Academic literature on the topic 'Mental rotations test'
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Journal articles on the topic "Mental rotations test"
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Monahan, John S., Maureen A. Harke, and Jonathon R. Shelley. "Computerizing the Mental Rotations Test: Are gender differences maintained?" Behavior Research Methods 40, no. 2 (May 2008): 422–27. http://dx.doi.org/10.3758/brm.40.2.422.
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Cooke-Simpson, Amanda, and Daniel Voyer. "Confidence and gender differences on the Mental Rotations Test." Learning and Individual Differences 17, no. 2 (April 2007): 181–86. http://dx.doi.org/10.1016/j.lindif.2007.03.009.
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Titze, Corinna, Martin Heil, and Petra Jansen. "Gender Differences in the Mental Rotations Test (MRT) Are Not Due to Task Complexity." Journal of Individual Differences 29, no. 3 (January 2008): 130–33. http://dx.doi.org/10.1027/1614-0001.29.3.130.
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Gender differences are one of the main topics in mental rotation research. This paper focuses on the influence of the performance factor task complexity by using two versions of the Mental Rotations Test (MRT). Some 300 participants completed the test without time constraints, either in the regular version or with a complexity reducing template creating successive two-alternative forced-choice tasks. Results showed that the complexity manipulation did not affect the gender differences at all. These results were supported by a sufficient power to detect medium effects. Although performance factors seem to play a role in solving mental rotation problems, we conclude that the variation of task complexity as realized in the present study did not.
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Malinowski, Jon C. "Mental Rotation and Real-World Wayfinding." Perceptual and Motor Skills 92, no. 1 (February 2001): 19–30. http://dx.doi.org/10.2466/pms.2001.92.1.19.
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Sex differences in mental rotation skills are a robust finding in small-scale laboratory-based studies of spatial cognition. There is almost no evidence in the literature, however, relating these skills to performance on spatial tasks in large-scale, real-world activities such as navigating in a new city or in the woods. This study investigates the connections between mental rotation skills as measured by the Vandenburg-Kuse Mental Rotations test and the performance of college students ( n = 211) navigating a 6-km orienteering course. The results indicate that mental rotation skills are significantly correlated with wayfinding performance on an orienteering task. The findings also replicate sex differences in spatial ability as found in laboratory-scale studies. However, the findings complicate the discussion of mental rotation skills and sex because women often performed as well as men despite having lower mean test scores. This suggests that mental rotation ability may not be as necessary for some women's wayfinding as it is for men's navigation.
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Voyer, Daniel, and Randi A. Doyle. "Item type and gender differences on the Mental Rotations Test." Learning and Individual Differences 20, no. 5 (October 2010): 469–72. http://dx.doi.org/10.1016/j.lindif.2010.04.010.
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Voyer, Daniel, and Kristin A. Saunders. "Gender differences on the mental rotations test: a factor analysis." Acta Psychologica 117, no. 1 (September 2004): 79–94. http://dx.doi.org/10.1016/j.actpsy.2004.05.003.
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Talbot, Karyn F., and Richard H. Haude. "The Relation between Sign Language Skill and Spatial Visualization Ability: Mental Rotation of Three-Dimensional Objects." Perceptual and Motor Skills 77, no. 3_suppl (December 1993): 1387–91. http://dx.doi.org/10.2466/pms.1993.77.3f.1387.
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The present study was designed to ascertain whether a relationship exists between the experience of an individual in American Sign Language (ASL) and performance on the Mental Rotations Test. 51 women were divided into three groups on the basis of self-reported ASL skill (years of experience). All subjects then completed the Mental Rotations Test, a paper-and-pencil test of spatial ability. The State-Trait Anxiety Inventory was also administered to examine possible apprehension about evaluation. Significant differences in scores on mental rotations were found, with 18 experienced signers scoring significantly higher than either mean of the two less experienced groups ( ns = 16 and 17). It appears that people experienced in ASL perform better on the Mental Rotations Test. No evidence for a difference in anxiety related to the amount of experience a person had in ASL was found.
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Morrison, Craig S., and Christina M. Frederick. "Relationship of Initial and Final Scores on a Qualitative Analysis of Movement Test." Perceptual and Motor Skills 87, no. 2 (October 1998): 651–55. http://dx.doi.org/10.2466/pms.1998.87.2.651.
