22 results on '"Chenzhou Lian"'
Search Results
2. Study of Exhaust Gas Reingestion
- Author
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Noopur Joshi, James R. Forsythe, Byung-Young Min, Chenzhou Lian, Brian E. Wake, Jacob Allen, Patrick Bowles, Jonathan Frydman, Shyam Neerarambam, Donald Lamb, Buvana Jayaraman, Noah Becker, Russell W. Powers, and Alexander F. Dunn
- Subjects
Waste management ,Environmental science ,Exhaust gas - Published
- 2021
3. Thermography and Computational Fluid Dynamic Comparisons on the CH-53K King Stallion
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Zachary Stratton, Chris Kennedy, Jonathan Frydman, John T. Spyropoulos, Patrick Bowles, Donald Lamb, Chris Yamamoto, Greg Harrington, Craig Collins, Bjorn Foote, Mike Kazlauskas, Chenzhou Lian, Russell W. Powers, Byung-Young Min, Noah Becker, James R. Forsythe, Shyam Neerarambam, Michael Alexander, Brian E. Wake, and Alexander F. Dunn
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Acoustics ,Thermography ,Environmental science - Published
- 2021
4. Engine Bay Cooling and Model Based Design on the CH-53K King Stallion
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Matthew T. Kube-McDowell, John T. Spyropoulos, Patrick Bowles, Zachary Stratton, Donald Lamb, Chenzhou Lian, Brian E. Wake, Alexander F. Dunn, Greg Harrington, Craig Collins, Jonathan Frydman, Mike Kazlauskas, Shyam Neerarambam, and Russell W. Powers
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Engineering ,Thesaurus (information retrieval) ,Database ,business.industry ,Model-based design ,business ,computer.software_genre ,computer ,Bay - Published
- 2021
5. An Overview of the Exhaust Gas Reingestion Challenges on the CH 53K King Stallion
- Author
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Chenzhou Lian, Zachary Stratton, Greg Harrington, Noah Becker, John T. Spyropoulos, Noopur Joshi, Brian E. Wake, Byung-Young Min, Alexander F. Dunn, James R. Forsythe, Shyam Neerarambam, Chris Foti, Patrick Bowles, Mike Kazlauskas, Russell W. Powers, Jonathan Frydman, Joseph Lawrence Simonetti, Donald Lamb, Jim Axtell, Buvana Jayaraman, and Craig Collins
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Physics ,Waste management ,Exhaust gas - Published
- 2021
6. The CH-53K Exhaust Gas Reingestion Trade Study: Using a Tiered CFD Modeling Approach to Solving the EGR Challenges on the CH-53K King Stallion
- Author
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Byung-Young Min, Jacob Allen, Matthew T. Kube-McDowell, Zachary Stratton, James R. Forsythe, Chenzhou Lian, Greg Harrington, Erica Siegel, Patrick Bowles, Brian E. Wake, John T. Spyropoulos, Donald Lamb, Shyam Neerarambam, Jonathan Frydman, Craig Collins, Alexander F. Dunn, Buvana Jayaraman, and Russell W. Powers
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business.industry ,Exhaust gas ,Environmental science ,Computational fluid dynamics ,Process engineering ,business - Published
- 2021
7. Flight Test Execution and Data Reduction Techniques of Exhaust Gas Reingestion on the CH-53K King Stallion
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Christopher Adams, James Kenna, Alexander F. Dunn, Roger Tull, Noopur Joshi, Shyam Neerarambam, Noah Becker, Mike Kazlauskas, Donald Lamb, Chenzhou Lian, Byung-Young Min, Jonathan Frydman, Patrick Bowles, Brian E. Wake, and Adam Chesser
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Environmental science ,Exhaust gas ,Automotive engineering ,Flight test ,Data reduction - Published
- 2021
8. Effects of Chamber Diameter on the Flowfield in Unielement Rocket Combustors
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Chenzhou Lian, Guoping Xia, and Charles L. Merkle
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business.product_category ,Computer science ,business.industry ,Mechanical Engineering ,Nozzle ,Aerospace Engineering ,Injector ,Propulsion ,law.invention ,Chamber pressure ,Fuel Technology ,Rocket ,Space and Planetary Science ,law ,Combustor ,Rocket engine ,Combustion chamber ,Aerospace engineering ,business - Abstract
U NI-ELEMENT combustors embodying a single fuel oxidizer, injector pair constitute the smallest scale at which combustors can be tested in a rocket engine development program. These unielement systems provide fundamental information on combustor operation that cannot be obtained on larger sized rigs. The small scale provides an economical and safe test bed that allows more detailed instrumentation and much faster turn-around time than that for a practical larger scale combustor. The relatively simple geometry and construction is conducive to the application of advanced diagnostics while also lending itself to detailed computational fluid dynamics (CFD) analyses, both of which can aid in understanding and improving this most fundamental engine building block. Unielement testing is also useful for screening candidate injector types for a new engine, for diagnosing