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1	Size-Scale Effects of Nonlinear Weir Hydraulics Young, Nathan L. 01 May 2018 (has links) Experimental physical model studies of hydraulic structures are often conducted to replicate flow behavior that may occur at the prototype scale. Geometric similitude is most often maintained between the prototype and model when studying reservoir and open channel hydraulic structures to account for the dominant gravity and inertia forces while other fluid forces (e.g., viscosity,surface tension) are assumed negligible. However, as model size and/or upstream head decreases, other fluid forces can exceed the negligible level and influence model flow behavior. This phenomenon is referred to as size-scale effects and is one potential origin of error in predicting the prototype behavior through testing geometrically similar models. To extend the existing research of size-scale effects on nonlinear weirs half-and quarter-round trapezoidal labyrinth weirs and piano key weirs were fabricated at length ratios of 1, 2, 3, 6, and 12. The largest weir model for each weir type (i.e., a weir height of 36 in for labyrinth weir models and a weir height of 33 in for piano key weir models) served as the corresponding prototype.Weir models were hydraulically tested to assess differences among head-discharge relationships and flow behavior. Limiting criteria were recommended to avoid size-scale effects depending on the weir type and model size. The results of this study will help hydraulic modelers determine what limiting criteria should be met to avoid size-scale effects. Size Scale Effects Labyrinth Weir Piano Key Weir Head Discharge Nappe Civil and Environmental Engineering
2	Piano Key Weir Head Discharge Relationships Anderson, Ricky M. 01 May 2011 (has links) A piano key (PK) weir is a type of nonlinear (labyrinth-type) weir developed specifically for free-surface flow control structures with relatively small spillway footprints. Currently, no generally accepted standard PK weir design procedure is available. This is due, in part, to the large number of geometric parameters and a limited understanding of their effects on discharge efficiency (discharge efficiency is quantified by the discharge coefficient of the standard weir equation). However, Hydrocoop, a non-profit French dam spillways association, has recommended a PK weir design and a head-discharge relationship specific to that geometry. To develop a better understanding of the effects of PK weir geometry on discharge efficiency, 13 laboratory-scale, 4-cycle PK and rectangular labyrinth weir configurations were tested. As a result, the influence of the following PK weir geometries and/or modifications on discharge efficiency were partially isolated: the inlet-to-outlet key width ratio, upstream, and downstream apex overhangs; sloped floors; raising the crest elevation via a parapet wall; fillets underneath the upstream overhangs; and the crest type. The physical model test matrix also included a PK weir configuration consistent with the Hydrocoop-recommended design. From the experimental results, the appropriateness of the Hydrocoop-recommended head-discharge relationship was evaluated, along with the discharge coefficient behavior associated with the standard weir equation. Finally, trapezoidal labyrinth weirs were compared to PK weirs to make a relative comparison of nonlinear weir discharge efficiency; comparisons were made considering crest length and structure footprint. Labyrinth Weir Piano Key Weir PK Weir Weir Civil Engineering Engineering Water Resource Management
3	CFD Simulations of Flow Characteristics of a Piano Key Weir Spillway Sjösten, William, Vadling, Victor January 2020 (has links) Comprehensive rehabilitation projects of dam spillways are made in Sweden, due to stricter dam safety guidelines for their discharge capacity. The Piano Key Weir (PKW) is an innovative design which has proven effective through several renovation projects made in many countries including France. In this study we investigate the flow patterns around a prototype PKW, located in Escouloubre dam in southern France, with numerical simulations through three different flow cases in Ansys Fluent. A computational domain containing the PKW is created in the CAD software Ansys SpaceClaim for the simulations. Three polyhexcore meshes are further generated using Ansys Fluent Meshing. The three flow cases are then simulated with a Reynolds-averaged Navier-Stokes (RANS) model, coupled with realizable k-epsilon and volume of fluid models. Through an assessment of the discretization error between three meshes, a relative error of one percent is obtained for the discharge rate. The numerical results are qualitatively compared with results from previously conducted physical experiments on this PKW. The RANS model does not capture the water surface undulations (due to turbulence) around the PKW. The effects from under modelled surface undulations are alleviated by inserting an air vent to the PKW, which results in a flow behaviour in good agreement with the physical experiments. Through this alteration, water discharge rates are computed with a maximum discrepancy of five percent compared with the corresponding experimental values. A large eddy simulation should be conducted in the future, to bring further light on air exchange and water interaction phenomena present in the PKW flow pattern. Piano Key Weir Ansys Fluent Multiphase Flow Spillway Flow Characteristics CFD Realizable k-epsilon Volume of Fluid Renolds-averaged Navier-Stokes Engineering and Technology Teknik och teknologier
