Simulation of Ventilation Systems in a Protected Environment Using Computational Fluid Dynamics

Abstract

Computational simulations of mass and energy flow help in implementing alternative cooling systems in protected environments. The aim of this study was to model and simulate the interaction between external and internal environments of a protected environment by means of computational fluid dynamics (CFD) techniques and validate micrometeorological variables for subsequent comparison between natural and indirect ventilation by ground heat exchangers. At the first phase, the micrometeorological variables global solar radiation (Qg), air temperature (Tair), and air relative humidity (RH) were monitored. The second phase consisted of the numerical modeling of finite volumes, with validation through recorded data, as well as simulation and comparison of two ventilation systems. The functional relationship between simulated and recorded meteorological elements presented a good linear association, with coefficients of determination of 0.97, 0.93, and 0.94 for Qg, Tair, and RH, respectively. Simulation of indirect ventilation system by ground heat exchangers presented a reduction of 4 °C in Tair and 15% in RH compared to that recorded inside the environment. The natural ventilation system allowed a reduction of 1 °C in Tair when compared to the protected environment.

Numerical simulation of a mixed vertical ventilation system

“…For all mentioned cases, a qualitative agreement was found between the stream lines, velocities and temperatures current results and the mentioned literature [8,13,17,20].…”

“…Finally, qualitative observation on the studies performed by [8,17] and [20] might lead to conclusion that the physical nature of current results sounds correct, especially with [13] and [17]. In the study done by [8] there are two vertical inlets with vertical velocities while here they are opposite.…”

“…In the study done by [8] there are two vertical inlets with vertical velocities while here they are opposite. Finally, the mixed flow appearing in [20] comes out from the same point while here we have two distinct inlet and outlet that placed on one plane in two different locations.…”

“…Finally, the thermal field will be calculated and discussed. Qualitative comparison will be made with [8,17] and [20].…”

Representativeness of the field of rural buildings and ambience in Brazilian journals / Representatividade do campo dos edifícios rurais e do ambiente nas revistas brasileiras

“…The impact that a rural production building can cause on the production process itself, on the product and the workers, is very expressive. Especially in animal production, the quality of the physical environment 2,3,11,12,[21][22][23][24][25][26][27][28][29][30] (rooms, population density, construction materials, the ease of nutritional and sanitary management) and the quality of the indoor environment (pollutant gases, particulate materials, microorganisms, temperature and relative humidity, ventilation 11,[31][32][33] ) are distinctive factors in the quality of the process and product.…”