the performance of existing engines, or for fundamental academic studies into high-intensity combustion phenomena. A primary goal of unielement testing in an engine development program is to replicate as closely as possible the environment that a stream tube from an individual element will experience in the fullscale engine. Accordingly, unielement tests must be done with injector elements that are exact scaled copies of those to be used in the full-scale engine, both in terms of kinetic/kinematic and geometrical details. Additionally, the flow rates, oxidizer-to-fuel (O/F) ratios, and incoming propellant temperatures and pressures must match engine conditions, whereas the nozzle must be sized to ensure the proper chamber pressure. Finally, the length of the chamber should be matched to the distance from the injector face to the nozzle throat in the engine to ensure similar characteristic flow times. Clearly, interelement interactions and the intricate recirculation regions adjacent to the face of the full-scale engine cannot be replicated in unielement studies, but unielement combustors are widely used and accepted as an effective means for understanding rocket combustors and as an important precursor to subscale engine studies. A point of continuing controversy in unielement testing, however, concerns the cross-sectional size and shape of the chamber. A key argument has been that the unielement chamber should be sized to provide the cross-sectional area occupied by the stream tube from a single injector element in the full-scale engine, thereby reproducing the proper mean flowMach number. The impact of the cross section on instrumentation and optical diagnostics as well as on CFD modeling is, however, also an important concern that affects shape and size. Experimental configurations with optical access (which enables much more detailed quantitative measurements) drive the chamber cross section to larger sizes. Square chambers, such as those used in early experiments by Moser et al. [1], Foust et al. [2], and De Groot et al. [3], are most convenient for optical diagnostics but potentially introduce geometry-specific corner flows that are not present in engines and are difficult to represent in CFD analyses. Circular chambers eliminate concerns of corner flows and are also friendlier toward CFD modeling, but even with round chambers larger diameters facilitate optical access and advanced diagnostics. Increased chamber diameters, however, give rise to stronger recirculation regions adjacent to the injector face that eventually dominate flame attachment and the ensuing combustion processes. Despite these uncertainties, definitive experiments or computations concerning the effect of chamber Mach number and combustor diameter have never been attempted. The present paper represents a first attempt to address some of these issues. In the past decade, unielement combustors have been studied intensively, both experimentally [1–13] and computationally [14– 22]. The numerous experimental activities have provided detailed insights into, and visualization of, the flowmixing and combustion in unielement combustors. Important relationships between the physical phenomena and operating conditions, such as the momentum ratio and properties of the propellants, the density and velocity ratios of the jets, the temperature and pressure of the combustion chamber, and the role of the detailed local geometry, have been identified. In addition to physical understanding, there has been an emphasis on obtaining detailed experimental data for use in validating CFD models. Presented as Paper 2009-3897 at the 39th AIAA Fluid Dynamics Conference, San Antonio, TX, 22–25 June 2009; received 26 May 2011; revision received 12 December 2011; accepted for publication 14 December 2011. Copyright © 2011 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved. Copies of this paper may be made for personal or internal use, on condition that the copier pay the $10.00 per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923; include the code 0748-4658/12 and $10.00 in correspondence with the CCC. Postdoctoral Research Fellow; currently Staff Scientist, IBM Corporation, Inc., Hudson Valley Research Park, Hopewell Junction, NY 15233; chenzhoulian@gmail.com (Corresponding Author). Reilly Professor of Engineering. Senior Research Associate, School of Mechanical Engineering. JOURNAL OF PROPULSION AND POWER Vol. 28, No. 3, May–June 2012
- Published
- 2012
9. Contrast between steady and time-averaged unsteady combustion simulations
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Chenzhou Lian and Charles L. Merkle
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Materials science ,General Computer Science ,business.industry ,Flow (psychology) ,Diffusion flame ,General Engineering ,Thermodynamics ,Mechanics ,Computational fluid dynamics ,Combustion ,Chamber pressure ,Vortex ,Heat flux ,Combustor ,Combustion chamber ,business ,Reynolds-averaged Navier–Stokes equations - Abstract
