Abstract
The fan heater used for industry and residence has become smaller, lighter, and more silent as the result of improvement.
However there are problems that the fan heater size is large, and the noise is high due to air pressure loss of heat exchangers.
Therefore we have been developing the centrifugal type fan with the function of heat exchanger. The features of this
new type fan heater are that the fan heater size is very small and silent because the fan and the heat exchanger are in one
body. This paper described the effects of the flow between fan blades on the distribution of Nusselt number on the blade
surface of fans with different diameter. The heat transfer characteristics and the flow patterns in the fans with different
diameter were clarified by calculating the flow in the fan, and measuring the local heat transfer coefficient on the blade surface.
