A study on the effects of porosity on discharge coefficient in cross-ventilated buildings based on wind tunnels experiments

Takashi Kurabuchi, Yoshihiko Akamine, Masaaki Ohba, Tomoyuki Endo, Tomonobu Goto, Motoyasu Kamata

Research output: Contribution to journalArticlepeer-review

9 Citations (Scopus)

Abstract

A study was performed on the effects of porosity on discharge coefficient and airflow characteristics under the condition where uniform approaching flow directly faces to and enters the opening by using wind tunnel experiment and CFD analysis. The evaluation was performed on porosities in the range 0.4% - 64%. The results of wind tunnel experiments suggest that the discharge coefficient increases when the porosity is higher. The results of CFD analysis reveal that the contraction of airflow when it passes through the opening is correlated with discharge coefficient, and that the discharge coefficient increases when flow contraction does not occur. When porosity increases, the retardment of the streamtube ceases to occur in the region upstream of the opening, and this leads to the elimination of flow contraction, hence the increase of discharge coefficient. When we evaluated the limitation of application of the local dynamic similarity model on porosity, the effectiveness of the model was confirmed well when the porosity was 16% or lower regardless of wind direction. The validity of the model was also confirmed under the condition where airflow goes along the wall surface before reaching the opening even when the porosity was 36% or more.

Original languageEnglish
Pages (from-to)67-78
Number of pages12
JournalInternational Journal of Ventilation
Volume5
Issue number1
DOIs
Publication statusPublished - 2006 Jun
Externally publishedYes

Keywords

  • CFD analysis
  • Discharge coefficient
  • Flow contraction
  • Local dynamic similarity model
  • Porosity
  • Wind tunnel experiment

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Civil and Structural Engineering
  • Building and Construction
  • Electrical and Electronic Engineering

Fingerprint Dive into the research topics of 'A study on the effects of porosity on discharge coefficient in cross-ventilated buildings based on wind tunnels experiments'. Together they form a unique fingerprint.

Cite this