Primary Surface Recuperator Alloy Oxidation: A Comparison of Accelerated Engine Testing to Field Operation

2010 ◽  
Vol 133 (4) ◽  
Author(s):  
Wendy J. Matthews ◽  
Karren L. More ◽  
Larry R. Walker
Keyword(s):  
Steady State ◽  
Oxide Scale ◽  
National Laboratory ◽  
Normal Operation ◽  
Protective Oxide ◽  
Oak Ridge ◽  
Alloy Oxidation ◽  
Test Engine ◽  
Engine Testing

The Capstone C65 Microturbine primary surface recuperator (PSR) core has been manufactured from Haynes alloy HR-120 since 2005 (Microturbine is a registered trademark of Capstone Turbine Corporation; Haynes and HR-120 are trademarks of Haynes International, Inc.). When exposed to the harsh operating environment of the microturbine PSR, HR-120 forms a protective oxide scale that is resistant to the effects of the water vapor present in the exhaust gas. Long-term accelerated microturbine testing with samples in a modified PSR with a removable aft dome is ongoing at an elevated turbine exit temperature (TET) ∼100°F higher than normal operation. The elevated TET test engine is operated at steady-state conditions, and the engine is shut down at predetermined intervals for sample removal. Material characterization of the elevated TET samples has been carried out by Capstone Turbine Corporation in collaboration with Oak Ridge National Laboratory. The surface oxide scale formation and associated alloy compositional changes have been evaluated for elevated TET samples with operating lives ranging from ∼1800 h to ∼26,500 h. In addition, field-operated HR-120 recuperators have been sectioned and samples have been evaluated for operating lives ranging from ∼5500 h to ∼18,000 h. Results from the microstructural and compositional analyses of both the long-term steady-state elevated TET HR-120 samples and the field-operated HR-120 recuperator samples will be presented and compared.

Primary Surface Recuperator Alloy Oxidation: A Comparison of Accelerated Engine Testing to Field Operation

2010 ◽  
Author(s):  
Wendy J. Matthews ◽  
Karren L. More ◽  
Larry R. Walker
Keyword(s):  
Steady State ◽  
Oxide Scale ◽  
National Laboratory ◽  
Normal Operation ◽  
Protective Oxide ◽  
Oak Ridge ◽  
Alloy Oxidation ◽  
Test Engine ◽  
Engine Testing

The Capstone C65 MicroTurbine Primary Surface Recuperator (PSR) core has been manufactured from Haynes alloy HR-120 since 2005. When exposed to the harsh operating environment of the microturbine PSR, HR-120 forms a protective oxide scale that is resistant to the effects of the water vapor present in the exhaust gas. Long-term accelerated microturbine testing, with samples in a modified PSR with a removable aft dome, is on-going at an elevated Turbine Exit Temperature (TET) ∼100°F higher than normal operation. The elevated TET test engine is operated at steady state conditions and the engine is shut down at pre-determined intervals for sample removal. Material characterization of the elevated TET samples has been carried out by Capstone Turbine Corporation in collaboration with Oak Ridge National Laboratory. The surface oxide scale formation and associated alloy compositional changes have been evaluated for elevated TET samples with operating lives ranging from ∼1,800 – ∼26,500 hours. In addition, field operated HR-120 recuperators have been sectioned and samples have been evaluated for operating lives ranging from ∼5,500 – ∼18,000 hours. Results from the microstructural and compositional analyses of both the long-term steady-state elevated TET HR-120 samples, and the field operated HR-120 recuperator samples, will be presented and compared.

Long-Term Microturbine Exposure of an Advanced Alloy for Microturbine Primary Surface Recuperators

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Wendy J. Matthews ◽  
Karren L. More ◽  
Larry R. Walker
Keyword(s):  
Steady State ◽  
National Laboratory ◽  
Operating Conditions ◽  
Normal Operation ◽  
Operating Environment ◽  
Protective Oxide ◽  
Oak Ridge ◽  
Steady State Operation ◽  
Alloy Oxidation

Haynes alloy HR-120 (Haynes and HR-120 are trademarks of Haynes International, Inc.) forms a protective oxide scale when exposed to the harsh operating environment of a microturbine primary surface recuperator. Primary surface recuperators manufactured from HR-120 are currently in use on the Capstone C65 MicroTurbine (MicroTurbine is a registered trademark of Capstone Turbine Corporation). Long-term microturbine tests of this alloy are currently being conducted at an elevated turbine exit temperature (∼100°F higher than that in a normal operation) at Capstone Turbine Corporation. Alloy samples that have been tested under steady-state microturbine operating conditions are removed after predetermined exposure intervals for characterization by Capstone Turbine Corporation in collaboration with Oak Ridge National Laboratory. Such evaluations include the characterization of surface oxide scales and the associated alloy compositional changes following a steady-state operation ranging from 1800 h to 14,500 h. Results from the microstructural and compositional analyses of these long-term steady-state engine-tested HR-120 samples are used to illustrate the progression of alloy oxidation in the microturbine operating environment.