Time-averaged predictions from unsteady solutions of the two-dimensional Navier-Stokes equations are contrasted with Reynolds-averaged results for a reacting flow problem in a high pressure combustor. The goal is to determine whether the two-dimensional unsteady approximation can be useful as an engineering analysis in problems for which time-averaged quantities are of primary interest. The conditions are taken from an experiment in which non-premixed gaseous oxygen and hydrogen were injected into a combustion chamber through coaxial channels. The resulting flowfield is dominated by a large recirculation zone arising from the back-step created by the injector. The results of steady and time-averaged, unsteady solutions are strikingly different. The unsteady simulation produces strong unsteady structures whose time-averaged results lead to a much wider flame zone, a different recirculation zone structure, and a substantially different wall heat flux. The time-averaged calculations yield the correct combustor chamber pressure and compare considerably more favorably with heat flux measurements than do the RANS results. The two-dimensional approximation, however, overstates the unsteady vortex roll up and precludes large-scale mixing across the axis of symmetry, thereby giving deficient predictions near the centerline. Overall, the present results indicate that capturing large-scale unsteady characteristics can provide more accurate predictions of recirculation dominated reacting flows and suggest that two-dimensional, time-averaged solutions represent a potentially useful engineering tool for problems of this nature while also serving as a precursor for full three-dimensional simulations.
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- 2011
10. Impact of source terms on reliability of CFD algorithms
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Chenzhou Lian, Guoping Xia, and Charles L. Merkle
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General Computer Science ,business.industry ,Flow (psychology) ,General Engineering ,Stability (learning theory) ,Computational fluid dynamics ,Term (time) ,symbols.namesake ,Dynamic problem ,Jacobian matrix and determinant ,Convergence (routing) ,symbols ,business ,Algorithm ,Reliability (statistics) - Abstract
Source terms often appear in various fluid dynamic problems. These source terms not only have an important impact on the physics of the flow but they can also impact the reliability of CFD algorithms. A general recommendation for differencing negative value sources (sinks) is to treat them implicitly, while positive value sources (sources) should be evaluated explicitly. Although this provides improvements compared with evaluating all terms in the same manner, sources with positive values, in particular, often cause convergence difficulties. The present paper addresses the reasons for these difficulties and combines a new source term evaluation method with time step limitation for convection and diffusion terms to give more robust capability. The method is verified by a combination of stability analysis followed by computational experiments to validate the stability findings in meaningful problems. The source Jacobian arising from a twoequation k-� turbulence model is taken as an example to demonstrate our findings.
- Published
- 2010
11. Flowfield initialization and approach to stationary conditions in unsteady combustion simulations
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Charles L. Merkle, Guoping Xia, and Chenzhou Lian
- Subjects
Materials science ,General Computer Science ,Meteorology ,Computation ,Flow (psychology) ,General Engineering ,Combustor ,Initial value problem ,Initialization ,Transient (oscillation) ,Mechanics ,Combustion ,Chamber pressure - Abstract
The initial transient leading to stationary conditions in unsteady combustion simulations is investigated by considering flow establishment in model combustors. Quiescent initial conditions with the chamber initially filled with an inert, hot gas are used to provide physically realistic starting conditions and robust, reliable combustion initiation. Transient processes are visualized by using a distinct initial fluid in the combustor whose concentration is tracked as it is expelled. The duration of the transient is shown to be dependent on the characteristic turn-over time for recirculation zones and the time for the chamber pressure to reach steady conditions. Substantial changes in the initial condition did not materially affect the length of the transient. Different combustor geometries changed the ratio of pressure equilibration time and species replenishment time, but did not have a major effect on the overall duration of the transient. Representative comparisons of the time-averaged, stationary results with experiment are presented to document the computations.
