Graphic summary
  • Show / hide key
  • Information


Scientific and technological production
  •  

1 to 50 of 147 results
  • Combining vibrational linear-by-part dynamics and kinetic-based decoupling of the dynamics for multiple smooth impacts with redundancy

     Barjau Condomines, Ana; Agullo Batlle, Joaquim; Font Llagunes, Josep Maria
    Multibody system dynamics
    Date of publication: 2014-04
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    This article proposes a simple linear-by-part approach for perfectly elastic 3D multiple-point impacts in multibody systems with perfect constraints and no friction, applicable both to nonredundant and redundant cases (where the normal velocities of the contact points are not independent). The approach is based on a vibrational dynamical model, and uses the so called ¿independent contact space.¿ Two different time and space scales are used. At the macroscale, the impact interval is negligible, and the overall system configuration is assumed to be constant. Consequently, the inertia and Jacobian matrices appearing in the formulation are also constant. The dynamics at the contact points is simulated through stiff springs undergoing very small deformations and generating system vibrations at the microscale.

  • Formulation to predict lower limb muscle forces during gait

     Serrancoli Masferrer, Gil; Walter, J.P.; Kinney, A.L.; Barjau Condomines, Ana; Fregly, Benjamin J.; Font Llagunes, Josep Maria
    Reunión del Capítulo Español de la Sociedad Europea de Biomecánica
    Presentation's date: 2013-10-24
    Presentation of work at congresses

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Access to the full text
    A linear-by-part approach for dissipative multiple-point collisions in smooth multibody systems with perfect constraints  Open access

     Barjau Condomines, Ana; Agullo Batlle, Joaquim; Font Llagunes, Josep Maria
    Joint International Conference on Multibody System Dynamics
    Presentation's date: 2012-05-30
    Presentation of work at congresses

    Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

  • Dynamic analysis of impact in swing-through crutch gait using impulsive and continuous contact models

     Font Llagunes, Josep Maria; Barjau Condomines, Ana; Pamies Vila, Rosa; Kövecses, József
    Multibody system dynamics
    Date of publication: 2012-09-01
    Journal article

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    The dynamics associated with the impact of the crutch with the ground is an important topic of research, since this is known to be the main cause of mechanical energy loss during swing-through gait. In this work, a multibody system representing a subject walking with crutches is used to investigate the behavior of two different contact models, impulsive and continuous, used for impact analysis. In the impulsive (discrete) approach, the impact interval is considered to be negligible and, therefore, the system configuration is constant. The postimpact state is directly obtained from the preimpact one through algebraic equations. In the continuous approach, the stiffness and dissipation characteristics of the contact surfaces are modeled through nonlinear springs and dampers. The equations of motion are integrated during the impact time interval to obtain the postimpact state, which, in principle, can differ from that obtained by means of the impulsive approach. Although both approaches have been widely used in the field of biomechanics, we have not found any comparative study in the existing literature justifying the model chosen for impact analysis. In this work, we present detailed numerical results and discussions to investigate several dynamic and energetic features associated with crutch impact. Based on the results, we compare the implications of using one contact model or the other.

