Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Velocity distribution of wall-attached jets in slotted-inlet ventilated rooms
https://orcid.org/0000-0002-9461-3793
Abstract The wall-attached jets for ventilation in spaces have been drawn considerable interest for their benefit of high ventilation efficiency and thermal sensation. In this study, the velocity distribution of a wall-attached jet under isothermal conditions in slotted-inlet ventilated spaces is investigated by experimental and numerical approaches. The wall-attached jet issues air from a slot inlet that flows down along the surface of a vertical wall, impinging on the floor attached to the vertical wall and spreading over the floor surface. The results show that the flow field of a wall-attached jet can be divided into three regions: vertical attachment region (region I), horizontal air reservoir region (region II), and jet impingement region. The correlation equations for the centerline velocity decay and velocity profiles are obtained. For the fully developed jet in region I and II, the dimensionless velocity profiles can be expressed as u 0/u m(y*)~(y*/b)γ and u 0/u m(x)~(x/b + K h)γ, respectively, where γ is a constant related to the momentum decay rate. Over the whole range of jet flow conditions in this study, the value of γ is 1.11. Moreover, a unified exponential expression for the cross-sectional velocity profiles is proposed for both regions I and II. For the jet impingement region, the flow is complex and involves separation, reattachment, vortical flow, and pressure gradients. Large-scale vortices exist in the corner, and the vortices diminish as the jet inlet velocity increases. The current study can provide a theoretical basis for further engineering design applications of wall-attached jets for attachment ventilation.
Highlights The airflow characteristics of an isothermal wall-attached jet for attachment ventilation are investigated. Three flow regions are identified and analyzed. Correlation equations for centerline velocity decay and cross-sectional velocity profiles are derived. This study can provide a theoretical basis for further engineering design of attachment ventilation.
Velocity distribution of wall-attached jets in slotted-inlet ventilated rooms
https://orcid.org/0000-0002-9461-3793
Abstract The wall-attached jets for ventilation in spaces have been drawn considerable interest for their benefit of high ventilation efficiency and thermal sensation. In this study, the velocity distribution of a wall-attached jet under isothermal conditions in slotted-inlet ventilated spaces is investigated by experimental and numerical approaches. The wall-attached jet issues air from a slot inlet that flows down along the surface of a vertical wall, impinging on the floor attached to the vertical wall and spreading over the floor surface. The results show that the flow field of a wall-attached jet can be divided into three regions: vertical attachment region (region I), horizontal air reservoir region (region II), and jet impingement region. The correlation equations for the centerline velocity decay and velocity profiles are obtained. For the fully developed jet in region I and II, the dimensionless velocity profiles can be expressed as u 0/u m(y*)~(y*/b)γ and u 0/u m(x)~(x/b + K h)γ, respectively, where γ is a constant related to the momentum decay rate. Over the whole range of jet flow conditions in this study, the value of γ is 1.11. Moreover, a unified exponential expression for the cross-sectional velocity profiles is proposed for both regions I and II. For the jet impingement region, the flow is complex and involves separation, reattachment, vortical flow, and pressure gradients. Large-scale vortices exist in the corner, and the vortices diminish as the jet inlet velocity increases. The current study can provide a theoretical basis for further engineering design applications of wall-attached jets for attachment ventilation.
Highlights The airflow characteristics of an isothermal wall-attached jet for attachment ventilation are investigated. Three flow regions are identified and analyzed. Correlation equations for centerline velocity decay and cross-sectional velocity profiles are derived. This study can provide a theoretical basis for further engineering design of attachment ventilation.
Velocity distribution of wall-attached jets in slotted-inlet ventilated rooms
https://orcid.org/0000-0002-9461-3793
Abstract The wall-attached jets for ventilation in spaces have been drawn considerable interest for their benefit of high ventilation efficiency and thermal sensation. In this study, the velocity distribution of a wall-attached jet under isothermal conditions in slotted-inlet ventilated spaces is investigated by experimental and numerical approaches. The wall-attached jet issues air from a slot inlet that flows down along the surface of a vertical wall, impinging on the floor attached to the vertical wall and spreading over the floor surface. The results show that the flow field of a wall-attached jet can be divided into three regions: vertical attachment region (region I), horizontal air reservoir region (region II), and jet impingement region. The correlation equations for the centerline velocity decay and velocity profiles are obtained. For the fully developed jet in region I and II, the dimensionless velocity profiles can be expressed as u 0/u m(y*)~(y*/b)γ and u 0/u m(x)~(x/b + K h)γ, respectively, where γ is a constant related to the momentum decay rate. Over the whole range of jet flow conditions in this study, the value of γ is 1.11. Moreover, a unified exponential expression for the cross-sectional velocity profiles is proposed for both regions I and II. For the jet impingement region, the flow is complex and involves separation, reattachment, vortical flow, and pressure gradients. Large-scale vortices exist in the corner, and the vortices diminish as the jet inlet velocity increases. The current study can provide a theoretical basis for further engineering design applications of wall-attached jets for attachment ventilation.
Highlights The airflow characteristics of an isothermal wall-attached jet for attachment ventilation are investigated. Three flow regions are identified and analyzed. Correlation equations for centerline velocity decay and cross-sectional velocity profiles are derived. This study can provide a theoretical basis for further engineering design of attachment ventilation.
Velocity distribution of wall-attached jets in slotted-inlet ventilated rooms
Building and Environment ; 194
12.02.2021
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
Some Confinement Effects of Jets in Ventilated Rooms
| British Library Online Contents | 1998
Some Confinement Effects of Jets in Ventilated Rooms
| British Library Conference Proceedings | 1998
Turbulent flows in ventilated rooms
| TIBKAT | 1979
Deflection of wall-jets in ventilated enclosure described by pressure distribution
| Online Contents | 1999
Deflection of wall-jets in ventilated enclosure described by pressure distribution
| British Library Online Contents | 1999