Cooling system having anti-recirculation feature

Abstract

A cooling system is disclosed for use with an engine. The cooling system may have a heat exchanger fluidly connectable to the engine, and a fan situated adjacent the heat exchanger and configured to generate a flow of air through the heat exchanger. The cooling system may also include an anti-recirculation feature located adjacent the fan and configured to block the flow of air at a center of the fan and allow air to flow at a periphery of the fan.

What is claimed is: 
     
         1 . A cooling system for an engine, comprising:
 a heat exchanger fluidly connectable to the engine;   a fan situated adjacent the heat exchanger and configured to generate a flow of air through the heat exchanger; and   an anti-recirculation feature located adjacent the fan and configured to block the flow of air at a center of the fan and allow air to flow at a periphery of the fan.   
     
     
         2 . The cooling system of  claim 1 , wherein the anti-recirculation feature includes a generally disc-shaped solid member. 
     
     
         3 . The cooling system of  claim 2 , wherein:
 the fan includes:
 a hub; and 
 a plurality of fan blades extending radially outward from the hub; and 
   the anti-recirculation feature has an outer diameter greater than an outer diameter of the hub and smaller than an outer diameter of the plurality of fan blades.   
     
     
         4 . The cooling system of  claim 3 , wherein the outer diameter of the anti-recirculation feature is about 60-80% of the outer diameter of the plurality of fan blades. 
     
     
         5 . The cooling system of  claim 3 , wherein the outer diameter of the anti-recirculation feature is about 550-600 mm. 
     
     
         6 . The cooling system of  claim 2 , wherein the anti-recirculation feature is an integral portion of an engine grill and disposed opposite the heat exchanger relative to the fan. 
     
     
         7 . The cooling system of  claim 6 , wherein the engine grill includes a plurality of perforations formed in a pattern around the anti-recirculation feature. 
     
     
         8 . The cooling system of  claim 7 , wherein the plurality of perforations extend from an outer diameter of the anti-recirculation feature past an outer diameter of blades of the fan. 
     
     
         9 . The cooling system of  claim 6 , wherein:
 the engine grill includes:
 a generally planar first portion; and 
 a generally planar second portion tilted inward from the first portion toward the fan; and 
   the anti-recirculation feature extends at least partway across the first and second portions.   
     
     
         10 . The cooling system of  claim 9 , wherein the engine grill includes a plurality of transverse corrugations that extend across the anti-recirculation feature. 
     
     
         11 . The cooling system of  claim 6 , further including a cowling configured to connect the engine grill to the fan. 
     
     
         12 . An engine grill, comprising:
 an end portion;   a plurality of perforations formed within the end portion in a pattern around a middle of the end portion; and   an anti-recirculation feature situated at a middle of the end portion within the pattern of the plurality of perforations.   
     
     
         13 . The engine grill of  claim 12 , wherein the anti-recirculation feature is a generally disc-shaped solid member. 
     
     
         14 . The engine grill of  claim 13 , wherein an outer diameter of the anti-recirculation feature is about 550-600 mm. 
     
     
         15 . The engine grill of  claim 13 , wherein:
 the end portion includes:
 a generally planar first portion; and 
 a generally planar second portion tilted away from the first portion; and 
   the disc-shaped solid member extends at least partway across the first and second portions.   
     
     
         16 . The engine grill of  claim 15 , wherein the engine grill includes a plurality of transverse corrugations that extend across the anti-recirculation feature. 
     
     
         17 . A power unit, comprising:
 an engine disposed within an engine housing;   a heat exchanger fluidly connected to the engine and disposed within the engine housing at one end of the engine;   a fan disposed within the engine housing adjacent the heat exchanger and configured to generate a flow of air through the heat exchanger;   an engine grill disposed adjacent the fan and having:
 an end portion; 
 a plurality of perforations formed within the end portion in a pattern around a middle of the end portion and configured to allow passage of the flow of air generated by the fan; and 
 disc-shaped solid member situated at the middle of the end portion within the pattern of the plurality of perforations and configured to block the flow of air at a center of the fan and allow air to flow at a periphery of the fan; and 
   an engine cowling configured to at least partially close off the engine housing and connect the engine grill to the fan.   
     
     
         18 . The power unit of  claim 17 , wherein the engine housing includes a plurality of air inlets configured to direct air to the fan. 
     
     
         19 . The power unit of  claim 18 , wherein the fan is configured to draw air from the plurality of air inlets through the heat exchanger and push the air around the disc-shaped solid member and out of the engine housing through the plurality of perforations. 
     
     
         20 . The power unit of  claim 19 , wherein an outer diameter of the disc-shaped solid member is about 60-80% of an outer diameter of the fan.