  • Biomechanical study of intervertebral disc degeneration  Open access

     González Gutiérrez, Ramiro Arturo
    Defense's date: 2012-01-09
    Department of Mechanical Engineering, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    Degeneration and age affect the biomechanics of the intervertebral disc, by reducing its stiffness, flexibility and shock absorption capacities against daily movement and spinal load. The biomechanical characterization of intervertebral discs is achieved by conducting mechanical testing to vertebra-disc-vertebra segments and applying axial, shear, bend and torsion loads, statically or dynamically, with load magnitudes corresponding to the physiological range. However, traditional testing does not give a view of the load and deformation states of the disc components: nucleus pulposus, annulus fibrosus and endplate. Thus, the internal state of stress and strains of the disc can only be predicted by numerical methods, one of which is the finite element method. The objective of this thesis was, to study the biomechanics of degenerated intervertebral discs to load conditions in compression, bending and torsion, by using mechanical testing and a finite element model of disc degeneration, based on magnetic resonance imaging (MRI). Therefore, lumbar discs obtained from cadavers corresponding to spinal levels L2-L3 and L4-L5 with mild to severe degeneration were used. Intervertebral osteochondrosis and spondylosis deformans were identified, being the disc space collapse, the most striking feature. Next, all discs were tested to static and dynamic load conditions, the results gained corresponded to the disc stiffness (in compression, bending and torsion), stress relaxation and dynamic response. Of these, the stiffness response was used to validate the disc model. The testing results suggest that discs with advanced degeneration over discs with mild degeneration are, less rigid in compression, less stiffer under bending and torsion, showed less radial bulge, and reduce their viscoelastic and damping properties. This study shows that degeneration has an impact on the disc biomechanical properties which can jeopardize normal functionality. Development of one finite element model of disc degeneration started by choosing a MRI of a L2-L3 disc. Segmentation of vertebra bone and disc materials followed, and were based on pixel brightness and radiology fundamentals, then a finite element mesh was created to account for the disc irregular shape. The disc materials were modeled as hyperelastic and the bone materials were modeled as orthotropic and isotropic. Adjustment of material properties was based on integrity of the annulus fibrosus, giving a stiffness value matching that of a mild degeneration disc. Then, validation of the model was performed, and included a study of the distributions of stress and strain under loads of compression, bending and torsion. The results from all load simulations show that the disc undergoes large deformations. In contrast, the vertebrae are subjected to higher stress but with negligible deformations. In compression, the model predicted formation of symmetrical disc bulge which agree with the testing behavior. The nucleus pulposus showed to be the principal load carrier with negative principal stresses and strains. In bending and torsion, the annulus fibrosus showed to be the principal load carrier with large symmetrical principal strains and stresses for the former loading and large shearing for the latter. The study showed the importance of soft tissue deformation, mostly noticed in advanced degeneration. In contrast, the higher stresses in the vertebra over those of the intervertebral disc showed the relevance of bone predisposition to fracture. Such kind of studies, should contribute to the understanding of the biomechanics of the intervertebral disc.

    La degeneración y edad afectan la biomecánica del disco intervertebral, reduciendo la capacidad de rigidez, flexibilidad y atenuación de impactos, contra el movimiento y carga del raquis. La caracterización biomecánica del disco se realiza con ensayos mecánicos a segmentos de vértebra-disco-vértebra y aplicando cargas axiales, cortantes, flexión y torsión, estáticas ó dinámicas, con magnitudes de carga según el intervalo fisiológico. Sin embargo, las pruebas tradicionales no dan una visión de los estados de carga y deformación de los componentes del disco: núcleo pulposo, anillo fibroso y placa terminal. Por lo tanto, el estado interno de esfuerzos y deformaciones del disco, solo puede ser predicho con métodos numéricos, uno de los cuales es el método de elemento finito. El objetivo de esta tesis fue, estudiar la biomecánica de discos intervertebrales degenerados a las condiciones de carga en compresión, flexión y torsión, mediante el uso de ensayos mecánicos y de un modelo de elementos finitos de la degeneración de disco, basado en imágenes con resonancia magnética (MRI). Por lo tanto, se usaron discos lumbares L2-L3 y L4-L5 obtenidos de cadáveres, con degeneración leve a severa. Se identificó osteocondrosis intervertebral y espondilosis deformante, siendo el colapso del espacio intervertebral el aspecto más relevante. Luego, todos los discos fueron ensayados a condiciones de carga estática y dinámica, y los resultados correspondieron a la rigidez del disco (a compresión, flexión y torsión), a la relajación de tensiones y a la respuesta dinámica. De éstos, la rigidez fue usada para validar el modelo de disco. Los resultados de los ensayos sugieren que los discos con degeneración avanzada sobre aquellos con degeneración leve son, menos rigidos a compresión, menos rigidos a flexión y torsión, presentan menor protuberancia radial, y reducen sus propiedades viscoelásticas y de amortiguamiento. El estudio muestra que la degeneración impacta las propiedades biomecánicas del disco, poniendo en riesgo la funcionalidad normal. El desarollo de un modelo de elementos finitos de la degeneración de disco inició eligiendo una secuencia de resonancia magnética de un disco L2-L3. La segmentación de los materiales del disco y de las vértebras se realizó basado en intensidad de brillo del pixel y en fundamentos de radiología, y se creó una malla de elementos finitos correspondiente a la forma irregular del disco. Los materiales del disco se modelaron como hiperelásticos y los tejidos óseos se modelaron como materiales ortotrópicos e isotrópicos. El ajuste de propiedades de los materiales fue basado en la integridad del anillo fibroso, y dio una rigidez correspondiente a la de un disco con degeneración leve. Luego, se realizó la validación del modelo, e incluyó un estudio de las distribuciones de esfuerzo y deformación a las condiciones de carga en compresión, flexión y torsión. Los resultados de todas las simulaciones de carga mostraron que el disco es sometido a grandes deformaciones. En contraste, las vértebras fueron sometidas a mayores esfuerzos pero con deformaciones insignificantes. En compresión, el modelo predijo la formación de una protuberancia radial simétrica, en concordancia con la experimentación. El núcleo pulposo mostró ser el portador principal de carga, con tensiones y deformaciones principales negativas. En flexión y torsión, el anillo fibroso mostró ser el portador principal de carga, con grandes deformaciones y tensiones principales simétricas para la primera carga, y con grandes tensiones cortantes para la segunda carga. El estudio mostró la importancia de las deformaciones de los tejidos blandos, principalmente notados en la degeneración avanzada. Por el contrario, las tensiones mayores en los cuerpos vertebrales sobre aquellas del disco intervertebral mostraron la relevancia de la predisposición a las fracturas óseas. Este tipo de estudio debe contribuir a la comprensión de la biomecánica del disco intervertebral.

