Impact of plenum on air distribution and thermal stratification in underfloor air distribution system

Jianlei Niu, Chong Shen, Naiping Gao, Kun Dong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

2 Citations (Scopus)


The real performance of under-floor air distribution (UFAD) system in the office was studied by focusing on the impact of plenum on the indoor air motion and thermal stratification. The practical thermal stratification in an office with under-floor plenum was tested first. Numerical simulation was adopted to quantificationally analyze the impact of heat gains in the plenum on the indoor thermal environment. The results show that the air in the plenum undertakes approximately 40% of indoor cooling load. The supply air temperature from air diffusers increases, leading to the decay of thermal stratification. The increase of flow rate will decrease the vertical temperature gradient as well. More attention should be paid to the influence of plenum on indoor thermal balance and flow field. The advantage of UFAD system depends on the good sealing and thermal insulation measure at the raised floor.
Original languageEnglish
Pages (from-to)454-459
Number of pages6
JournalTongji Daxue Xuebao/Journal of Tongji University
Issue number3
Publication statusPublished - 1 Jan 2014


  • Air motion
  • Plenum
  • Thermal stratification
  • Under-floor air distribution

ASJC Scopus subject areas

  • General

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