Assessment of virtual thermal manikins for thermal comfort numerical studies. Verification and validation

This study is a part of a larger experimental and numerical campaign intended to evaluate the influence of the turbulence intensity at the inlet of the terminal air distribution systems on the local draft sensation and thermal discomfort of ventilation users. In this paper we present preliminary results of CFD simulations using a realistic model of human body along with an experimental validation. The model is further used in a piston distribution scheme to evaluate the influence of turbulence intensity on the comfort indicators. The recorded velocity, turbulence and temperature fields allowed us to estimate the distributions of DR, PPD and PMV indexes. For the investigated case, the results indicated a direct correlation.

Download Full-text

Experimental Investigation of the Ventilation Performance of Different Air Distribution Systems in an Office Environment—Cooling Mode

Energies ◽

10.3390/en12071354 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1354 ◽

Cited By ~ 2

Author(s):

Arman Ameen ◽

Mathias Cehlin ◽

Ulf Larsson ◽

Taghi Karimipanah

Keyword(s):

Distribution System ◽

Distribution Systems ◽

Ventilation System ◽

Impinging Jet ◽

Air Distribution ◽

Displacement Ventilation ◽

Cooling Mode ◽

Distribution Method ◽

Ventilation Performance ◽

Velocity Turbulence

The performance of a newly designed corner impinging jet air distribution method with an equilateral triangle cross section was evaluated experimentally and compared to that of two more traditional methods (mixing and displacement ventilation). At nine evenly chosen positions with four standard vertical points, air velocity, turbulence intensity, temperature, and tracer gas decay measurements were conducted for all systems. The results show that the new method behaves as a displacement ventilation system, with high air change effectiveness and stratified flow pattern and temperature field. Both local air change effectiveness and air exchange effectiveness of the corner impinging jet showed high quality and promising results, which is a good indicator of ventilation effectiveness. The results also indicate that there is a possibility to slightly lower the airflow rates for the new air distribution system, while still meeting the requirements for thermal comfort and indoor air quality, thereby reducing fan energy usage. The draught rate was also lower for corner impinging jet compared to the other tested air distribution methods. The findings of this research show that the corner impinging jet method can be used for office ventilation.

Download Full-text