Computer-Assisted Manufacturing of a Low Thermal Stress Gasturbine Inner Casing

1991 ◽  
Author(s):  
Jürgen Brinkmann ◽  
Peter Dietrich
Keyword(s):  
Gas Turbine ◽  
Design Principle ◽  
Computer Assisted ◽  
Quality Requirements ◽  
Impingement Cooling ◽  
Hot Gas ◽  
Cad Cam ◽  
Manufacturing Techniques ◽  
Important Design ◽  
Double Wall

This technical paper describes the computer-assisted manufacturing of a newly developed gas turbine inner casing designed by Siemens/KWU for hot gas temperatures up to 1350 °C. After explaining the most important design features, double wall casing with intensive impingement cooling, and details on the special materials involved, the manufacturing sequence and requisite special manufacturing techniques are described. The significant advantages and benefits of a CAD/CAM system tailored to the respective technique employed for this key aerodynamically-optimized item of a stationary gas turbine are elucidated in light of economic concerns and quality requirements and conditions imposed. In conclusion, the transferability of the design principle described in this paper and its implementation in future-oriented developments in fabrication techniques employed in the manufacture of hot-gas-path casings at even higher temperatures are discussed.

Alstom Post-Development of GT24 and GT26 Hot Gas Turbine Parts Reconditioning

2009 ◽  
Author(s):  
N. Schro¨der ◽  
G. Drensky ◽  
S. Florjancic
Keyword(s):  
Gas Turbine ◽  
New Technologies ◽  
Throughput Time ◽  
Performance Impact ◽  
Hot Gas ◽  
Performance Requirements ◽  
Repair Costs ◽  
Performance Statistics ◽  
Manufacturing Techniques ◽  
And Performance

Reconditioning of hot gas turbine parts is driven mainly by lifetime and performance requirements. Commonly, the first approach in reconditioning is to achieve an exact reproduction of a new manufactured part, by following new part specifications. However, this may prove to be too costly and unnecessary. The unique OEM experience, allows ALSTOM to widen these specifications in order to optimize repair costs, improve throughput time and possibly reduce parts scrap rate without sacrificing lifetime and performance. This post-development is based on MI calculations re-calibrated and reinsured by extensive empirical field feedback and performance statistics over the whole GT fleet with millions of operating hours. This paper presents an overview of the required area of the OEM’s expertise and field data within post development, substantiated by examples from daily operations. The work is performed in order to ensure safe remaining part lifetime along with full functionality and known performance impact. Parameters influencing the remaining part lifetime are micro-structural degradation, crack allowances, coating properties and minimum wall thicknesses, while, parameters influencing performance are airflow specifications, radial clearances, sealing design and surface roughness. Furthermore, different manufacturing techniques and new technologies get investigated and then implemented whenever there is an opportunity to optimize process cost effectiveness and reach higher quality standards. This is done in order to ensure that the company retains its competitive edge over other reconditioning companies. As the complexity of components varies, the unique knowledge of each component allows ALSTOM to develop the most favorable reconditioning processes. This enables state-of-the-art reconditioning and repair methods to be utilized. Thus ensuring optimum throughput time, while minimizing scrap rates and maintaining performance and lifetime requirements. This unique experience and knowledge from the reconditioning processes is transferred as a benefit to the customer and also utilized in future designs, resulting in improved new part designs and optimized life cycle costs.

scholarly journals Advances in 3D Printing for Tissue Engineering

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3149
Author(s):  
Angelika Zaszczyńska ◽  
Maryla Moczulska-Heljak ◽  
Arkadiusz Gradys ◽  
Paweł Sajkiewicz
Keyword(s):  
Tissue Engineering ◽  
Additive Manufacturing ◽  
3D Printing ◽  
Complex Structure ◽  
Three Dimensional ◽  
Computer Assisted ◽  
Scaffold Fabrication ◽  
Manufacturing Techniques ◽  
Printing Techniques ◽  
State Of Art

Tissue engineering (TE) scaffolds have enormous significance for the possibility of regeneration of complex tissue structures or even whole organs. Three-dimensional (3D) printing techniques allow fabricating TE scaffolds, having an extremely complex structure, in a repeatable and precise manner. Moreover, they enable the easy application of computer-assisted methods to TE scaffold design. The latest additive manufacturing techniques open up opportunities not otherwise available. This study aimed to summarize the state-of-art field of 3D printing techniques in applications for tissue engineering with a focus on the latest advancements. The following topics are discussed: systematics of the available 3D printing techniques applied for TE scaffold fabrication; overview of 3D printable biomaterials and advancements in 3D-printing-assisted tissue engineering.

Effects of Thermal Exposure on Microstructure and Mechanical Properties of Ni Based Superalloy GTD111

2011 ◽  
Vol 275 ◽  
pp. 31-34 ◽  
Author(s):  
Han Sang Lee ◽  
Keun Bong Yoo ◽  
Doo Soo Kim ◽  
Jae Hoon Kim
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Operating Temperature ◽  
Rupture Strength ◽  
Mechanical Test ◽  
Thermal Exposure ◽  
Creep Rupture Strength ◽  
Material Degradation ◽  
Temperature Dependent ◽  
Hot Gas

The rotating components in the hot sections of land-based gas turbine are exposed to severe environment during several ten thousand hours at above 1100 oC operating temperature. The failure mechanism of the hot gas components would be accompanied by material degradation in the properties of high temperature and creep rupture strength. Many hot gas components in gas turbine are made of Ni-based superalloy because of their high temperature performance. In this work, we surveyed the time and temperature dependent degradation of Ni-based superalloy. We prepared the specimens from GTD111 that are exposed at 871 oC and 982 oC in 1,000 ~ 10,000 hours. We carried out the mechanical test and microstructural observation.