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The present study examined the relationship of initial qualitative analysis of movement scores, disembedding scores, and mental rotation scores on terminal qualitative analysis of movement scores. The subjects were 19 female and 17 male undergraduate majors in physical education, 14 from Oklahoma State University and 22 from Southern Utah University, with a mean age of 23.0 ± 4.5 yr. The test and instructional unit on qualitative analysis of movement were developed by Morrison and Harrison in 1985. The Group Embedded Figures Test was used to discern disembedding scores and the Mental Rotations Test scores on mental rotation. The means and standard deviations for the pretest and posttest measures on the movement analysis test were 72.08 ± 7.06 and 78.30 ±4.21. Analysis indicated instruction improved scores on the qualitative analysis test. Also, initial movement test scores and those on disembedding were significant predictors of scores on the posttest qualitative analysis of movement but not of mental rotation test scores.
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Ginn, Sheryl R., and Stefanie J. Pickens. "Relationships between Spatial Activities and Scores on the Mental Rotation Test as a Function of Sex." Perceptual and Motor Skills 100, no. 3 (June 2005): 877–81. http://dx.doi.org/10.2466/pms.100.3.877-881.
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Previous results suggested that female college students' scores on the Mental Rotations Test might be related to their prior experience with spatial tasks. For example, women who played video games scored better on the test than their non-game-playing peers, whereas playing video games was not related to men's scores. The present study examined whether participation in different types of spatial activities would be related to women's performance on the Mental Rotations Test. 31 men and 59 women enrolled at a small, private church-affiliated university and majoring in art or music as well as students who participated in intercollegiate athletics completed the Mental Rotations Test. Women's scores on the Mental Rotations Test benefitted from experience with spatial activities; the more types of experience the women had, the better their scores. Thus women who were athletes, musicians, or artists scored better than those women who had no experience with these activities. The opposite results were found for the men. Efforts are currently underway to assess how length of experience and which types of experience are related to scores.
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Quinn, Paul C., and Lynn S. Liben. "A Sex Difference in Mental Rotation in Young Infants." Psychological Science 19, no. 11 (November 2008): 1067–70. http://dx.doi.org/10.1111/j.1467-9280.2008.02201.x.
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Three- to 4-month-old female and male human infants were administered a two-dimensional mental-rotation task similar to those given to older children and adults. Infants were familiarized with the number 1 (or its mirror image) in seven different rotations between 0° and 360°, and then preference-tested with a novel rotation of the familiar stimulus paired with its mirror image. Male infants displayed a novelty preference for the mirror-image stimulus over the novel rotation of the familiar stimulus, whereas females divided attention between the two test stimuli. The results point toward an early emergence of a sex difference in mental rotation.
Dissertations / Theses on the topic "Mental rotations test"
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Penk, Mildred Lotus. "Mental Imagery: The Road to Construct Validity." Thesis, University of North Texas, 1988. https://digital.library.unt.edu/ark:/67531/metadc331872/.
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Internal consistency reliability and validity were established for a new 31 item Imagery Manipulation Scale. Previous attempts to correlate subjectively rated control of visual imagery with tests of spatial ability have been unsuccessful. However, no attempt to construct a subjectively rated control of imagery scale was located which tried to establish internal consistency reliability and both content and construct validity. Further, no research was located in which subjects were requested to rate their imagery ability utilized during the performance of the actual spatial tasks used to try to establish validity. A new scale of subjectively rated control of imagery was devised in which subjects were requested to rate their imagery while solving spatial tasks which involved visualizing the manipulation of geometric forms. Content validity was established by analyzing the transformation involved while solving the spatial problems. Internal consistency reliability for the 31 item scale was established across two samples. Validity was established with the second sample (100 university students: 26 male and 74 female). The task utilized to provide validity could be objectively scored, and was made up of four spatial subtests, which were adapted from the Vandenberg and Kuse Mental Rotations Test, the Kosslyn Directions Test, performed in both the forward and backward direction, and a block task utilized by Snyder. A convergent and discriminant validity analysis established construct validity. Further, the hypotheses of three investigators, Kosslyn, Shepard and his colleagues, and Snyder, were supported by the results of the present investigation, thus substantiating the conclusion that reported control of imagery processing can be operationalized with performance scores on spatial ability tasks.
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Bruckner, Terri Ann. "Using an Argument-based Approach to Validity for Selected Tests of Spatial Ability in Allied Medical Professions Students." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1371562493.
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Duranceau, Alexandra. "La différence dans les performances visuo-spatiales des résidents en chirurgie et celles d'un groupe contrôle." Thèse, 2005. http://hdl.handle.net/1866/15445.