  • Access to the full text
    A linear approach for multiple-point impact in multibody systems  Open access

     Agullo Batlle, Joaquim; Barjau Condomines, Ana; Font Llagunes, Josep Maria
    European Congress on Computational Methods in Applied Sciences and Engineering
    Presentation's date: 2011-07-06
    Presentation of work at congresses

    Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

  • Two approaches for the dynamic analysis of impact in biomechanical systems

     Font Llagunes, Josep Maria; Barjau Condomines, Ana; Pamies Vila, Rosa; Kövecses, József
    Symposium on Brain, Body and Machine
    Presentation's date: 2010-11-11
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Two main approaches are used when studying impact problems involving rigid bodies: impulsive and compliant. In an impulsive approach, the impact time interval is considered to be negligible, and so the system configuration is assumed to be constant. The final mechanical state can be obtained directly from the initial one by means of algebraic equations and energy dissipation assumptions. In a compliant approach, the colliding surfaces are modeled through nonlinear springs and dampers, and the differential equations of motion are integrated to solve the forward dynamics. In this paper, the performance of the two approaches is compared in two biomechanical application examples.

  • Comparison of impulsive and compliant contact models for impact analysis in biomechanical multibody systems

     Font Llagunes, Josep Maria; Kövecses, József; Pamies Vila, Rosa; Barjau Condomines, Ana
    International Conference on Multibody System Dynamics
    Presentation's date: 2010-05-25
    Presentation of work at congresses

    Read the abstract Read the abstract View View Open in new window  Share Reference managers Reference managers Open in new window

    Two approaches are used when studying impact problems: impulsive ones and compliant ones. In an impulsive approach, the time interval where the collision takes place is considered to be negligible, and so the system configuration is assumed to be constant. The final mechanical state of the colliding system is obtained directly from the initial one through algebraic equations and energy dissipation assumptions. In a compliant approach, the colliding surfaces are modelled through springs and dampers (usually nonlinear), and the equations of motion are integrated during the impact time interval to obtain the final state. Though both approaches have been widely used in the field of biomechanics, no comparative study can be found in the literature that could justify choosing one or another. In this paper, we present both approaches and compare them when applied to two examples related to gait problems: a passive walker and a simple model of crutch locomotion. We will show that the results are really close whenever nonsliding conditions are assumed at the impact points.

