tip of the span. The physics based model was found to be simple and useful tool to investigate the impact of the above parameters on creep life.

An Optimization Design Platform for Fir-Tree Root and Groove for Steam Turbine

2018 ◽  
Author(s):  
Deqi Yu ◽  
Xiaojun Zhang ◽  
Jiandao Yang ◽  
Kai Cheng ◽  
Weilin Shu ◽  
...  
Keyword(s):  
Stress Concentration ◽  
Steam Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Optimization Design ◽  
Turbine Blades ◽  
Local Stress ◽  
Optimization Method ◽  
Steam Turbines ◽  
Geometry Configuration

Fir-tree root and groove profiles are widely used in gas turbine and steam turbine. Normally, the fir-tree root and groove are characterized with straight line, arc or even elliptic fillet and splines, then the parameters of these features were defined as design variables to perform root profile optimization. In ultra-long blades of CCPP and nuclear steam turbines and high-speed blades of industrial steam turbine blades, both the root and groove strength are the key challenges during the design process. Especially, in industrial steam turbines, the geometry of blade is very small but the operation velocity is very high and the blade suffers stress concentration severely. In this paper, two methods for geometry configuration and relevant optimization programs are described. The first one is feature-based using straight lines and arcs to configure the fir-tree root and groove geometry and genetic algorithm for optimization. This method is quite fit for wholly new root and groove design. And the second local optimization method is based on B-splines to configure the geometry where the local stress concentration occurs and the relevant optimization algorithm is used for optimization. Also, several cases are studied as comparison by using the optimization design platform. It can be used not only in steam turbines but also in gas turbines.

Direct Outer Ring Cooling of a High Speed Jet Engine Mainshaft Ball Bearing: Experimental Investigation Results

2010 ◽  
Author(s):  
Peter Gloeckner ◽  
Klaus Dullenkopf ◽  
Michael Flouros
Keyword(s):  
Power Dissipation ◽  
High Speed ◽  
Ball Bearing ◽  
Operating Conditions ◽  
Outer Ring ◽  
Outer Diameter ◽  
Propulsion Systems ◽  
Jet Engine ◽  
Power Loss Reduction ◽  
The Impact

Operating conditions in high speed mainshaft ball bearings applied in new aircraft propulsion systems require enhanced bearing designs and materials. Rotational speeds, loads, demands on higher thrust capability, and reliability have increased continuously over the last years. A consequence of these increasing operating conditions are increased bearing temperatures. A state of the art jet engine high speed ball bearing has been modified with an oil channel in the outer diameter of the bearing. This oil channel provides direct cooling of the outer ring. Rig testing under typical flight conditions has been performed to investigate the cooling efficiency of the outer ring oil channel. In this paper the experimental results including bearing temperature distribution, power dissipation, bearing oil pumping and the impact on oil mass and parasitic power loss reduction are presented.

Operational Performance and Locally Resolved Outflow of Brush Seals

2019 ◽  
Author(s):  
Fabian Schur ◽  
Jens Friedrichs
Keyword(s):  
Operational Performance ◽  
Design Parameters ◽  
Steam Turbines ◽  
Test Rig ◽  
Rotating Shaft ◽  
Experimental Conditions ◽  
Widespread Application ◽  
Backing Plate ◽  
Brush Seals ◽  
The Impact

Abstract As a result of the superior leakage efficiency of brush seals compared to conventional labyrinth seals, compliant contacting filament seals are used to increase the efficiency of jet engines as well as stationary gas and steam turbines. The widespread application of brush seals at different and varying pressure differences combined with variable contacting velocities at the rotor surface requires a profound understanding of the influences of different design parameters on the operational leakage performance. In order to systematically investigate the impact of different design parameters on sealing performance, a new cold air test rig was developed. The new test rig with rotating shaft enables hot-wire anemometry measurements downstream of the seals. These measurements provide insight into the locally resolved flow structure in addition to the integral leakage measurements. For the investigations, one welded and five different clamped brush seals at rotational speeds up to 3000rpm and pressure differences across the seals up to 500kPa are considered. Therefore, the influence of two different designs on the flow through the bristles is presented. For the clamped brush seals, variations of the front and backing plate are investigated. Additionally, the effects of bristle diameter and three different axial inclinations of the bristle pack on the sealing efficiency are shown. Furthermore, initial wear development during the first 30 to 60 hours of brush seal operation at varying experimental conditions is presented and linked to the design parameters. Consequently, the effects of major design aspects on the operational performance of brush seals are examined and presented.

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