Long-Term Microturbine Exposure of an Advanced Alloy for Microturbine Primary Surface Recuperators

2008 ◽  
Author(s):  
Wendy J. Matthews ◽  
Karren L. More ◽  
Larry R. Walker
Keyword(s):  
Steady State ◽  
National Laboratory ◽  
Operating Conditions ◽  
Normal Operation ◽  
Operating Environment ◽  
Protective Oxide ◽  
Oak Ridge ◽  
Steady State Operation ◽  
Alloy Oxidation

Haynes Alloy HR-120 forms a protective oxide scale when exposed to the harsh operating environment of a microturbine primary surface recuperator. Primary surface recuperators manufactured from HR-120 are currently in use on the Capstone C65 MicroTurbine. Long-term microturbine tests of this alloy are currently being conducted at an elevated turbine exit temperature (∼100F° higher than normal operation) at Capstone Turbine Corporation. Alloy samples that have been tested under steady-state microturbine operating conditions are removed after pre-determined exposure intervals for characterization by Capstone Turbine Corporation in collaboration with Oak Ridge National Laboratory. Such evaluations include characterization of surface oxide scales and the associated alloy compositional changes following steady-state operation ranging from 1,800 – 14,500 hours. Results from the microstructural and compositional analyses of these long-term, steady-state engine-tested HR-120 samples are used to illustrate the progression of alloy oxidation in the microturbine operating environment.

Engine Testing of an Advanced Alloy for Microturbine Primary Surface Recuperators

2005 ◽  
Author(s):  
Wendy J. Matthews ◽  
Terry Bartel ◽  
Dwaine L. Klarstrom ◽  
Larry R. Walker
Keyword(s):  
Steady State ◽  
Oxide Scale ◽  
Engine Test ◽  
Test Results ◽  
Protective Oxide ◽  
Protective Oxide Scale ◽  
Cyclic Operation ◽  
Engine Testing

HAYNES® alloy HR-120® has been identified as a potential alloy for the manufacture of primary surface recuperators. Primary surface recuperator components have been manufactured from HR-120, and actual microturbine testing is on going. Initial engine test results indicate the formation of a protective oxide scale that is resistant to both steady-state and cyclic operation with no evidence of accelerated attack, and which is likely to meet or exceed the desired 80,000 hour component life.

Sensitivity Study of the South Texas Project Power Plant Steady-State Simulations Using RELAP5-3D Coupled With Dakota

2012 ◽  
Author(s):  
O. A. Rodriguez ◽  
R. Vaghetto ◽  
Y. A. Hassan
Keyword(s):  
Steady State ◽  
Power Plant ◽  
Uncertainty Quantification ◽  
National Laboratory ◽  
Sandia National Laboratory ◽  
Sensitivity Study ◽  
South Texas ◽  
Normal Operation ◽  
Inlet Temperature ◽  
The South

A RELAP5-3D input deck of the South Texas Project (STP) power plant was created in order to study the thermal-hydraulic behavior of the plant during normal operation (steady-state) and during a Loss of Coolant Accident (LOCA). It is important to study the sensitivity of selected output parameters such as the total coolant mass flow rate, the peak clad temperature, the secondary pressure, as a function of specific input parameters (reactor nominal power, vessel inlet temperature, steam generators primary side heat transfer coefficient, primary pressure etc.) in order to identify the variables that play a role in the uncertainty of the thermal-hydraulic calculations. RELAP5-3D, one of the most used best estimate thermal-hydraulic system codes, was coupled with DAKOTA, developed by Sandia National Laboratory for Uncertainty Quantification and Sensitivity Analysis in order to simplify the simulation process and the analysis of the results. In the present paper, the results of the sensitivity study for selected output parameters of the steady-state simulations are presented. The coupled software was validated by repeating one set of simulations using the RELAP5-3D standalone version and by analyzing the simulation results with respect of the physical expectations and behavior of the power plant. The thermal-hydraulic parameters of interest for future uncertainty quantification calculations were identified.

scholarly journals New Retinas for Old

2003 ◽  
Vol 125 (10) ◽  
pp. 42-46 ◽  
Author(s):  
Gayle Ehrenman
Keyword(s):  
Private Sector ◽  
Human Body ◽  
Microelectrode Array ◽  
National Laboratory ◽  
Retinal Prosthesis ◽  
Artificial Retina ◽  
Oak Ridge ◽  
Retinal Tissue ◽  
The Brain

This article reviews retinal prosthesis that is a seeing-eye chip with as many as 1000 tiny electrodes to be implanted in the eye. It has the potential to help people who have lost their sight regain enough vision to function independently in the sighted world. The Artificial Retina Project is a collaboration of five US National laboratories, three universities, and the private sector. The interface module and the antenna for future versions of the retinal prosthesis will all be implanted in the eye, instead of outside the eye. The retinal prosthesis will help patients who still have neutral wiring from the eye to the brain. One of the challenges in developing the device is creating a microelectrode array that conforms to the curved shape of the retina, without damaging the delicate retinal tissue. Oak Ridge National Laboratory in Oak Ridge, Tennessee, is the lead lab on the Artificial Retina Project. They're the folks responsible for fabricating and testing the electrodes, and making sure they're up to the challenge of being implanted long term in a human body.