Build Direction Effects on Additively Manufactured Channels

2015 ◽  
Author(s):  
Jacob C. Snyder ◽  
Curtis K. Stimpson ◽  
Karen A. Thole ◽  
Dominic Mongillo
Keyword(s):  
Heat Transfer ◽  
Gas Turbine ◽  
Pressure Loss ◽  
Small Scale ◽  
Turbine Cooling ◽  
Gas Turbine Cooling ◽  
Gas Turbine Heat Transfer ◽  
Manufacturing Techniques ◽  
Traditional Manufacturing

With the advances of Direct Metal Laser Sintering (DMLS), also generically referred to as additive manufacturing, novel geometric features of internal channels for gas turbine cooling can be achieved beyond those features using traditional manufacturing techniques. There are many variables, however, in the DMLS process that affect the final quality of the part. Of most interest to gas turbine heat transfer designers are the roughness levels and tolerance levels that can be held for the internal channels. This study investigates the effect of DMLS build direction and channel shape on the pressure loss and heat transfer measurements of small scale channels. Results indicate that differences in pressure loss occur between the test cases with differing channel shapes and build directions, while little change is measured in heat transfer performance.

Effects of Effusion Cooling Pattern Near the Dilution Hole for a Double-Walled Combustor Liner: Part 2 — Flowfield Measurements

2018 ◽  
Author(s):  
Adam C. Shrager ◽  
Karen A. Thole ◽  
Dominic Mongillo
Keyword(s):  
Leading Edge ◽  
Freestream Turbulence ◽  
Gas Turbine Combustor ◽  
Impingement Cooling ◽  
Cooling Pattern ◽  
Image Velocimetry ◽  
Cooling Hole ◽  
Difficult Challenge ◽  
Combustor Liner ◽  
Double Wall

The complex flowfield inside a gas turbine combustor creates a difficult challenge in cooling the combustor walls. Many modern combustors are designed with a double-wall that contain both impingement cooling on the backside of the wall and effusion cooling on the external side of the wall. Complicating matters is the fact that these double-walls also contain large dilution holes whereby the cooling film from the effusion holes is interrupted by the high-momentum dilution jets. Given the importance of cooling the entire panel, including the metal surrounding the dilution holes, the focus of this paper is understanding the flow in the region near the dilution holes. Near-wall flowfield measurements are presented for three different effusion cooling hole patterns near the dilution hole. The effusion cooling hole patterns were varied in the region near the dilution hole and include: no effusion holes; effusion holes pointed radially outward from the dilution hole; and effusion holes pointed radially inward toward the dilution hole. Particle image velocimetry (PIV) was used to capture the time-averaged flowfield at approaching freestream turbulence intensities of 0.5% and 13%. Results showed evidence of downward motion at the leading edge of the dilution hole for all three effusion hole patterns. In comparing the three geometries, the outward effusion holes showed significantly higher velocities toward the leading edge of the dilution jet relative to the other two geometries. Although the flowfield generated by the dilution jet dominated the flow downstream, each cooling hole pattern interacted with the flowfield uniquely. Approaching freestream turbulence did not have a significant effect on the flowfield.

Numerical Investigation of Improving Turbine Sealing Effectiveness Through Slot Width Modification of the Rim Seal

2013 ◽  
Author(s):  
Jinghui Zhang ◽  
Hongwei Ma
Keyword(s):  
Radial Velocity ◽  
Gas Turbine ◽  
Flow Region ◽  
Main Flow ◽  
Slot Width ◽  
Wake Region ◽  
Reference Case ◽  
Cooling Flow ◽  
Hot Gas ◽  
Root Region

The hot gas in the main annulus of a gas turbine can ingest into the rotor-stator cavities through the rim seal clearance as a result of the interaction of the rotor and the stator disks and the external flow in the hot gas annulus. To prevent the turbine root region from being heated up, this ingestion has to be avoided almost completely. This paper introduces a new idea to improve turbine sealing effectiveness through slot width modification of the rim seal. Unsteady numerical simulations are performed with two different rim seal geometries at the design condition with different cooling flow rates. Both of the rim seal geometries are simple axial seal configurations. One is uniform slot rim seal geometry and is taken as the reference case. The other is a new kind of rim seal geometry with slot width modification. The clearance is bigger in the main flow path and smaller in the stator wake region keeping the area of the two kinds of rim seal surfaces equivalent. The sealing air egress happens in the main path flow region and the ingestion happens in the stator wake region. Through comparing the results of the two kinds of rim seal geometries, it is found out that the contoured slot rim seal geometry can reduce the pressure in the cavity which leads to the decrease of the gas turbine loss. The inward radial velocity of the ingestion increases in the stator wake region and hence the axial seal gap has been reduced in this region. The time-averaged outward radial velocity decreases in the main flow region and becomes more uniform. Unsteady flow patterns in the rim seal region are compared for the two seal configurations. The sealing effectiveness is rapidly improved by using the contoured seal configuration. This work provides an idea to increase the sealing effectiveness and decrease the pressure in the cavity.

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