Combustion system for an internal combustion engine

Abstract

A combustion system for an internal combustion engine includes combustion chamber that is defined between a cylinder head and a top surface of a piston. The combustion system also includes a fuel injector having an injector tip. The injector tip defines a nozzle disposed in fluid communication with the combustion chamber for dispensing a fuel jet into the combustion chamber. A bluff body is positioned within the combustion chamber such that an axis of the dispensed fuel jet is incident on an anterior portion of the bluff body proximal to the injector tip. The anterior portion has a contour that is adapted to split the dispensed fuel jet into at least two turbulent fuel streams and facilitate mixing of each fuel stream with an oxidant present in the combustion chamber.

What is claimed is: 
     
         1 . A combustion system for an internal combustion engine, the combustion system comprising:
 a combustion chamber defined between a cylinder head and a top surface of a piston;   a fuel injector having an injector tip defining a nozzle, the nozzle disposed in fluid communication with the combustion chamber to dispense a fuel jet into the combustion chamber; and   a bluff body positioned within the combustion chamber such that an axis of the dispensed fuel jet is incident on an anterior portion of the bluff body proximal to the injector tip, the anterior portion having a contour adapted to split at least a portion of the dispensed fuel jet into at least two turbulent fuel streams and facilitate mixing of each fuel stream with an oxidant present in the combustion chamber.   
     
     
         2 . The combustion system of  claim 1 , wherein the bluff body has a posterior portion defining a first orifice transverse to the axis of the dispensed fuel jet and a second orifice distal from the injector tip and parallel to the axis of the dispensed fuel jet. 
     
     
         3 . The combustion system of  claim 2 , wherein the first orifice is in fluid communication with the second orifice via a passageway such that the first orifice is configured to entrain an oxidant from a portion of the combustion chamber adjacent the first orifice and communicate the entrained oxidant to a portion of the combustion chamber adjacent the second orifice via the passageway. 
     
     
         4 . The combustion system of  claim 3 , wherein a contour of the posterior portion is at least one of: convergent and divergent from the axis of the dispensed fuel jet. 
     
     
         5 . The combustion system of  claim 1 , wherein the contour of the anterior portion is convex opposing a flow direction of the fuel jet. 
     
     
         6 . The combustion system of  claim 5 , wherein a maximum perimeter of the anterior portion is one of: at least equal to and smaller than a perimeter associated with a spray pattern of the dispensed fuel jet that is incident on the anterior portion. 
     
     
         7 . The combustion system of  claim 1 , wherein the contour of the anterior portion includes an apex opposing a flow direction of the fuel jet. 
     
     
         8 . The combustion system of  claim 1 , wherein the bluff body is at least one of: oblong, spherical, and polyhedral in shape. 
     
     
         9 . The combustion system of  claim 8 , wherein the polyhedral shape of the bluff body defines a plurality of concave and convex portions in an alternating arrangement about the axis of the dispensed fuel jet. 
     
     
         10 . The combustion system of  claim 9 , wherein the first orifice is located on at least one of: the concave and convex portions of the bluff body. 
     
     
         11 . The combustion system of  claim 1 , wherein the bluff body is positioned at a pre-determined distance from the nozzle of the injector tip to impart turbulence by generating a wake in the incident fuel jet. 
     
     
         12 . The combustion system of  claim 1 , wherein the bluff body is a screen mesh having a plane angularly disposed to the axis of the fuel jet. 
     
     
         13 . The combustion system of  claim 12 , wherein the screen mesh comprises a plurality of wires, each wire from the plurality of wires being disposed at a pre-specified distance from an adjacent one of the wires to render the screen mesh with a pre-determined porosity. 
     
     
         14 . The combustion system of  claim 13 , wherein each wire has at least one of an oblong, circular, and polygonal cross-section. 
     
     
         15 . The combustion system of  claim 13 , wherein the screen mesh is positioned at a pre-determined distance from the injector tip to facilitate at least one wire from the plurality of wires in imparting turbulence by generating a wake in the incident fuel jet. 
     
     
         16 . The combustion system of  claim 12 , wherein the screen mesh is positioned adjacent to the nozzle on the injector tip of the fuel injector. 
     
     
         17 . The combustion system of  claim 12 , wherein a contour of the screen mesh is adapted to correspond with a contour of the injector tip. 
     
     
         18 . The combustion system of  claim 12 , further comprising a duct disposed within the combustion chamber, wherein the screen mesh is attached to an end of the duet distal from the nozzle. 
     
     
         19 . An internal combustion engine comprising:
 a piston slidably disposed within a cylinder such that a top surface of the piston and a cylinder head adjoining the cylinder are in reciprocally opposing relation to one another for defining the combustion chamber therebetween; and   a combustion system associated with the combustion chamber, the combustion system comprising:
 a fuel injector having an injector tip defining a nozzle, the nozzle disposed in fluid communication with the combustion chamber to dispense a fuel jet into the combustion chamber; and 
 a bluff body positioned within the combustion chamber such that an axis of the dispensed fuel jet is incident on an anterior portion of the bluff body proximal to the injector tip, the anterior portion having a contour adapted to split at least a portion of the dispensed fuel jet into at least two turbulent fuel streams and facilitate mixing of each fuel stream with an oxidant present in the combustion chamber.