  • Calibration for mobile robots with an invariant Jacobian

     Agullo Batlle, Joaquim; Font Llagunes, Josep Maria; Barjau Condomines, Ana
    Robotics and autonomous systems
    Date of publication: 2010-01
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • APLICACIÓN DE TÉCNICAS DE DINÁMICA MULTICUERPO AL DISEÑO DE ORTESIS ACTIVAS PARA LA AYUDA A LA MARCHA

     Pamies Vila, Rosa; Barjau Condomines, Ana; Agullo Batlle, Joaquim; Serrancoli Masferrer, Gil; Font Llagunes, Josep Maria
    Participation in a competitive project

     Share

  • Holonomy in mobile robots

     Agullo Batlle, Joaquim; Barjau Condomines, Ana
    Robotics and autonomous systems
    Date of publication: 2009-04
    Journal article

     Share Reference managers Reference managers Open in new window

  • Optimal design of a tenora

     Agullo Batlle, Joaquim; Barjau Condomines, Ana
    International Symposium on Musical Acoustics
    Presentation's date: 2007-07
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • On the one-dimensional acoustic propagation in conical ducts with stationary mean flow

     Barjau Condomines, Ana
    Journal of the Acoustical Society of America
    Date of publication: 2007-12
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Calculation of impulse responses with a cellular automata algorithm

     Barjau Condomines, Ana
    147th meeting of the Acoustical Society of America
    Presentation's date: 2004-05-25
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Exploring a Van der Pol woodwind

     Barjau Condomines, Ana
    147th meeting of the Acoustical Society of America
    Presentation's date: 2004-05-25
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Conceptes d'acústica musical

     Barjau Condomines, Ana
    Date of publication: 2003-06-30
    Book chapter

     Share Reference managers Reference managers Open in new window

  • Les instruments à vent Renaissance de la cathédrale de Salamanque

     Barjau Condomines, Ana
    Date of publication: 2003-02-28
    Book chapter

     Share Reference managers Reference managers Open in new window

  • Acoustical propagation in a prefractal waveguide

     Vincent, Gibiat; Barjau Condomines, Ana; Kaelig, Castor; Etienne, Bertaud Du Chazaud
    Physical review E, statistical physics, plasmas, fluids, and related interdisciplinary topics
    Date of publication: 2003-06
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Delayed models for simplified musical instruments

     Barjau Condomines, Ana; Vincent, Gibiat
    Journal of the Acoustical Society of America
    Date of publication: 2003-07
    Journal article

    View View Open in new window  Share Reference managers Reference managers Open in new window

  • Unified modelling of simplified musical instruments in time domain

     Barjau Condomines, Ana; Gibiat, V; Chareyron, D
    FORUM ACUSTICUM Sevilla 2002. 3rd. European Congress on Acoustics XXXIII SPANISH CONGRESS ON ACOUSTICS-Tecniacústica 2002
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Un témoignage historique, musicologique et acoustique: les hautbois de la cathédrale de Salamanque.

     Barjau Condomines, Ana
    Colloque International "Les hautbois populaires en France et dans la Méditerranée"
    Presentation's date: 2002-04-06
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • L'archet du violon: une non-linéarité et une discontinuité dans un système à retards multiples

     Barjau Condomines, Ana
    6ème Congrès Français d'Acoustique
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • The acoustical impedance or how to guess the sound of a silent instrument

     Barjau Condomines, Ana
    International Symposium on Musical Acoustics
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • The acoustical impedance or how ti guess the sound of a silent instrument

     Barjau Condomines, Ana
    International Symposium on Musical Acoustics
    Presentation's date: 2002-12-09
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Ware propagation in self-similar structures

     Barjau Condomines, Ana
    FORUM ACUSTICUM Sevilla 2002. 3rd. European Congress on Acoustics XXXIII SPANISH CONGRESS ON ACOUSTICS-Tecniacústica 2002
    Presentation's date: 2002-09-19
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Ware propagation in self-similar structures

     Bertrand, Du Chazand E; Gibiat, V; Barjau Condomines, Ana
    FORUM ACUSTICUM Sevilla 2002. 3rd. European Congress on Acoustics XXXIII SPANISH CONGRESS ON ACOUSTICS-Tecniacústica 2002
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • L'archet du vidon: une non-linéarité et une discontinuité dans un système à retards multiples