- Published
- 2010
12. Solution-limited time stepping to enhance reliability in CFD applications
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Charles L. Merkle, Chenzhou Lian, and Guoping Xia
- Subjects
Numerical Analysis ,Mathematical optimization ,Physics and Astronomy (miscellaneous) ,business.industry ,Applied Mathematics ,Courant–Friedrichs–Lewy condition ,Computational fluid dynamics ,Residual ,Upper and lower bounds ,Computer Science Applications ,Computational Mathematics ,Control theory ,Modeling and Simulation ,Convergence (routing) ,Sensitivity (control systems) ,Limit (mathematics) ,business ,Reliability (statistics) ,Mathematics - Abstract
A method for enhancing the reliability of implicit computational algorithms and decreasing their sensitivity to initial conditions without adversely impacting their efficiency is investigated. Efficient convergence is maintained by specifying a large global Courant (CFL) number while reliability is improved by limiting the local CFL number such that the solution change in any cell is less than a specified tolerance. The method requires control over two key issues: obtaining a reliable estimate of the magnitude of the solution change and defining a realistic limit for its allowable variation. The magnitude of the solution change is estimated from the calculated residual in a manner that requires negligible computational time. An upper limit on the local solution change is attained by a proper non-dimensionalization of variables in different flow regimes within a single problem or across different problems. The method precludes unphysical excursions in Newton-like iterations in highly non-linear regions where Jacobians are changing rapidly as well as non-physical results such as negative densities, temperatures or species mass fractions during the computation. The method is tested against a series of problems all starting from quiescent initial conditions to identify its characteristics and to verify the approach. The results reveal a substantial improvement in convergence reliability of implicit CFD applications that enables computations starting from simple initial conditions without user intervention.
- Published
- 2009
13. Failure analysis of thermal degradation of TIM during power cycling
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Chenzhou Lian, Frank L. Pompeo, Hsichang Liu, J. Bunt, H. Longworth, Kathryn C. Rivera, Shidong Li, Kamal K. Sikka, and Hongqing Zhang
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Stress (mechanics) ,Compressive strength ,Materials science ,business.industry ,Tearing ,Power cycling ,Silicon on insulator ,Structural engineering ,Adhesive ,business ,Chip ,Failure mode and effects analysis - Abstract
This paper discusses a thermal reliability testing experiment and failure analysis (FA) in 32nm SOI Si technology chip packages. Thermal performance of the TIM materials is monitored and physical failure analysis is performed on test vehicle packages post thermal reliability test. Thermomechanical modeling is conducted for different test conditions. TIM thermal degradation is observed at the chip center area in the batch of samples post power cycling (PC) test, while the TIM performance remains normal in the other batch of samples post thermal aging (TA) test. Physical FA findings after TIM bond line thickness measurement (at the chip corners and chip center) and unlidding to inspect the TIM surface morphology confirmed the failure mode is TIM to chip tearing. Finite element modeling results indicate significant difference of stress status in TIM and sealband adhesive between PC and TA test. The TIM experiences compressive stress during PC test, while it is in tensile stress during TA test.
- Published
- 2014
14. Flip chip assembly method employing differential heating/cooling for large dies with coreless substrates
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Mantilla Oswald J, Marcus E. Interrante, Edmund Blackshear, Katsuyuki Sakuma, Jae-Woong Nah, Chenzhou Lian, Tunga Krishna R, and Shidong Li
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Thermal copper pillar bump ,Materials science ,business.product_category ,Soldering ,Electronic engineering ,Die (manufacturing) ,Dielectric ,Composite material ,business ,Chip ,Temperature measurement ,Flip chip ,Thermal expansion - Abstract
In this work, differential heating/cooling chip join process was developed for coreless flip chip packaging to minimize warpage change of coreless substrates during the bonding process. A chip was vacuumed to a bonder head and a coreless substrate was vacuumed on a base plate and they were held at different elevated temperatures during the bonding process. The temperature difference provides a substantially matched thermal expansion between the silicon chip and the coreless substrate. This minimizes stress induced by low coefficient of thermal expansion (CTE) mismatch during flip chip assembly. Both thermal and mechanical modeling were performed to provide more detailed information about the temperature distributions and warpage levels for all package components during the chip join process. Mechanical modeling of the chip join process confirmed that by implementing differential heating/cooling chip join process the stresses within the solder bumps can be reduced by more than 20% and the stresses in the low-k layers within the chip can be reduced by more than 25%. Our evaluations used semiconductor chips with a known low-k dielectric and SnAg solder bumps. The size of the test chip was approximately 19 mm × 19 mm with less than 150 μm pitch. The coreless substrate was 55 mm × 55 mm with 8+1 layers. The samples were bonded with an optimized differential heating/cooling chip join process. The experimental results showed that there were no C4 (Controlled Collapsible Chip Connection) bumps bridging, non-wets, nor low-k delamination in the large die with coreless package. Reliability data showed no failures in any of the tested modules.
