| 摘要 |
<p>A waterlift silencer and method for reducing the acoustic energy of a fluid mixture of engine exhaust gas and a liquid coolant and limiting back pressure exerted by the silencer on an engine, particularly as applied to engines located below the waterline of a marine vessel. The silencer has two or more mixture-expelling conduits through which the fluid mixture is dynamically lifted above the silencer to a point above the waterline. The mixture-expelling conduits are sequentially operated in order to maintain exhaust gas volume flow rates high enough to partially atomize the liquid and thus allow it to be expelled upward, while maintaining a minimal back pressure on the engine throughout the full range of normal engine operating speeds. Two mixture-expelling tubes may be used. The first tube typically has a diameter that is equal to or smaller than the diameter of the second tube, and has an opening in its bottom portion that is further from the bottom of the holding chamber than is an opening in the bottom portion of the second tube. When the engine is started, the pressure in the holding chamber pushes the free water level of the fluid mixture down to the opening in the first tube, which may thus dynamically lift the fluid mixture out of the chamber. As the engine speed increases, the free water level reaches the opening in the second tube, so that the fluid mixture is carried out through both tubes. The first tube may be located within the second tube.</p> |
