High flow pressure relief valve

A gas pressure relief valve for automatic venting of a high pressure source to an area of lower pressure with high volumetric flow in response to pressure build-up of said source, said valve comprising a valve body, an elongated recess in said body, a passage connecting one end of said recess with said source for receiving fluid flow therefrom through said recess toward the opposite end thereof, a poppet element fitted in said recess other end and adapted for normally closing said other end, said poppet element including a tubular sleeve fitted axially and slidably within said recess, said sleeve opening at one end into said passage, a closure extending across the other end of said sleeve and configured for providing a gas-tight sealing engagement with said valve body at said opposite end of said recess, said sleeve defining a second passage having a transverse cross-sectional area at least as great as that of the first said passage, said second passage being of substantially constant diameter and forming with said first passage a flow path through said valve substantially devoid of any constriction productive of a vena contracta within said flow path, said sleeve having at least one gas release port providing a cross-sectional area at least as great as the transverse cross-sectional area of said second passage, said port being proximate said closure, means for resiliently urging said poppet element toward said one end of said recess defining a valve seat for maintaining said gas-tight sealing engagement, said valve body terminating substantially commensurate with said valve seat, thereby to avoid extending beyond said poppet any fluid flow restrictive structure, said poppet element being axially movable away from said valve seat of said recess in response to a predetermined value of gas pressure differential between said source and area of lower pressure for opening said port to said area of lower pressure, said sleeve effectively defining a nozzle for maintaining a constant dynamic pressure upon said closure upon movement of said poppet element away from said valve seat, said poppet element upon said movement introducing into said flow path no constriction productive of a vena contracta within said flow path, the extent of opening of said port being dependent upon the differential in gas pressure between said source and lower pressure area, said poppet being maintained in a position opening of said port by the dynamic impact of a gaseous stream flowing through said second pressure against said closure, and whereby said gaseous stream during flow along said flow path exhibits substantially no divergence within said valve, said closure being flanged, said closure including an area of sealing engagement with said valve body having a sealed diameter which is less than the effective diameter of said flanged closure, said flanged closure extending across said gaseous stream during said flow, said impact of said gaseous stream upon said flanged closure thereby preventing said closing engagement with said valve body until said gas pressure differential is less than said predetermined valve.