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- 2013
15. Development of a flexible chip infrared (IR) thermal imaging system for product qualification
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Kamal K. Sikka, Marc D. Knox, Xiaojin Wei, Alan J. Weger, and Chenzhou Lian
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Engineering ,Computer cooling ,business.industry ,Process (computing) ,Hardware_PERFORMANCEANDRELIABILITY ,Chip ,Power (physics) ,law.invention ,Microprocessor ,law ,Thermal ,Hardware_INTEGRATEDCIRCUITS ,Electronic engineering ,Wafer testing ,Wafer ,business - Abstract
A flexible and efficient chip Infrared (IR) thermal imaging system was implemented on the product manufacturing test platform by collaboration with the burn-in/wafer test, systems, process, and failure analysis teams. A liquid cooling cell was successfully designed and tested. The imaging system was applied to investigate some wafer probe power/thermal issues for server high end products. Furthermore, we applied the method of Spatially-resolved Imaging of Microprocessor Power (SIMP) [1] to translate the thermal map into a power map. Finally, we propose a new concept of product thermal qualification as a supplement and potential alternative to the traditional thermal test vehicle (TTV) qualification.
- Published
- 2012
16. Automatic Time Step Determination for Enhancing Robustness of Implicit Computational Algorithms
- Author
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Chenzhou Lian, Guoping Xia, and Charles L. Merkle
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business.industry ,Robustness (computer science) ,Computation ,Courant–Friedrichs–Lewy condition ,Reference vector ,Computational fluid dynamics ,Time step ,business ,Key issues ,Residual ,Algorithm ,Mathematics - Abstract
A method for enhancing the robustness of implicit computational algorithms without adversely impacting their efficiency is investigated. The method requires control over two key issues: obtaining a reliable estimate of the magnitude of the solution change and defining a realistic limit for its allowable variation. The magnitude of the solution change is estimated from the calculated residual in a manner that requires negligible computational time. An upper limit on the local solution change is attained by a proper non-dimensionalization of variables in different flow regimes within a single problem or across different problems. The method precludes unphysical excursions in Newton-like iterations in highly non-linear regions where Jacobians are changing rapidly as well as non-physical results during the computation. The method is tested against a series of problems to identify its characteristics and to verify the approach. The results reveal a substantial improvement in the robustness of implicit CFD applications that enables computations starting from simple initial conditions without user intervention.
- Published
- 2011
17. Adaptive and Consistent Properties Reconstruction for Complex Fluids Computation
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Guoping Xia, Charles L. Merkle, and Chenzhou Lian
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Equation of state ,business.industry ,Computation ,Mathematical analysis ,Perfect gas ,Computational fluid dynamics ,Thermodynamic equations ,symbols.namesake ,Helmholtz free energy ,Compressibility ,symbols ,Statistical physics ,business ,Reconstruction procedure ,Mathematics - Abstract
An efficient reconstruction procedure on adaptive Cartesian mesh for evaluating the constitutive properties of a complex fluid from general or specialized thermodynamic databases is presented. Reconstruction is accomplished on a triangular subdivision of the 2D Cartesian mesh covering thermodynamic plane of interest that ensures function continuity across cell boundaries to C 0 , C 1 or C 2 levels. The C 0 and C 1 reconstructions fit the equation of state and enthalpy relations separately, while the C 2 reconstruction fits the Helmholtz or Gibbs function enabling EOS/enthalpy consistency also. All three reconstruction levels appear effective for CFD. The time required for evaluations is approximately two orders of magnitude faster with the reconstruction procedure than with the complete thermodynamic equations. Storage requirements are modest for today’s computers, with the C 1 method requiring slightly less storage than those for the C 0 and C 2 reconstructions when the same accuracy is specified. Sample fluid dynamic calculations based upon the procedure show that the C 1 and C 2 methods are approximately a factor of two slower than the C 0 method but that the reconstruction procedure enables arbitrary fluid CFD calculations that are as efficient as those for a perfect gas or an incompressible fluid for all three accuracy levels.
