Numerical study of airflow and heat transfer in an air-cooled room with different inlet positions

Building energy simulations coupled with computational fluid dynamics tools have emerged, recently, as an accurate and effective tool to improve the estimation of energy requirements and thermal comfort in buildings. Building modelers and researchers usually implement this coupling in the boundary conditions of both tools (e.g. surface temperature, ambient temperature, and conductive and convective fluxes). This work reviews how the building energy simulation–computational fluid dynamics coupling has evolved since its first implementation to the present day. Moreover, this article also summarizes and discusses the research studies in which the building energy simulation–computational fluid dynamics coupling has been used to analyze building systems, building components, and building urban configurations. Implementing a building energy simulation–computational fluid dynamics coupling brings a series of benefits when compared with the conventional building energy simulation methodology, a building energy simulation–computational fluid dynamics coupling provides an improvement that ranges between 10% and 50% for estimating the building energy requirements. Moreover, the computation time to implement computational fluid dynamics with information obtained from the building energy simulation could be reduced by as well.

Section: Studies For Mechanical and Passive Systemsmentioning

confidence: 99%

Coupling building energy simulation and computational fluid dynamics: An overview

Rodríguez-Vázquez

Hernández-Pérez

Xamán

et al. 2020

“…The sensitivity study focused on the influence of model simplifications, finding that the following parameters strongly influence the timing, in order of significance: the location of inlet/outlet, window recess, and radiation. Rodrı´guez and Hinojosa (2014) presented 3D numerical results in a ventilated room considering three different inlet configurations. The study was carried out considering turbulent flow and the radiative exchange between the walls.…”

Section: Ventilated Cavities Without Heat Transfermentioning

confidence: 99%

“…Rodríguez and Hinojosa (2014) presented 3D numerical results in a ventilated room considering three different inlet configurations. The study was carried out considering turbulent flow and the radiative exchange between the walls.…”

Section: Introductionmentioning

confidence: 99%

Heat transfer and airflow study of turbulent mixed convection in a ventilated cavity

Hinojosa

Rodríguez

Xamán

2016

The experimental and numerical results of the heat transfer and airflow by turbulent mixed convection in a ventilated cavity are presented. The experimental setup was built to use air as the heat transfer fluid. One vertical wall receives a uniform and constant heat flux, whereas the opposite wall is maintained at constant temperature. The remaining walls are thermally insulated. The experimental temperature profiles were obtained for different heat fluxes and air inlet velocities. Five different turbulence models were used to obtain the numerical results. The comparison between experimental and numerical temperatures indicates that the standard k–ε turbulence model presents a better agreement, with maximum percentage differences between 2.0% and 3.0%. The heat transfer coefficient had values between 2.2 and 3.4 W/m2 K, and it increases with the Rayleigh number and the Reynolds number. The experimental and numerical convective heat transfer coefficient predictions are closer for the higher Reynolds number (inlet air velocity of 0.5 m/s). The effects of varying the Rayleigh and Reynolds number on flow patterns and temperature fields were analyzed numerically.

“…It has been concluded that a better thermal comfort condition and the ventilation performance can be achieved by locating the supply grills close to the centerline of the room while the location of the exhaust grills do not make any significant difference. Rodriguez and Hinojosa (2014) analyzed the the air flow in an aircooled rectangular room considering three different inlet configurations. They found that the radiative heat transfer is around 50%, and the heat transfer coefficients and temperature distribution effectiveness are highly dependent on the inlet position.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of laminar airflow heating, ventilation, and air conditioning system for particle dispersion control in operating room including staffs: A non-Boussinesq Lagrangian study

Amiraslanpour

Ghazanfarian

Nabaei

et al. 2020

Impacts of the laminar airflow ventilation system design factors on contaminant removal and thermal comfort condition in an operating room have been investigated by means of Lagrangian-based particle transport using the non-Boussinesq modeling of the buoyancy effects. An operating room including staffs and a patient with realistic human geometries and two surgery lights are included in simulations. The laminar airflow system is placed on the ceiling with a surrounding fixed-height partial wall and the air barrier supply grills. Effects of density change in mixed convection flow regime are included by the non-Boussinesq modeling of the exact air density variation. The predicted mean vote, the age of air, the colony-forming units per cubic meter, the average temperature, the average velocity, the relative humidity, the density distribution, and the positions of particles are calculated to assess the indoor air ventilation quality. A total of 27 simulation cases have been considered to determine the impact of three main design factors including the laminar airflow system area, the supply air, and the air barrier velocities on the performance of the system. It is concluded that for the curtain velocity of 2 m/s, the thermal comfort reduces with increasing the laminar airflow velocity, but for the third staff, the results show that for small laminar airflow areas, the speed of the inlet port should be reduced and for the larger sizes, the inverse of this trend is recommended. Moreover, for all cases the humidity varies within the range of 55%–56%, which agrees well with the suggested standard humidity range between 50% and 60%. It is concluded that the cases of the laminar airflow velocity equal to 0.3 and 0.5 at the curtain velocity of 1 m/s are generally more appropriate than other cases due to less accommodation of particles near the entire body of the patient.