BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//CERN//INDICO//EN
BEGIN:VEVENT
SUMMARY:The effect of ventilation on the thermal performance of an energy 
 efficient house
DTSTART;VALUE=DATE-TIME:20110714T150000Z
DTEND;VALUE=DATE-TIME:20110714T170000Z
DTSTAMP;VALUE=DATE-TIME:20260715T050237Z
UID:indico-contribution-4862@events.saip.org.za
DESCRIPTION:Speakers: Thabiso Vincent Mthimunye (ufh)\nAn energy efficient
  passive solar house was designed\, constructed and its natural ventilatio
 n efficiency monitored.  Carbon tracer test was used to measure the ventil
 ation efficiency of each ventilation component. Windows were found to have
  higher impact on the ventilation rate than doors. The correct operation o
 f the ventilation components was found to be the main contribution factor 
 in natural ventilation.Tracer gas tests were conducted over a period of ti
 me to measure actual air change rates. Carbon dioxide was injected into th
 e house and its concentration monitored over time to determine how quickly
  the gas dissipates through the house’s envelope. The west side ventilat
 ion components were used to control the indoor environment by regulating t
 he amount of air flowing into the house. A carbon dioxide sensor was place
 d in the centre of the house at a height of about 0.45 m above the floor. 
 A fan was used to pump the indoor air into the sensor at a rate of about 3
 00 ml/min. To investigate the effects of each of the ventilation component
  configurations\, the ventilation rate tests were done in four configurati
 ons. A carbon dioxide sensor connected to a CR1000 data logger and a compu
 ter was used to monitor carbon dioxide concentration in the house. \nresul
 ts:The tracer gas technique was used to measure the air exchange rate. The
  average indoor and outdoor temperatures during these tests were\, Tin = 2
 0 °C and Tout =17 °C\, and an average wind speed of 0.5 m/s blowing from
  W(600 150)N.when both windows and doors were opens. Results indicate that
  the concentration decays exponentially to the background concentration wi
 thin a period of 16 minutes. Assuming that the west window and door are th
 e only paths through which the westerly winds enter the house\, then the m
 ass air flow rate through the door and window is approximated.Take the ave
 rage air density to be 1.2 kg/m3\, an average indoor and outdoor pressure 
 difference to be 4 Pa. For wide-open windows and doors\, the opening area 
 is the sum of the windows and doors areas\, which gives 2.06 m2 and taking
  the discharge coefficient Cd=0.6  the average mass airflow was found to b
 e approximately 3.83 kg/s.Natural ventilation varies greatly on local fact
 ors such as wind speed and temperature which also influence at which occup
 ants open ventilation components.\n\nhttps://events.saip.org.za/event/7/co
 ntributions/4862/
LOCATION: Asteria
URL:https://events.saip.org.za/event/7/contributions/4862/
END:VEVENT
END:VCALENDAR