- Published
- 2011
18. Investigation of Effects of Radial Distortion on Transonic Fan Behavior
- Author
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Guoping Xia, Dmytro M. Voytovych, Charles L. Merkle, and Chenzhou Lian
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Flow separation ,Materials science ,Meteorology ,Mass flow meter ,Turbulence ,Mass flow ,Mass flow rate ,Mechanics ,Total pressure ,Transonic ,Flow measurement - Abstract
The flow analysis around blades of a transonic fan is presented for both clean and radially distorted inlets. Computations are shown for four-blade passages that are accomplished with a second order accurate code using a k-ω turbulence model. The mass flow rate along a speed line is controlled by varying a choked nozzle downstream of the fan. The results show good agreement with data for three speed lines. In the near-stall region, the flow first becomes unsteady and then unstable with the unsteadiness increasing at lower speeds. The four-blade simulations remained stable to lower mass flow rates than the single-blade simulations. In the near-stall vicinity, tip vortex breakdown occurred creating a low momentum zone near the blade tip on the pressure side that grew as the mass flow was decreased until it eventually blocked the passage. The presence of distortion reduced the operational range and moved the stall line to higher mass flow rates. At high speeds distortion reduced both the mass flow rate and total pressure ratio while at lower speeds, the choking mass flow rate was reduced, but the total pressure ratio was slightly improved. The flow separation near the hub on the suction side was caused by the distortion. Its size was decreasing with rotational speed.Copyright © 2010 by ASME
- Published
- 2010
19. Effects of Back Step Height and Recirculation Zones on Mixing and Combustion
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Charles L. Merkle, Chenzhou Lian, and Guoping Xia
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Meteorology ,Chemistry ,Step height ,Combustion ,Atmospheric sciences ,Mixing (physics) - Published
- 2009
20. Flowfield Initialization and Approach to Stationary Conditions in Unsteady Combustion Simulations
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Charles L. Merkle, Dmytro M. Voytovych, Chenzhou Lian, and Guoping Xia
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Physics ,Stationary conditions ,Initialization ,Mechanics ,Combustion - Published
- 2009
21. Facility Development for Testing of Wave Rotor Combustion Rig
- Author
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Yu Matsutomi, Scott Meyer, Chenzhou Lian, Stephen D. Heister, Chris Hein, and Charles L. Merkle
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Gas turbines ,Engineering ,Test facility ,business.industry ,Rotor (electric) ,Mechanical engineering ,Combustion ,Pressure rise ,law.invention ,Volume (thermodynamics) ,Combustion process ,law ,Combustor ,business - Abstract
A Wave Rotor Combustion Rig (WRCR) is under development by a team including Purdue University, Rolls-Royce (LibertyWorks © ) and Indiana University-Purdue University. Theoretically, the wave rotor configuration provide s improved efficiency for gas turbine machines via a nearly constant volume combustion process that permits a significant pressure rise within the combustor. The objectives of the WRCR combustion experiment include concept verification and performance of the advanced combustor design for a turbomachinary-based engine. The Purdue team is responsible for development of the WRCR test facility as a part of this program and th is paper summarizes efforts relative to this aspect of the overall project.
- Published
- 2007
22. Numerical Simulation of Start-Up Jets in a Mixing Chamber.
- Author
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Chenzhou Lian, Voytovych, Dmytro M., Guoping Xia, and Merkle, Charles L.
- Subjects
HELIUM ,NUMERICAL analysis ,REYNOLDS number ,FLUID dynamics ,MECHANICS (Physics) - Abstract
Numerical simulations of the transient flow of helium injected into an established background flow of nitrogen were carried out to identify the dominant features of the transient mixing process between these two dissimilar gases. The geometry of interest is composed of two helium slots on either side of a central nitrogen channel feeding into a rectangular mixing chamber that was experimentally designed to give "two-dimensional" flow. Simulations were accomplished on both two- and three-dimensional grids. The 3D solutions employ an unsteady DES approach, while the 2D results are based upon a reduced dimension, "DES-like" method. Results are compared with quantitative experimental measurements of species distributions both in terms of contour plots and local point measurements. The 2D solutions give a reasonable qualitative picture of the transient mixing process in the center of the chamber while also providing quantitative estimates of representative characteristic times for guiding the 3D calculations. The 3D solutions give a reasonable approximation to span-wise variations observed in the experiment. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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