Airfoil Deflection Characteristics During Rub Events

2010 ◽  
Author(s):  
Kevin E. Turner ◽  
Michael Dunn ◽  
Corso Padova
Keyword(s):  
Adverse Effects ◽  
Gas Turbine ◽  
Ohio State University ◽  
Applied Force ◽  
Experimental Results ◽  
State University ◽  
The Ohio State University ◽  
Transient Forces ◽  
The Relationship ◽  
Key Parameter

The turbomachinery industry continually struggles with the adverse effects of contact rubs between airfoils and casings. The key parameter controlling the severity of a given rub event is the contact load produced when the airfoil tips incur into the casing. These highly non-linear and transient forces are difficult to calculate and their effects on the static and rotating components are not well understood. To help provide this insight, experimental and analytical capabilities have been established and exercised through an alliance between GE Aviation and The Ohio State University Gas Turbine Laboratory. One of the early findings of the program is the influence of blade flexibility on the physics of rub events. The focus of this paper is to quantify the influence of airfoil flexibility through a novel modeling approach that is based on the relationship between applied force duration and maximum tip deflection. Results from the model are compared to experimental results, providing sound verification.

Airfoil Deflection Characteristics During Rub Events

2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Kevin E. Turner ◽  
Michael Dunn ◽  
Corso Padova
Keyword(s):  
Adverse Effects ◽  
Gas Turbine ◽  
Ohio State University ◽  
Applied Force ◽  
State University ◽  
Highly Nonlinear ◽  
The Ohio State University ◽  
Transient Forces ◽  
The Relationship ◽  
Key Parameter

The turbomachinery industry continually struggles with the adverse effects of contact rubs between airfoils and casings. The key parameter controlling the severity of a given rub event is the contact load produced when the airfoil tips incur into the casing. These highly nonlinear and transient forces are difficult to calculate and their effects on the static and rotating components are not well understood. To help provide this insight, experimental and analytical capabilities have been established and exercised through an alliance between GE Aviation and The Ohio State University Gas Turbine Laboratory. One of the early findings of the program is the influence of blade flexibility on the physics of rub events. The focus of this paper is to quantify the influence of airfoil flexibility through a novel modeling approach that is based on the relationship between the applied force duration and maximum tip deflection. Results from the model are compared with experimental results, providing sound verification.

Effects of Timbre on College Woodwind Players' Intonational Performance and Perception

1992 ◽  
Vol 40 (2) ◽  
pp. 158-167 ◽  
Author(s):  
Mark C. Ely
Keyword(s):  
Ohio State University ◽  
Performance Data ◽  
State University ◽  
Performance Task ◽  
School Of Music ◽  
Low Correlation ◽  
Significant Difference ◽  
The Ohio State University ◽  
And Performance ◽  
The Relationship

The purpose of this study was to investigate the effects of timbre on musicians' intonational acuities during a listening and a performance task. Nine saxophonists, nine clarinetists, and nine flutists from The Ohio State University School of Music participated in the listening and performance segments of this experiment. The performance data consisted of subjects' intonational deviations from recorded examples, and the listening data consisted of subjects' correct and incorrect responses to in-tune or out-of-tune tone pairs. The relationship between subjects' abilities to perform in tune and detect intonation problems, and the effects of timbre on subjects' abilities to perform in tune and detect intonation problems were assessed. Results revealed a low correlation between subjects abilities to play in tune and their abilities to detect intonation problems. Results also indicated that timbre had a significant effect on subjects' abilities to detect intonation problems, but not on their abilities to play in tune. Although there was no significant difference between instrument groups' abilities to detect intonation problems, a significant difference was found between these groups' abilities to play in tune across all timbres. Subjects played significantly more flat than sharp when matching other instrument timbres.

