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Vertical axis wind turbine performance prediction: a new approach to the double multiple streamtube model

Melício, Rui; Batista, N.C.; Matias, J.C.O.; Catalão, J.P.S.
Fonte: International Conference on Renewable Energies and Power Quality — ICREPQ´12 Publicador: International Conference on Renewable Energies and Power Quality — ICREPQ´12
Tipo: Aula
POR
Relevância na Pesquisa
106.24%
The vertical axis wind turbines (VAWT) have been suffering an increased acceptance for urban wind turbines integration in the future smart grid for decentralized generation (DG). The VAWT have several advantages over the more conventional horizontal axis wind turbines (HAWT): the smaller number of components; low sound emissions; their insensitivity to fast changes in wind flow direction; a lower architectural visual impact; the ability to operate closer to the ground; and others. But, the VAWT aerodynamic performance is more complex to simulate and predict due to its three dimensional operation. Several mathematical models have been presented to predict the VAWT performance, such as the double multiple streamtube (DMS) model. With the aim of presenting a tool to ease the study of complex shaped VAWTs, being at the same time able to be easily integrated in computational design tools, a new approach to the DMS model is presented in this paper.

Desempeño aerodinámico de turbinas eólicas de eje vertical en función de temperatura de superficie de álabe

Thomaz Junior, Celso Rangel
Fonte: Universidad de Chile Publicador: Universidad de Chile
Tipo: Tesis
ES
Relevância na Pesquisa
45.84%
Magíster en Ingeniería Civil Mecánica; Ingeniero Civil Mecánico; Este estudio presenta simulaciones numéricas de una turbina eólica de eje vertical (VAWT) tipo Darrieus utilizando técnicas de control de flujo pasivo, específicamente variando las temperaturas de superficie de álabe, con el objetivo de determinar si es posible obtener un mejor desempeño aerodinámico de la turbina. El gradiente de temperatura entre el álabe y el flujo puede generar atrasos o adelantos en el desprendimiento de la capa límite, y variaciones en la frecuencia de desprendimiento de vórtices. Luego, se pueden utilizar estas técnicas para reducir o aumentar fuerzas aerodinámicas donde sea favorable. Las simulaciones son realizadas con el método de volúmenes finitos utilizando un software comercial (ANSYS Fluent 13.0.0), con el modelo de turbulencia k-omega SST. Se utiliza un modelo bidimensional rotor-estator transiente, usando una malla deslizante, para así capturar los cambios en el flujo a través de la rotación. También se utiliza el Double-Multiple Streamtube Model (DMST) como método de validación numérica. Como resultados, se obtienen incrementos en el torque y potencia media de la turbina al enfriarla uniformemente, mientras que se obtienen caídas de torque y potencia media al calentarla uniformemente. Estos resultados se explican a través de la relación entre fuerzas aerodinámicas con las propiedades físicas...

On a self-start Darrieus wind turbine: blade design and field tests

Melicio, Rui
Fonte: Renewable and Sustainable Energy Reviews (ELSEVIER) Publicador: Renewable and Sustainable Energy Reviews (ELSEVIER)
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
45.84%
This paper is about a design of an urban area Darrieus VAWT, having self-start ability due to an innovative profile design named EN0005, avoiding the need of extra components or external electricity feed-in. An approach is presented to study the ability of a blade profile to offer self-start ability. Methodologies applied for the blade body and for profile development are reported. Field tests and main conclusions are presented to persuade for the arrangement of this design.

Innovative design on technology of urban Darrieus VAWT: field tests

Melicio, Rui
Fonte: 16th IEEE International Conference on Computer as a Tool — EUROCON 2015 Publicador: 16th IEEE International Conference on Computer as a Tool — EUROCON 2015
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
45.87%
This paper is about an innovative design for an urban Darrieus Vertical Axis Wind Turbine (VAWT), having the ability of having self-start at low wind velocities, but without the need for extra components or external electricity feed-in. A new mathematical model to assess complex shaped Darrieus VAWT prototype is presented in this paper and offers a new approach to the Double Multiple Streamtube model. Field tests to assess the behavior of the prototype and main conclusions are presented.