scholarly journals Improving Nuclear Power Plant Safety with FeCrAl Alloy Fuel Cladding

MRS Advances ◽  
2017 ◽  
Vol 2 (21-22) ◽  
pp. 1217-1224 ◽  
Author(s):  
Raul B. Rebak ◽  
Kurt A. Terrani ◽  
William P. Gassmann ◽  
John B. Williams ◽  
Kevin L. Ledford
Keyword(s):  
Nuclear Power ◽  
National Laboratory ◽  
Alloy System ◽  
Department Of Energy ◽  
Normal Operation ◽  
Oak Ridge ◽  
Plant Safety ◽  
Operation Conditions ◽  
Fecral Alloy ◽  
Nuclear Power Plant Safety

ABSTRACTThe US Department of Energy (DOE) is partnering with fuel vendors to develop enhanced accident tolerant nuclear fuels for Generation III water cooled reactors. In comparison with the standard current uranium dioxide and zirconium alloy system UO2-Zr), the proposed alternative accident tolerant fuel (ATF) should better tolerate loss of cooling in the core for a considerably longer time while maintaining or improving the fuel performance during normal operation conditions. General Electric, Oak Ridge National Laboratory and their partners have proposed to replace zirconium based alloy cladding in current commercial power reactors with an iron-chromium-aluminum (FeCrAl) alloy cladding such as APMT. The use of FeCrAl alloys will greatly reduce the risk of operating the power reactors to produce electricity.

Ceramic Gas Turbine Materials Impact Evaluation

2002 ◽  
Author(s):  
Mark van Roode ◽  
Oscar Jimenez ◽  
John McClain ◽  
Jeff Price ◽  
Vijay Parthasarathy ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Impact Damage ◽  
National Laboratory ◽  
Impact Resistance ◽  
Department Of Energy ◽  
Threshold Velocity ◽  
Oak Ridge ◽  
Engine Testing ◽  
The Impact

Impact of foreign or domestic material on components in the hot section of gas turbines with ceramic components is a common cause of catastrophic failure. Several such occurrences were observed during engine testing under the Ceramic Stationary Gas Turbine program sponsored by the U.S. Department of Energy. A limited analysis was carried out at Solar Turbines Incorporated (Solar), which involved modeling of the impact in the hot section. Based on the results of this study an experimental investigation was carried out at the University of Dayton Research Institute Impact Physics Laboratory to establish the conditions leading to significant impact damage in silicon-based ceramics. The experimental set up involved impacting ceramic flexure bars with spherical metal particulates under conditions of elevated temperature and controlled velocity. The results of the study showed a better correlation of impact damage with momentum than with kinetic energy. Increased test specimen mass and fracture toughness were found to improve impact resistance. Continuous fiber-reinforced ceramic composite (CFCC) materials have better impact resistance than monolithics. A threshold velocity was established for impacting particles of a defined mass. Post-impact metallography was carried out at Oak Ridge National Laboratory to further establish the impact mechanism.

Oxidation Behavior of Prospective Silicon Nitride Materials for Advanced Microturbine Applications

2001 ◽  
Author(s):  
Bjoern Schenk ◽  
Tom Strangman ◽  
Elizabeth J. Opila ◽  
R. Craig Robinson ◽  
Dennis S. Fox ◽  
...  
Keyword(s):  
Silicon Nitride ◽  
Elevated Temperatures ◽  
National Laboratory ◽  
Test Facility ◽  
Environmental Barrier ◽  
Oak Ridge ◽  
Oxidation Test ◽  
Environmental Barrier Coating ◽  
Barrier Coating ◽  
Engine Testing

Various laboratory tests have shown that high-pressure water vapor environments combined with elevated temperatures and intermediate gas velocities (current facilities limited to about 50 m/s) can cause grain boundary degradation and material recession in silica formers. Recent tests include burner rig testing conducted by NASA [1], Honeywell Engines & Systems [2], Siemens Power Generation [3], CRIEPI in Japan [4, 5], “Keiser rig” testing at Oak Ridge National Laboratory (ORNL) [6], and engine testing in the Allison 501K industrial gas turbine [7]. This paper presents a summary of oxidation test data of candidate silicon nitride materials for advanced microturbine applications. These data are of interest to microturbine component designers in order to determine the limits of safe unprotected component operation with respect to the given turbine environment, as well as to understand the behavior of ceramic microturbine components once local spallation of the protective environmental barrier coating has occurred. This paper intends to give materials and engine development engineers some guidance with respect to the different test facility capabilities and the prevailing oxidation/recession mechanisms to better understand/interprete the oxidation test results when developing new ceramic material compositions and environmental barrier coating systems.

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