scholarly journals Traumatic Brain Injury and Recidivism Among Returning Inmates

2017 ◽  
Vol 44 (3) ◽  
pp. 472-486 ◽  
Author(s):  
Bradley Ray ◽  
Nicholas J. Richardson
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
General Population ◽  
Justice System ◽  
Ohio State University ◽  
Policy Implications ◽  
Future Research ◽  
State University ◽  
The Ohio State University ◽  
The Relationship

In recent years, there has been a surge in research that examines the relationship between traumatic brain injury (TBI) and involvement in the criminal justice system. However, the bulk of this research has been largely retrospective and descriptive, comparing rates of TBI in the offending population with the rates of TBI in the general population. Although findings from these studies indicate a higher prevalence of TBI in the offending population, virtually no studies have examined whether those with TBI are more likely to recidivate. To address this gap, the present study examined rearrest post release from prison among a cohort sample of Indiana inmates who were screened using the Ohio State University Traumatic Brain Injury Identification (OSU-TBI-ID) instrument. Findings indicate that, net of control variables, those with TBI were more likely to recidivate sooner than those without TBI. Policy implications and directions for future research are discussed.

History of Short-Duration Measurement Programs Related to Gas Turbine Heat Transfer, Aerodynamics, and Aeroperformance at Calspan and The Ohio State University

2013 ◽  
Vol 136 (4) ◽  
Author(s):  
Michael Dunn ◽  
Randall Mathison
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Gas Turbine ◽  
Short Duration ◽  
Ohio State University ◽  
Experimental Techniques ◽  
Experimental Program ◽  
State University ◽  
Purge Flow ◽  
The Ohio State University

Short-duration facilities have been used for the past 35 years to obtain measurements of heat transfer, aerodynamic loading, vibratory response, film-cooling influence, purge flow migration, and aeroperformance for full-stage, high-pressure turbines operating at design-corrected conditions of flow function, corrected speed, and stage pressure ratio. This paper traces the development of experimental techniques now in use at The Ohio State University (OSU) Gas Turbine Laboratory (GTL) from initial work in this area at the Cornell Aeronautical Laboratory (CAL, later to become Calspan) from 1975 through to the present. It is intended to summarize the wide range of research that can be performed with a short-duration facility and highlight the types of measurements that are possible. Beginning with heat flux measurements for the vane and blade of a Garrett TFE 731-2 HP turbine stage with vane pressure-surface slot cooling, the challenge of each experimental program has been to provide data to aid turbine designers in understanding the relevant flow physics and help drive the advancement of predictive techniques. Through many different programs, this has involved collaborators at a variety of companies and experiments performed with turbine stages from Garrett, Allison, Teledyne, Pratt and Whitney (P/W), General Electric Aviation (GEA), Rocketdyne, Westinghouse, and Honeywell. The vane/blade interaction measurement and computational fluid dynamics (CFD) program, which ran from the early 1980s until 2000, provided a particularly good example of what can be achieved when experimentalists and computational specialists collaborate closely. Before conclusion of this program in 2000, the heat flux and pressure measurements made for this transonic turbine operated with and without vane trailing edge cooling flow were analyzed and compared to predictive codes in conjunction with engineers at Allison, United Technologies Research Center (UTRC), P/W, and GEA in jointly published papers. When the group moved to OSU in 1995 along with the facility used at Calspan, refined techniques were needed to meet new research challenges, such as investigating blade-damping and forced response, measuring aeroperformance for different configurations, and preparing for advanced cooling experiments that introduced complicating features of an actual engine to further challenge computational predictions. This required conversion of the test-gas heating method from a shock-tunnel approach to a blowdown approach using a combustor emulator to also create inlet temperature profiles, the development of instrumentation techniques to work with a thin-walled airfoil with backside cooling, and the adoption of experimental techniques that could be used to successfully operate fully cooled turbine stages (vane row-cooled, blade row-cooled, and proper cavity purge flow provided). Further, it was necessary to develop techniques for measuring the aeroperformance of these fully cooled machines.