4	Assosiasie en koördinasie van notasie met klawers by die ontwikkeling van 'n leesvermoë by die klavierbeginner Hesse, Maria Elizabetha 30 November 2005 (has links) The study substantiates common strategies and theories regarding the teaching of sight-reading. The literature study done on sight-reading at the keyboard consists of opinions and recommendations resulting from empirical findings of well-known piano pedagogues. Seven beginner courses were analysed in order to assess their presentation of a well-structured development of piano sight-reading against the opinions and recommendations of well-known piano pedagogues and authors in this field as well as the personal experience of the researcher. During this process it was discovered that insufficient attention was paid to the development of the association between a note symbol and its corresponding key on the piano. However no attention was paid to the act of playing while reading ahead. The researcher compiled additional progressive exercises for the 7 to 9 year old beginner, to address the above-mentioned discrepancies. The exercises and their individual purposes are clearly explained with instructions regarding their performance. / Hierdie studie bevestig algemene strategieë en teorieë aangaande die ontwikkeling van vaardighede om musieknotasie te lees en te speel. Die literatuur wat in hierdie studie bestudeer is, handel oor opinies en aanbevelings van vooraanstaande klavierpedagoë wat voortspruit uit die resultate van hulle empiriese navorsing. Sewe aanvangskursusse is ontleed en die aktiwiteite en metodes waarvolgens vaardighede onderrig word om musieknotasie te leer lees en speel, is gemeet aan die aanbevelings van vooraanstaande klavierpedagoë, navorsers op die gebied, asook die navorser se eie ervaring met die boeke. Gedurende die studie is daar ontdek dat daar meesal nie aandag geskenk word aan die ontwikkeling van 'n assosiasie tussen 'n toonhoogtesimbool en ooreenstemmende klawer op die klavier nie en glad nie aan die proses van vooruitlees nie. Om hierdie tekortkominge te oorkom het die navorser 'n stel aanvullende en progressiewe oefeninge saamgestel wat maklik genoeg uitvoerbaar is vir die 7- tot 9-jarige beginner. Duidelike beskrywings van die oefeninge, elkeen se spesifieke doel, en aanwysings vir effektiewe uitvoering daarvan word verskaf. / Art History, Visual Arts & Music / M.A. (Musicology) Association Keyboard Beginner Look ahead Beginners course Melodic patterns Directional reading Piano key Ensemble playing Rhythmic patterns Exercises Sight-reading First lesson Topography Intervals Visualisation Aanvangskursusse Lees en speel Akkoordpatrone Melodiese patrone Assosiasie Oefeninge Beginner Ritmepatrone Eerste les Samespel Innerlike voorstelling Speelrigtings Interval-afstand Topografie Klavierklawer Vooruitlees Klawerbord 781.423071
5	Assosiasie en koördinasie van notasie met klawers by die ontwikkeling van 'n leesvermoë by die klavierbeginner Hesse, Maria Elizabetha 30 November 2005 (has links) The study substantiates common strategies and theories regarding the teaching of sight-reading. The literature study done on sight-reading at the keyboard consists of opinions and recommendations resulting from empirical findings of well-known piano pedagogues. Seven beginner courses were analysed in order to assess their presentation of a well-structured development of piano sight-reading against the opinions and recommendations of well-known piano pedagogues and authors in this field as well as the personal experience of the researcher. During this process it was discovered that insufficient attention was paid to the development of the association between a note symbol and its corresponding key on the piano. However no attention was paid to the act of playing while reading ahead. The researcher compiled additional progressive exercises for the 7 to 9 year old beginner, to address the above-mentioned discrepancies. The exercises and their individual purposes are clearly explained with instructions regarding their performance. / Hierdie studie bevestig algemene strategieë en teorieë aangaande die ontwikkeling van vaardighede om musieknotasie te lees en te speel. Die literatuur wat in hierdie studie bestudeer is, handel oor opinies en aanbevelings van vooraanstaande klavierpedagoë wat voortspruit uit die resultate van hulle empiriese navorsing. Sewe aanvangskursusse is ontleed en die aktiwiteite en metodes waarvolgens vaardighede onderrig word om musieknotasie te leer lees en speel, is gemeet aan die aanbevelings van vooraanstaande klavierpedagoë, navorsers op die gebied, asook die navorser se eie ervaring met die boeke. Gedurende die studie is daar ontdek dat daar meesal nie aandag geskenk word aan die ontwikkeling van 'n assosiasie tussen 'n toonhoogtesimbool en ooreenstemmende klawer op die klavier nie en glad nie aan die proses van vooruitlees nie. Om hierdie tekortkominge te oorkom het die navorser 'n stel aanvullende en progressiewe oefeninge saamgestel wat maklik genoeg uitvoerbaar is vir die 7- tot 9-jarige beginner. Duidelike beskrywings van die oefeninge, elkeen se spesifieke doel, en aanwysings vir effektiewe uitvoering daarvan word verskaf. / Art History, Visual Arts and Music / M.A. (Musicology) Association Keyboard Beginner Look ahead Beginners course Melodic patterns Directional reading Piano key Ensemble playing Rhythmic patterns Exercises Sight-reading First lesson Topography Intervals Visualisation Aanvangskursusse Lees en speel Akkoordpatrone Melodiese patrone Assosiasie Oefeninge Beginner Ritmepatrone Eerste les Samespel Innerlike voorstelling Speelrigtings Interval-afstand Topografie Klavierklawer Vooruitlees Klawerbord 781.423071

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