     Barjau Condomines, Ana
    6ème Congrès Français d'Acoustique
    Presentation's date: 2002-04-08
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Delay lines, finite differences and cellular automata: three close but different schemes for simulating acoustical propagation in 1D systems

     Barjau Condomines, Ana; Gibiat, V
    Acustica united with acta acustica
    Date of publication: 2002-05
    Journal article

     Share Reference managers Reference managers Open in new window

  • Modèle hybride réduit pour la corde frottée

     Barjau Condomines, Ana
    "Instruments à corde: entre facture, acoustique et musique"
    Presentation's date: 2001-04-20
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Conceptes d'acústica musical

     Barjau Condomines, Ana
    Date of publication: 2001-12-31
    Book chapter

     Share Reference managers Reference managers Open in new window

  • Phenomenological models for musical instruments

     Barjau Condomines, Ana
    17th International Congress on Acoustics
    Presentation's date: 2001-09-03
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Phenomenological models for musical instruments

     Barjau Condomines, Ana; Vincent, Gibiat
    17th International Congress on Acoustics
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Simulación de los procesos de lacado plastificado y vendado de perfiles de aluminio.

     Santos Lopez, M. Antonia de Los; Barjau Condomines, Ana; Ferrer Marti, Laia
    Date: 2001-06
    Report

     Share Reference managers Reference managers Open in new window

  • Phenomenological models for musical instruments

     Barjau Condomines, Ana; Vincent, Gibiat
    Rivista italiana di acustica
    Date of publication: 2001-09
    Journal article

     Share Reference managers Reference managers Open in new window

  • Copie et tradition dans les chalemies: de la Renaissance aux instruments populaires du XXème siècle

     Barjau Condomines, Ana
    Fabrication artisanale d'instruments de musique: procédés, acoustique et perspectives
    Presentation's date: 2000-06-09
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • A study of shawms: from the ancestors of the Renaissance to the survivors of the 20th century

     Barjau Condomines, Ana
    The Physics Congress
    Presentation's date: 2000-03-27
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window

  • Acoustic propagation in flaring, axisymmetric horns: I. A new family of unidimensional solutions

     Agullo Batlle, Joaquim; Barjau Condomines, Ana; Keefe, Douglas H.
    Acustica
    Date of publication: 1999-06
    Journal article

     Share Reference managers Reference managers Open in new window

  • Acoustic propagation in flaring, axisymmetric horns: I. A new family of unidimensional solutions

     Agullo Batlle, Joaquim; Barjau Condomines, Ana; Douglas, Keefe H
    Acustica united with acta acustica
    Date of publication: 1999-03
    Journal article

     Share Reference managers Reference managers Open in new window

  • Contribució a l'estudi de l'acústica dels tubs axisimètrics  Open access

     Jordi Nebot, Lluïsa
    Defense's date: 1999-10-14
    Department of Mechanical Engineering, Universitat Politècnica de Catalunya
    Theses

    Read the abstract Read the abstract Access to the full text Access to the full text Open in new window  Share Reference managers Reference managers Open in new window

    La tesi "Contribució a l'estudi de l'acústica dels tubs axisimètrics" és un treball centrat en l'estudi del comportament acústic dels tubs dels instruments musicals de vent amb simetria de revolució en el qual es fa especial èmfasi en el comportament del pavelló (tub axisimètric de conicitat variable).L'estudi contempla tres aspectes: l'analític, el numèric i l' experimental, necessari per poder comparar els models proposats però que no ha estat realizat per l'autora de la tesi. Quant a l'estudi analític, s'analitza en profunditat el model uniparamètric proposat per Webster al qual se li han trobat els límits d'aplicabilitat, per al cas dels pavellons de tenores (instrument típic català), i es realitza una extensió d'aquest model en passar-lo al domini temporal.Seguint dins de l'estudi analític, s'estableix un model temporal bidimensional aproximat que inclou la propagació a l'interior de les lentilles presents a les discontinuïtats de conicitat i que simula, en primera aproximació, l'efecte dispersiu que es produeix en la propagació a l'interior dels pavellons.Quant al tractament numèric, es realitza un estudi d'un altre model uniparamètric existent, l'equació "Conical Horn", que s'aplica a un pavelló amb perfil exponencial. La comparació dels resultats experimentals amb els del model permet establir-ne la bondat. Seguint dins del tractament numèric, s'estableix un primer model bidimensional basat en la propagació de raigs impulsionals que permet l'obtenció del camp acústic a l'interior dels tubs axisimètrics.Per altra banda, s'estableix un algoritme de càlcul per a la integral de convolució que permet simular de manera completa el comportament d'un instrument musical en el domini temporal.