Five Decades of Research Experience in Speech Anatomy and Physiology

2016 ◽  
Vol 1 (5) ◽  
pp. 4-12
Author(s):  
David P. Kuehn
Keyword(s):  
Ohio State University ◽  
State University ◽  
Research Experience ◽  
University Of Iowa ◽  
University Of Illinois ◽  
Anatomy And Physiology ◽  
The Ohio State University ◽  
Speech Science ◽  
The University ◽  
East Carolina University

This report highlights some of the major developments in the area of speech anatomy and physiology drawing from the author's own research experience during his years at the University of Iowa and the University of Illinois. He has benefited greatly from mentors including Professors James Curtis, Kenneth Moll, and Hughlett Morris at the University of Iowa and Professor Paul Lauterbur at the University of Illinois. Many colleagues have contributed to the author's work, especially Professors Jerald Moon at the University of Iowa, Bradley Sutton at the University of Illinois, Jamie Perry at East Carolina University, and Youkyung Bae at the Ohio State University. The strength of these researchers and their students bodes well for future advances in knowledge in this important area of speech science.

Cardiology Fellowship Education in the Era of High-density Training, Data Tracking, and Quality Measures

2011 ◽  
Vol 9 (2) ◽  
pp. 99
Author(s):  
Alex J Auseon ◽  
Albert J Kolibash ◽  
◽  
Keyword(s):  
Ohio State University ◽  
Training Data ◽  
State University ◽  
Training Requirements ◽  
Healthcare Environment ◽  
Medical Centers ◽  
Work Hour ◽  
The Ohio State University ◽  
Data Tracking

Background:Educating trainees during cardiology fellowship is a process in constant evolution, with program directors regularly adapting to increasing demands and regulations as they strive to prepare graduates for practice in today’s healthcare environment.Methods and Results:In a 10-year follow-up to a previous manuscript regarding fellowship education, we reviewed the literature regarding the most topical issues facing training programs in 2010, describing our approach at The Ohio State University.Conclusion:In the midst of challenges posed by the increasing complexity of training requirements and documentation, work hour restrictions, and the new definitions of quality and safety, we propose methods of curricula revision and collaboration that may serve as an example to other medical centers.

Evaluation of a New Clinical Test of Fusion Status: A Pilot Study

2019 ◽  
pp. 113-118
Keyword(s):  
Pilot Study ◽  
Ohio State University ◽  
Background Suppression ◽  
Clinical Test ◽  
State University ◽  
Chi Square ◽  
Central Fusion ◽  
Eye Examination ◽  
The Ohio State University ◽  
Chi Square Analysis

Background Suppression is associated with binocular vision conditions such as amblyopia and strabismus. Commercial methods of testing fusion often only measure central fusion or suppression at near. The purpose of this pilot study was to assess a new iPad picture fusion test that assesses foveal and central fusion at near. Methods Participants aged 5 years and older presenting for eye examination at The Ohio State University College of Optometry were enrolled. Results from visual acuity, dry and wet refraction/retinoscopy, stereopsis and cover testing were recorded from the patient chart. The iPad picture fusion test, Worth four-dot, Worth type test with foveal letter targets, and Polarized four-dot were performed by one examiner in a randomized order at 40 cm. Testing was repeated with the anaglyphic filters reversed. Crosstabulation and McNemar chi-square analysis were used to compare the results between fusion testing devices. Results Of the fifty participants (mean age = 17.5), twelve reported suppression and one reported diplopia. Testability was excellent for all tests (98% to 100%). There were no significant differences between tests in reported results (P ≥ 0.22 for all comparisons). No difference in reported fusion or suppression status was observed with change in orientation of the anaglyphic filters. Six participants reported foveal suppression alone at near which was not identified with Worth four-dot at near. Conclusion The iPad picture fusion test provided excellent testability and agreement with commonly used tests of fusion and allowed testing of both central and foveal fusion at near. Nearly half (46%) of participants with suppression reported foveal suppression, supporting the importance of testing for foveal suppression.

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