Patent ID: 9115667
Filing Date: 2015-08-25
Classification: F01N,F02K

Abstract:
1. A noise suppressor for gas jets comprising in cooperating arrangement: i) a lower vent stack having installed at its upper end a flow controlling means having a total open cross sectional area less than the cross sectional area of said lower vent stack; ii) above and co-operating with said lower vent stack an upper vent stack having a cross section area larger, relative to the open cross sectional area of said flow controlling means and sufficient to cause supersonic flow at the upper stack exit absent component iii) below, and a ratio of length to diameter of at least about 5:1; iii) within the upper vent stack, a bed of inert, rigid (solid or hollow) tightly packed granulae, said bed having the height at least equivalent to one diameter of said upper stack, and having a total cross sectional area of interstitial voids among the granulae not less than about 2.25 times the cross sectional area of the total open area of said flow controlling means.