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Shukla, Sonia. "Gender differences on the Mental Rotations Test: Examining the role of instructions and participant characteristics." 2006. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=442065&T=F.
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Titze, Corinna [Verfasser]. "Psycho-soziale und testspezifische Einflüsse auf den Geschlechtseffekt beim Lösen des psychometrischen "Mental-Rotations-Test" / vorgelegt von Corinna Titze." 2010. http://d-nb.info/1007842377/34.
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Kaye, Blaize Michael. "Tetris and mental rotation." Thesis, 2013. http://hdl.handle.net/10413/9301.
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Research has shown a possible causative link between playing the popular videogame
Tetris and improvements in Mental Rotation performance. The aim of the
present study was to address a question about an aspect of Tetris expertise that
had not yet been factored into any of the existing work on Tetris and Mental
Rotation. David Kirsh and Paul Maglio (1994) have shown that skilled Tetris
players appear to use physical actions as substitutes for, or compliments to,
mental operations. This is hypothesised to include physically rotating game
pieces instead of Mentally Rotating them. The specific question we sought to
address in the present study was whether these physical substitutes for mental
operations, which Kirsh and Maglio call epistemic actions, have an effect on
Tetris' efficacy as a Mental Rotation training task.
In order to address this research question, three groups of subjects were administered
tests of Mental Rotation ability before and after a five week training
period. The training period consisted of a total of five, hour long, laboratory
sessions - evenly spaced across the training period - in which each of the
three groups were required to play an assigned video-game. The results showed
that a group of subjects (N=13) who received Tetris training on the version of
the game that made epistemic actions involving rotation impossible showed no
greater Mental Rotation performance gains when their results were compared to
a group of subjects (N=13) trained using a Standard version of Tetris. This suggests
that the occurence of epistemic actions does not have an impact on Tetris'
efficacy as a Mental Rotation training task. Further, neither of these two groups
showed greater Mental Rotation performance gains than the non-Tetris control
group (N=14), a result which suggests that, at least under some circumstances,
Tetris training fails to impart Mental Rotation performance gains any greater
than what can be expected due to retest effects.Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2013.
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Liu, Giun-Fu, and 劉俊甫. "The Comparisons of Performances in the Two-dimensional and Three-dimensional Computerized Mental Rotation Test." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/8f7bv8.
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碩士國立臺灣科技大學
數位學習與教育研究所
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The study explored the effects of dimensionality of the mental rotation test items on the subjects’ performance, and took grades and genders into account to observe their potential interaction effects. There were 452 students of grades four, five, and six. The computerized mental rotation test was consisted of 10 pairs of 20 items, having the same item being presented in traditional 2D and 3D dynamic formats and resulting in two items as a pair. With this design, the subjects received both 2D and 3D dynamic items, therefore the repeated measures three-way analysis of variances was adopted to analyze the test scores and test time. The results showed that, there was no significant three-way interaction at all. For test scores, there were no significant two-way interaction and no main effect of dimensionality, the test scores of grades five and six were higher than those of grade four, and the boys’ test scores were higher than the girls’. As for the test time, there were significant two-way interaction between dimensionality and genders, and genders and grades, resulting in that the girls’ test time was more than the boys’ in grade five, the boys’ test time in grades five and six were more than their grade four, and the girls’ test time in grade five was more than their grades four and six. Moreover, the correlation coefficients between test scores and test time were positive in all grouping conditions, meaning that the higher the test score is, the more the test time required, and vice versa. The main conclusions were that, there were gender and grade differences in mental rotation scores, that is, boys were higher than girls, and test scores were significantly higher since grade five for both genders, which implied that the mental rotation started to differentiate during the puberty. The conclusions also suggested significant two-way interaction in test time, but the 3D dynamic format may decrease the cognitive loading and gender differences in test time, and both genders manifest the largest difference of test time required in grade five only. The positive correlation between test scores and time suggested that the time limit would be crucial in subjects’ performance. The conclusions suggested that, for the dimensionality of presentation, it is necessary to consider the speed of recognition, gender and age differences, and to adaptively arrange the materials, media, designs and time limit in teaching, training, testing, games, propaganda, and public safety and alert signs.
Books on the topic "Mental rotations test"
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Shukla, Sonia. Gender differences on the Mental Rotations Test: Examining the role of instructions and participant characteristics. 2006.
Find full textBook chapters on the topic "Mental rotations test"
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Wyeld, Theodor, and Benedict Williams. "A Non-domain Specific Spatial Ability Test for Gamers Using Drawing and a Mental Rotation Task." In Computer-Human Interaction. Cognitive Effects of Spatial Interaction, Learning, and Ability, 114–32. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-16940-8_6.