    La tesis "Contribució a l'estudi de l'acústica dels tubs axisimètrics" es un trabajo centrado en el estudio del comportamiento acústico de los tubos de los instrumentos musicales de viento con simetría de revolución en el que se hace especial énfasis al comportamiento del pabellón (tubo axisimétrico de conicidad variable).El estudio contempla tres aspectos: el analítico, el numérico y el experimental, necesario para poder comparar los modelos propuestos pero que no se ha realizado por la autora de la tesis.En cuanto al estudio analítico, se analiza en profundidad el modelo uniparamétrico propuesto por Webster al que se le han encontrado sus límites de aplicabilidad, para el caso de los pabellones de "tenoras" (instrumento típico catalán), y se realiza una extensión de este modelo al pasarlo al dominio temporal.Siguiendo dentro del estudio analítico, se establece un modelo temporal bidimensional aproximado que incluye la propagación en el interior de las lentillas presentes en las discontinuidades de conicidad y que simula en primera aproximación el efecto dispersivo que se produce en la propagación en el interior de los pabellones.En cuanto al tratamiento numérico, se realiza un estudio de otro modelo uniparamétrico existente, la ecuación "Conical Horn", que se aplica a un pabellón con perfil exponencial. La comparación de los resultados experimentales con los del modelo permiten establecer la bondad de éste.Siguiendo dentro del tratamiento numérico, se establece un primer modelo bidimensional basado en la propagación de rayos impulsionales que permite la obtención del campo acústico en el interior de los tubos axisimétricos.Por otro lado, se establece un algoritmo de cálculo para la integral de convolución que permite simular de manera completa el comportamiento de un instrumento musical en el dominio temporal.

    The doctoral thesis named "Contribució a l'estudi de l'acústica dels tubs axisimètrics" is a research project focused in the study of the acoustical behaviour of the musical wind instruments bores with revolute simmetry in which a special emphasis is done in the behaviour of the horn (axisymmetrical tube with varying taper).The study looks at three aspects: the analytical, the numerical an d the experimental one, necessary to compare the proposed models but which has not been done by the author of the thesis.With regard to the analytical study, the uniparametrical model proposed by Webster is deeply analyzed; its applicability limits has been found for the horns of "tenores" (Catalan tenor shawn, double-reed conical woodwind) and an extension of the model is done passing it to the time domain.Going on with the analytical study, an approximated bidimensional temporal model is stablished in which the propagation inside the little lents present in taper discontinuities is taken into account. This model permits to simulate, in a first approximation, the dispersive effect that takes place in the propagation inside the horns.As for the numerical treatment, a study about another uniparametrical actual model is done. It's the Conical horn equation which is applied to a horn with exponential profile.The comparison between the experimental results and those obtained with the model allows to stablish its validity.Keeping on the numerical treatment, a first bidimensional model is stablished based on the propagation of impulsional rays. It allows to obtain the acoustical field inside the axisymmetrical tubes.In other side, an algorithm to calculate the convolution integral is stablished. It permits to simulate completely the behaviour of a musical instrument in the time domain.

  • Propagación acústica en medios de geometría fractal

     Jordi Nebot, Lluïsa; Barjau Condomines, Ana
    Participation in a competitive project

     Share

  • Propagación acústica en medios de geometría fractal

     Barjau Condomines, Ana; Gibiat, Vincent
    Participation in a competitive project

     Share

  • Self-excitation in woodwinds: from a particular model to a generic model

     Barjau Condomines, Ana
    Forum Acusticum 1999
    Presentation's date: 1999-03-14
    Presentation of work at congresses

     Share Reference managers Reference managers Open in new window