| 摘要 |
PURPOSE: To obtain a muffler for use with an underwater vehicle which produces a low noise and does not decrease the propelling efficiency, and an underwater vehicle provided with the muffler. CONSTITUTION: A muffler 31 is mechanically attached to an exhaust tube or aft end of an underwater vehicle 11 and has a hydrodynamic shape and perforated exterior that results in the production of less noise by the vehicle 11. Large bubbles have been determined to be offensive due to lower frequency collapsing noise which produces a louder vehicle exhaust. The muffler is perforated with holes 33 to break up the flow 13 of exhaust gas from the vehicle into small diameter bubbles that are emitted into the water. The muffler has a contoured outer wall 34 that matches the contour of the underwater vehicle 11 to provide for the hydrodynamic flow of water around the vehicle 11 as it is propelled through the water. The muffler eliminates hydrodynamic voids at the aft end of the vehicle 11 that would normally allow smaller bubbles to coalesce into large bubbles. |
