Experimental investigation of a ventilation system based on wall confluent jets
2014 (English)In: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 80, 18-31 p.Article in journal (Refereed) Published
The flow behavior of isothermal and non-isothermal wall confluent jets (WCJ) ventilation system was investigated experimentally in a mock-up office environment. Two flow regions were identified: first, a primary region is developed below the supply device, with axis along the inlet wall, and a secondary wall-jet forms along the floor. The velocity and temperature fields were recorded by traversing a hot wire and thermistor anemometers for both primary and secondary regions. The results show self-similarity characteristic of the velocity and temperature profiles for both isothermal and non-isothermal WCJ. Maximum velocity decay and its spreading rate are linear and independent of the inlet airflow rate. Minimum temperature difference and its spread also show linear decay. The spreading rates for maximum velocity are similar in both the primary and secondary regions normal to the inlet wall and floor, respectively, which is consistent with previous studies on wall jets. The variation of draught rating is evaluated via mean velocity, turbulence intensity and temperature. Although the WCJ has slow velocity decay, which enables it to cover almost the entire floor of the test room, the draught is acceptable in the occupied zone according to ISO 7730. PMV (predicted mean vote) and PPD (predicted percentage dissatisfied) are presented for the occupied zone of the room.
Place, publisher, year, edition, pages
2014. Vol. 80, 18-31 p.
Draught rate, Measurement, Supply device, Thermal comfort indices, Ventilation system, Wall confluent jets, Floors, Inlet flow, Isotherms, Measurements, Thermal comfort, Velocity, Ventilation, Experimental investigations, Minimum temperature differences, Temperature profiles, Thermal comfort index, Turbulence intensity, Velocity and temperature fields, Ventilation systems, Air, airflow, experimental study, jet flow, measurement method, temperature profile, turbulence, velocity profile
IdentifiersURN: urn:nbn:se:hig:diva-18465DOI: 10.1016/j.buildenv.2014.05.011ISI: 000340323300003ScopusID: 2-s2.0-84902119008OAI: oai:DiVA.org:hig-18465DiVA: diva2:770209