influence of a vent hood at the exit of exhaust flue gas and flue baffles in the firetube on the temperature and flow fields of a gas tank water heater, as well as thestructure and amount of heat transferred to the water tank has been studiednumerically using two-dimensional steady state finite element simulation.observations show that without a vent hood, there is a downward gas flow in theflu...

A wake-controlled exterior hood was developed to overcome the negative influence of cross draft on an exterior hood and avoid the operation inconvenience caused by the enclosure of an airflow capture booth. This new type of local exterior hood used the hood suction flow to stabilize the dynamic vortex shedding that was induced when a crossflow passed over a blockage plate, and therefore formed ...

Health care workers (HCW) are exposed to ribavirin aerosol during therapy of infants with respiratory syncytial virus infections. To assess the degree of HCW exposure, we analyzed air samples from patient rooms and HCW personal breathing zones during ribavirin aerosol delivery by ventilator (two samples), oxygen hood (two samples), and a new vacuum exhaust hood (four samples). HCW exposure to r...

A novel range hood (NRH) consisting of a high-efficiency particulate air (HEPA) filter circulation component and exhaust was designed to improve indoor quality. The HEPA with an airflow rate 72 l/s used remove the matter generated by cooking activities return filtered clean room. reject both other pollutants outdoors. Field measurements were carried out in open kitchen two-floor residential hou...

The microbiological control efficiency of two class 100 laminar down-flow hoods was determined by using aerosols of Bacillus subtilis var. niger spores. The first unit challenged utilized a slanted eyelid to partially enclose the front work opening. This hood showed nearly perfect control of ambient organisms in the work area. It also gave a 10(6) or greater drop in the number of organisms pass...