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Boucheix, Jean-Michel, and Madeline Chevret. "Alternative Strategies in Processing 3D Objects Diagrams: Static, Animated and Interactive Presentation of a Mental Rotation Test in an Eye Movements Cued Retrospective Study." In Diagrammatic Representation and Inference, 138–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-44043-8_17.
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"Space Representation and Gender Differences." In A Simplex Approach to Learning, Cognition, and Spatial Navigation, 23–28. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-2455-7.ch003.
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Scientific literature highlighted gender differences in spatial orientation. In particular, men and women differ in terms of the navigational processes they use in daily life. Scientific literature highlighted that women use analytical strategies while men tend to use holistic strategies. According to classical studies, males show a net advantage at least in the two categories of mental rotation and spatial perception. Subsequently, brain-imaging studies have shown a difference between males and females in the activity of brain regions involved in spatial cognition tasks. What we can say with certainty is that, given the complex nature of the subprocesses involved in what we call spatial cognition, the gender differences recorded by numerous scientific studies conducted in this field are closely related to specific measured abilities. The evidence that emerges with certainty from diverse studies is, however, that of a huge variety of strategies that differ according to sex, context, purpose to reach, education, age, and profession. In the study presented here, the gender and age-related tests show a significant sex-based difference perspective-taking tasks, but there is no gender-based difference in the mental rotation task.
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Metcalfe, David, and Harveer Dev. "Tips for the SJT." In Oxford Assess and Progress: Situational Judgement Test. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198805809.003.0017.
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1. Put yourself in the position of a new FY1 doctor when answering each question. But remember that they are asking what you should do, not what you would do. 2. You should be a paragon of virtue when answering all questions. Remember always that you are unfailingly honest, respectful, open, and fair to colleagues, patients, and relatives alike. It is difficult to imagine scenarios with answers that would require you to be otherwise. 3. If a question involves patient safety (e.g. critically unwell patient, drug error, etc.), your priority must always be making the patient safe. 4. The well- being of your patient is your first priority. Other considerations (e.g. relatives, targets, fear of being told off, going home on time) are always secondary. 5. ‘Seeking senior advice’ and ‘gathering information’ are difficult to criticize and tend to be safe options. Similarly, it is rarely incorrect to document events or complete a formal incident form. 6. Remember your limitations. As an FY1 doctor, you should not usually break bad news, consent patients for operations, administer cytotoxic or anaesthetic drugs, or manage critically ill patients without support. ‘Call a senior’ is the correct answer in these cases. 7. Understand basic concepts of medical law, e.g. when confidentiality can be breached, determining incapacity, consent in children, the doctrine of double effect, and detention under the Mental Health Act. You do not need to know specifics (e.g. sections of Acts), but a practical understanding will guide some answers. 8. As an FY1 doctor, your Clinical Supervisor is usually a consultant for whom you work during a particular rotation. They are an appropriate source of support for clinical development and problems within the team. Your Educational Supervisor is akin to a Personal Tutor, i.e. responsible for your overall welfare and development throughout the year. They can advise on pastoral issues, professional development, and difficulties with your Clinical Supervisor. 9. Try to complete all questions within the given time frame as random guesses may be identified by the scoring software and awarded zero.
Conference papers on the topic "Mental rotations test"
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Williams, Christopher B., John Gero, Yoon Lee, and Marie Paretti. "Exploring Spatial Reasoning Ability and Design Cognition in Undergraduate Engineering Students." In ASME 2010 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/detc2010-28925.
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This paper presents preliminary results from the first phase of a longitudinal study of design cognition and the effects of design education on design practice. The study aims to monitor the development of engineering design thinking through a three-year protocol study of control and experimental groups of engineering students. Using innovations in cognitive science that include ontologically-based coding of protocols and new methods of protocol analysis, the study is intended to characterize students’ cognitive development, identify differences over time, and relate those differences to students’ educational experiences. The first phase of this study focuses on assessing students’ spatial reasoning ability. Spatial reasoning is the ability to process and form ideas through spatial relationships among objects. It has been found to correlate strongly with the design ability associated with one’s ability to generate, conceptualize, and communicate solutions to problems. Sophomore students entering two different majors took four spatial reasoning tests (Paper Folding, Vandenberg, Mental Rotation, and Spatial Imagery Ability) that addressed their ability to visualize objects and mentally manipulate them over an ordered sequence of spatial transformations. The results of these tests are presented in this paper. Tests were conducted to determine statistical significance in order to evaluate whether a student’s spatial reasoning ability correlates with their choice of engineering major. The students’ test performances are also compared with existing data from other fields (e.g., architecture, visual arts, science, and humanities).
