| 摘要 |
<p>A forced draft burner unit comprises: a flame chamber, a conduit for conducting fuel to the flame chamber, a blast tube for conducting air from an air opening on a side of the blast tube adjacent first end of the blast tube to a second end of the blast tube adjacent the flame chamber. An impeller-type fan supplies pressurized air to the air opening. The fan has an axis of rotation parallel to the longitudinal axis of the blast tube and has impeller blades passing within the blast tube as the fan rotates, so the pressurized air enters the air opening generally tangential to the blast tube and passes along the blast tube to the second end in vortical flow. There are vanes for mixing the fuel and air in the flame chamber.</p> |
