| 摘要 |
<p>An apparatus (10, 212) for mixing a gas and a liquid is disclosed. The apparatus is comprised of a hollow outer housing (22) and a hollow inner tube (24) received for rotary motion within the outer housing (22). A motor (61) is attached to the outer housing (22) adjacent a first end thereof and is drivingly coupled to a first end of the inner tube (24). The inner tube (24) has a support tube (214) which extends beyond the second end of the outer housing (22). Propeller blades (216) are attached to the support tube (214) for rotation therewith. An inlet (82) is formed in the inner tube (24) for admitting a gas to the hollow interior of the inner tube (24). The support tube (214) has a diffusion section (222) that extends below the propeller blades (216). The propeller mechanism (210), which includes the support tube (214) and the blades (216), is designed to increase the oxygen transfer efficiency of the apparatus (10, 212) over that provided by a standard marine propeller (48). Each propeller blade (216) has an impelling surface (232) with a varying rake which changes to a more positive rake from a leading end (226) to a tail end (228) of each propeller blade (216). Plates (238, 240, 242) are attached to the air outlet end (224) of the support tube (214). Lower portions (250) of the plates (240, 242) are bent backward in the direction in which the propeller mechanism (210) is to be rotated.</p> |