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Zorn, Stefan, and Kilian Gericke. "Development of Spatial Abilities in Engineering Education: An Empirical Study of the Influence of Visualisation Media." In ASME 2020 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/detc2020-22428.
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Abstract Spatial ability is one of the critical components of human intelligence. It has been proven that it is particularly crucial for success, especially in engineering, where interpreting views of an object presented by drawings, visualizing parts, or manipulating geometry in CAD are fundamental skills. Research has confirmed that spatial skills can be improved through instruction and teaching, for example, sketching and technical drawing, which are also included in the basic engineering classes. This study tested the hypothesis that the development of spatial skills during the fundamental design engineering class can be positively influenced due to the use of different visualization media for sketching and technical drawing tasks, whereas the used visualization media offer varying possibilities of interaction. Seventy students were pre- and post-tested with the Mental Rotation Test. All participants received the same training during the class but were given individual tasks with varying media. The analysis revealed a significant increase in mental rotation performance for all participants throughout the semester with a big effect size. Moreover, the mean performance improvement differed considerably depending on the visualization media and its offered interaction possibilities.
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Yuan, Youming, and David Hunt. "Rotating Annulus Component Performance Characterisation Based on CFD Analyses." In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-75158.
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FloMASTER is a 1-D thermo-fluids system simulation tool and its component models depend on the characterisation data of the component performance. Such performance data is mainly based on data banks established from extensive tests exemplified by the books like “Internal Flow” by Miller [1] and “Handbook of Hydraulic Resistance” by Idelchik [2]. One of the key components of the gas turbine secondary air system is the rotating annulus. However, reliable data and correlations for performance characteristics like pressure loss coefficient, torque coefficient, windage and heat transfer for this component are rare and non-existent in the open literature for the case of both walls rotating simultaneously, which is becoming more common in today’s multi-spool military aero engines. To overcome this challenge of lack of reliable performance data and correlations, in this paper the Mentor Graphics 3D CFD tool “FloEFD” is used to model both inner wall rotating and outer wall rotating annulus flow, and to verify the 3D CFD results of performance data in terms of pressure loss coefficient and torque coefficient versus some published test data in the open literature. It is shown that the CFD gives results on pressure loss and torque coefficients that are in good agreement with test data based correlations used in FloMASTER. This demonstrates that 3D CFD can be used as a powerful tool for verifying the existing 1D model, extending the 1D model performance data range and generating new performance data for developing new components where such data is not available from open literature. A future project is to extend this approach to provide performance data for rotating annuli with both walls rotating. Such data will form the basis for developing a new component model for a rotating annulus with both walls rotating.
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Borello, Domenico, Giovanni Delibra, Cosimo Bianchini, and Antonio Andreini. "Unsteady CFD Analysis of Turbulent Flow and Heat Transfer in a Gas Turbine Blade Trailing Edge Subjected to Rotation." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69903.
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Internal cooling of gas turbine blade represents a challenging task involving several different phenomena as, among others, highly three-dimensional unsteady fluid flow, efficient heat transfer and structural design. This paper focuses on the analysis of the turbulent flow and heat transfer inside a typical wedge–shaped trailing edge cooling duct of a gas turbine blade. In the configuration under scrutiny the coolant flows inside the duct in radial direction and it leaves the blade through the trailing edge after a 90 deg turning. At first an analysis of the flow and thermal fields in stationary conditions was carried out. Then the effects of rotational motion were investigated for a rotation number of 0.275. The rotation axis here considered is normal to the inflow and outflow bulk velocity, representing schematically a highly loaded blade configuration. The work aimed to i) analyse the dynamic of the vortical structures under the influence of strong body forces and the constraints induced by the internal geometry and ii) to study the impact of such motions on the mechanisms of heat removal. The final aim was to verify the design of the equipment and to detect the possible presence of regions subjected to high thermal loads. The analysis is carried out using the well assessed open source code OpenFOAM written in C++ and widely validated by several scientists and researchers around the world. The unsteadiness of the flow inside the trailing edge required to adopt models that accurately reconstructed the flow field. As the computational costs associated to LES (especially in the near wall regions) largely exceed the available resources, we chose for the simulation the SAS model of Menter, that was validated in a series of benchmark and industrially relevant test cases and allowed to reconstruct a part of the turbulence spectra through a scale-adaptive mechanism. Assessment of the obtained results with steady-state k-ω SST computations and available experimental results was carried out. The present analysis demonstrated that a strong unsteadiness develops inside the trailing edge and that the rotation generated strong secondary motions that enhanced the dynamic of heat removal, leading to a less severe temperature distribution on the heated surface w.r.t the non rotating case.
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Farisco, Federica, Stefan Rochhausen, Metin Korkmaz, and Michael Schroll. "Validation of Flow Field and Heat Transfer in a Two-Pass Internal Cooling Channel Using Different Turbulence Models." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-95461.
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In this work the flow regime within a generic turbine cooling system is investigated numerically. The main objective is to validate the performance of various turbulence models with different complexity by comparing the numerical results with experimental data. To maximize surface heat transfer rates, present-day cooling systems of high pressure turbines have highly complex shapes generating high turbulence levels and flow separations. These flow structures lead to higher requirements of CFD-techniques for sufficient prediction. To simulate complex flows in the industrial design process, Reynolds averaged Navier-Stokes (RANS) techniques are applied instead of computationally expensive LES and DNS simulations. Therefore, higher order turbulence models are necessary to predict flow field and heat transfer performance in such complex motion. The DLR standard flow solver for turbomachinery flows, TRACE, is used to solve the RANS equations. Four turbulence models have been analysed: the one equation model of Spalart and Allmaras, the two equation k – ω model of Wilcox, the two equation k – ω SST model of Menter and the anisotropy resolving Explicit Algebraic Reynolds Stress model (EARSM) of Hellsten. The investigated cooling geometry consists of a two-pass smooth channel with a 180 degree bend. At the DLR institute of propulsion technology PIV measurements in a rotating cooling channel test bed for Rotation numbers up to 0.1 have been performed. This work uses the experimental data for Re = 50,000 and Ro = 0 without rotation for comparison. For all models adiabatic and diabatic calculations have been performed. In order to accurately apply the turbulence models, a study concerning the turbulent boundary conditions has been performed prior to the calculations. The results obtained through RANS simulations are presented in comparison with the experiments along planes in the flow direction and in the orthogonal direction to study the velocity field, the shape and size of the separation bubbles and the wall shear stress. The EARSM predicts the flow field overall more accurately with improved agreement between all relevant parameters compared to the other models. The diabatic simulations reflect the adiabatic results. However, it can be noticed that higher complexity in turbulence modelling is related to increased heat transfer. Our work confirms the EARSMs ability to predict complex flow structures better than the more elementary approaches.
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Aziz, Ayesha, and Nashi Khan. "PERCEPTIONS PERTAINING TO STIGMA AND DISCRIMINATION ABOUT DEPRESSION: A FOCUS GROUP STUDY OF PRIMARY CARE STAFF." In International Psychological Applications Conference and Trends. inScience Press, 2021. http://dx.doi.org/10.36315/2021inpact013.
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"The present study was conducted to explore the perception and views of primary care staff about Depression related Stigma and Discrimination. The Basic Qualitative Research Design was employed and an In-Depth Semi-Structured Discussion Guide consisted of 7 question was developed on the domains of Pryor and Reeder Model of Stigma and Discrimination such as Self-Stigma, Stigma by Association, Structural Stigma and Institutional Stigma, to investigate the phenomenon. Initially, Field Test and Pilot study were conducted to evaluate the relevance and effectiveness of Focus Group Discussion Guide in relation to phenomena under investigation. The suggestions were incorporated in the final Discussion Guide and Focus Group was employed as a data collection measure for the conduction of the main study. A purposive sampling was employed to selected a sample of Primary Care Staff (Psychiatrists, Medical Officers, Clinical Psychologists and Psychiatric Nurses) to elicit the meaningful information. The participants were recruited from the Department of Psychiatry of Pakistan Medical and Dental Council (PMDC) recognized Private and Public Sector hospitals of Lahore, having experience of 3 years or more in dealing with patients diagnosed with Depression. However, for Medical Officers, the experience was restricted to less than one year based on their rotation. To maintain equal voices in the Focus Group, 12 participants were approached (3 Psychiatrist, 3 Clinical Psychologists, 3 Medical Officers and 3 Psychiatric Nurses) but total 8 participants (2 Psychiatrists, 2 Medical Officers, 3 Clinical Psychologists And 1 Psychiatric Nurse) participated in the Focus Group. The Focus Group was conducted with the help of Assistant Moderator, for an approximate duration of 90 minutes at the setting according to the ease of the participants. Further, it was audio recorded and transcribed for the analysis. The Braun and Clarke Reflexive Thematic Analysis was diligently followed through a series of six steps such as Familiarization with the Data, Coding, Generating Initial Themes, Reviewing Themes, Defining and Naming Themes. The findings highlighted two main themes i.e., Determining Factors of Mental Health Disparity and Improving Treatment Regimen: Making Consultancy Meaningful. The first theme was centered upon three subthemes such as Lack of Mental Health Literacy, Detached Attachment and Components of Stigma and Discrimination. The second theme included Establishing Contact and Providing Psychoeducation as a subtheme. The results manifested the need for awareness-based Stigma reduction intervention for Primary Care Staff aims to provide training in Psychoeducation and normalization to reduce Depression related Stigma and Discrimination among patients diagnosed with Depression."
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Tan, Qinxue, Jing Ren, and Hongde Jiang. "Prediction of 3D Unsteady Flow and Heat Transfer in Rotating Cavity by Discontinuous Galerkin Method and Transition Model." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26584.
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Rotating cavities with axial throughflow are found inside the compressor rotors of turbo-machines. The flow pattern and heat transfer in the cavities are known as sophisticated problems. Because of the numerical errors and model errors, as well as the stiffness introduced by low-Ma number, prediction of 3D unsteady flow and heat transfer in rotating cavity is still a challenge for modern CFD technology. An in-house 3D unsteady CFD code was developed in this study. The discontinuous galerkin method, which can fulfill any high-order accuracy on the unstructured grid, was applied to reduce the discretization errors. The SST-γ-Reθ transition model proposed by Menter was applied to reduce the model errors. To overcome the stiffness and achieve good convergence characteristics and solution quality, the preconditioning matrix technique combined with DG method was introduced for low-Ma number viscous flow. First, natural convection of air in a square cavity was studied to test the code. The feasibility and credibility, of applying the DG method and the preconditioned matrix technique for buoyancy–induced Rayleigh-Bénard like flow, were further verified. Second, the 3D compressible flow field in a rotating cavity was investigated numerically using the FV method, DG method and laminar/SA/SST-transition turbulence model. It is demonstrated that the whole flow structure of all calculated cases was similar after comparing the calculated results with the available experimental data. But, the transition turbulence model fitted the experimental data better. On the other hand, the performance of high-order method was much better for both the rotating cavity flow and natural convection, in terms of heat transfer. To better understand this phenomenon, an accuracy analysis of heat flux using DG method and FV method was performed. It showed the DG method could realize arbitrary precision of viscous stress and heat fluxes on irregular unstructured grids, while the FV method could only realize the first-order accuracy of the heat fluxes at the boundary faces and may exhibit erroneous behaviors. It also demonstrated that the high-order accuracy of gradients was needed to decrease errors of heat fluxes and viscous stresses, and that DG method was a promising method.
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Weber, Anton, Christian Morsbach, Edmund Kügeler, Christoph Rube, and Matthias Wedeking. "Flow Analysis of a High Flowrate Centrifugal Compressor Stage and Comparison With Test Rig Data." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-56551.
Full textAbstract:
The flow field inside a single-stage centrifugal compressor characterized by a high flowrate of Φ = 0.15 and a design total pressure ratio of approximately 1.4 is analysed numerically. The stage geometry consists of a radially oriented inlet duct with uniform inflow without swirl, a 90 deg inlet bend in front of the impeller, the shrouded impeller itself followed by a large radial vaneless diffuser, a 180 deg U-turn, a radially oriented turning vane, a subsequent 90 deg bend, and as the last item a long axial exit duct. The impeller blades have large fillets at hub and tip and thick blunt trailing edges. Due to the rotating shroud, a labyrinth seal is placed above the impeller with 5 seal tips. The complete leakage region is also included in the CFD analysis. The blade numbers for the impeller and vane are 15 and 14, respectively. The test rig has recently been built at the Institute of Propulsion and Turbomachinery at RWTH Aachen University (Germany). The first part of the CFD work presented was carried out before the first experimental data were available. Using the k-ω turbulence model of Wilcox (1988), a number of principal steady RANS calculations were performed to investigate the following: Impact of near wall grid resolution and turbulence model wall boundary condition treatment, impact of impeller fillets, and the influence of leakage flow. This part is completed by a comparison of steady RANS simulations with the time-mean results of unsteady RANS analyses of one blade passage. For the calculations presented in the second part, experimental data are available at the inflow and outflow planes. At these planes overall mean values were deduced. Additionally, 3- and 5-hole probe data are available at spanwise traverse planes located at the zenith of the U-turn and in the exit plane. For part two a finer grid with y+ values of approximately unity for all solid walls was used. In addition to the Wilcox k-ω model and the Menter SST k-ω model, two higher level turbulence models — the explicit algebraic Reynolds stress model Hellsten EARSM k-ω and the differential Reynolds stress model SSG/LRR-ω — have been tested and compared with the experiments. The agreement in terms of overall performance (total pressure ratio, isentropic efficiency) is satisfactory for all turbulence models used, but there are some differences: the k-ω model is shown to be the most stable one towards stall. On the other hand, it is shown that details of the flow field in terms of the two spanwise traverses can be better represented by the more advanced turbulence models. All CFD simulations have been performed at 100% shaft speed.
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Jonsson, Isak, Srikanth Deshpande, Valery Chernoray, Oskar Thulin, and Jonas Larsson. "Experimental and Numerical Study of Laminar-Turbulent Transition on a Low-Pressure Turbine Outlet Guide Vane." In ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/gt2020-14990.
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Abstract This work presents an experimental and numerical investigation on the laminar-turbulent transition and secondary flow structures in a Turbine Rear Structure (TRS). The study was executed at engine representative Reynolds number and inlet conditions at three different turbine load cases. Experiments were performed in an annular rotating rig with a shrouded low-pressure turbine upstream of a TRS test section. The numerical results were obtained using the SST k–ω turbulence model and the Langtry-Menter γ–θ transition model. The boundary layer transition location at the entire vane suction side is investigated. The location of the onset and the transition length are measured using IR-thermography along the entire vane span. The IR-thermography approach was validated using hot-wire boundary layer measurements. Both experiments and CFD show large variations of transition location along the vane span with strong influences from endwalls and turbine outlet conditions. Both correlate well with traditional transition onset correlations near midspan and show that the transition onset Reynolds number is independent of the acceleration parameter. However, CFD tends to predict an early transition onset in the midspan vane region and a late transition in the hub region. Furthermore, in the hub region, CFD is shown to overpredict the transverse flow and related losses.
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Da Soghe, Riccardo, Luca Innocenti, Antonio Andreini, and Se´bastien Poncet. "Numerical Benchmark of Turbulence Modeling in Gas Turbine Rotor-Stator System." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22627.
Full textAbstract:
Accurate design of the secondary air system is one of the main tasks for reliability and performance of gas turbine engines. The selection of a suitable turbulence model for the study of rotor-stator cavity flows, which remains an open issue in the literature, is here addressed for several operating conditions. A numerical benchmark of turbulence models is indeed proposed in the case of rotor-stator disk flows with and without superimposed throughflow. The predictions obtained by the means of several two equation turbulence models available within the CFD solver Ansys CFX 12.0 are compared with those previously evaluated by Poncet et al. (1; 2) through the Reynolds Stress Model (RSM) of Elena and Schiestel (3; 4) implemented in a proprietary finite volume code. The standard k-ε and k-ω SST models including high and low Reynolds approaches, have been used for all calculations presented here. Furthermore, some tests were performed using the innovative k-ω SST-CC and k-ω SST-RM models that take into account the curvature effects via the Spalart-Shur correction term (5) and the reattachement modification proposed by Menter (6) respectively. The numerical calculations have been compared to extensive velocity and pressure measurements performed on the test rig of the IRPHE’s laboratory in Marseilles (1; 2). Several configurations, covering a large range of real engine operating conditions, were considered. The influence of the typical non dimensional flow parameters (Reynolds number and flowrate coefficient) on the flow structure is studied in detail. In the case of an enclosed cavity, the flow exhibits a Batchelor-like structure with two turbulent boundary layers separated by a laminar rotating core. When an inward axial throughflow is superimposed, the flow remains of Batchelor type with a core rotating faster than the disk because of conservation of the angular momentum. In this case, turbulence intensities are mainly confined close to the stator. Turbulence models based on a low Reynolds approach provide better overall results for the mean and turbulent fields especially within the very thin boundary layers. The standard k-ω SST model offers the best trade-off between accuracy and computational cost for the parameters considered here. In the case of an outward throughflow, the k-ω SST in conjunction with a low Reynolds approach and RSM models provide similar results and predict quite well the transition from the Batchelor to the Stewartson structures.