Ram air fan outer housing

Abstract

A ram air fan outer housing for directing air from a ram air fan rotor and air from a ram air bypass into a ram air fan outlet. The outer housing includes an outer cylinder with a ram air fan rotor end and a ram air fan outlet end. The ram air fan rotor end and the ram air fan outlet end are at opposite ends of an axis of the outer cylinder. A plenum is joined at a joint region for directing air from the ram air bypass into the outer cylinder. The plenum includes two plenum ridges with one at each of two walls of the plenum. The two walls of the plenum are parallel to the axis of the outer cylinder. Each of the two plenum ridges includes a protruding section of the corresponding plenum wall.

1 . A ram air fan outer housing for directing air from a ram air fan rotor and air from a ram air bypass into a ram air fan outlet, the outer housing comprising:
 an outer cylinder having a ram air fan rotor end and a ram air fan outlet end, the ram air fan rotor end and the ram air fan outlet end at opposite ends of an axis of the outer cylinder; and   a plenum joined to the outer cylinder at a joint region for directing air from the ram air bypass into the outer cylinder, the plenum comprising:
 two plenum ridges, one at each of two walls of the plenum, the two walls of the plenum being parallel to the axis of the outer cylinder; wherein each of the two plenum ridges comprises a protruding section of the corresponding plenum wall. 
   
     
     
         2 . The outer housing of  claim 1 , wherein the plenum ridges protrude to planes parallel to each other, and between 12.450 inches and 12.470 inches (or between 316.230 mm and 316.738 mm) from a parallel plane containing the axis of the outer cylinder. 
     
     
         3 . The outer housing of  claim 2 , wherein the plenum ridges each form an inverted T shape. 
     
     
         4 . The outer housing of  claim 1 , wherein the outer cylinder further comprises:
 an outer cylinder support ridge extending along at least a portion of the outer cylinder in a plane perpendicular to the axis of the cylinder, and comprising a protruding section of the outer cylinder wall.   
     
     
         5 . The outer housing of  claim 4 , wherein the outer cylinder support ridge protrudes between 0.290 inches and 0.310 inches (or between 7.37 mm and 7.87 mm) radially outward from the outer cylinder wall. 
     
     
         6 . The outer housing of  claim 1 , wherein a ratio of an external length of the outer cylinder to an external diameter of the outer cylinder at the ram air fan outlet end is no greater than 1.5827, wherein the external length of the outer cylinder is a distance from the ram air fan rotor end to the ram air fan outlet end in a direction parallel to the axis of the outer cylinder. 
     
     
         7 . The outer housing of  claim 1 , wherein a ratio of an external length of the outer cylinder to an external diameter of the outer cylinder at the ram air fan outlet end is no greater than 1.5827 and no less than 1.5720, wherein the external length of the outer cylinder is a distance from the ram air fan rotor end to the ram air fan outlet end in a direction parallel to the axis of the outer cylinder. 
     
     
         8 . The outer housing of  claim 1 , wherein an external length of the outer cylinder is between 26.755 inches and 26.875 inches (or between 679.58 mm and 682.63 mm) and an external diameter of the outer cylinder at the ram air fan outlet is between 16.980 inches and 17.020 inches (or between 431.29 mm and 432.31 mm). 
     
     
         9 . The outer housing of  claim 1 , wherein the joint region extends into each of the outer cylinder and the plenum to at least 0.500 inches (or at least 12.7 mm) beyond any point where the outer cylinder or the plenum forms a tangent to a radius of curvature of the joint region. 
     
     
         10 . The outer housing of  claim 1 , wherein the joint region extends into each of the outer cylinder and the plenum to between 0.500 inches and 2.000 inches (or between 12.70 mm and 50.80 mm) beyond any point where the outer cylinder or the plenum forms a tangent to a radius of curvature of the joint region. 
     
     
         11 . The outer housing of  claim 1 , wherein
 the outer cylinder includes walls comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite;   the plenum includes walls comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite; and   the joint region is comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite, the joint region laminate stacking sequence formed by interleaving the plurality of adjacent outer cylinder layers in the joint region with the plurality of adjacent plenum layers in the joint region.   
     
     
         12 . The outer housing of  claim 11 , wherein
 the outer cylinder laminate stacking sequence comprises at least four adjacent layers of plain-weave fiber-reinforced polymer composite, each layer of the four adjacent outer cylinder layers having a weave orientation such that a first outer cylinder layer and a fourth outer cylinder layer are oriented forty-five degrees from each of a second outer cylinder layer and a third outer cylinder layer, the second outer cylinder layer and the third outer cylinder layer sandwiched between the first outer cylinder layer and the fourth outer cylinder layer;   the plenum laminate stacking sequence comprises at least four adjacent layers of plain-weave fiber-reinforced polymer composite, each layer of the four adjacent layers having a weave orientation such that a first plenum layer and a fourth plenum layer are oriented forty-five degrees from each of a second plenum layer and a third plenum layer, the second plenum layer and the third plenum layer sandwiched between the first plenum layer and the fourth plenum layer; and   the joint region laminate stacking sequence comprises at least eight adjacent layers of plain-weave fiber-reinforced polymer composite, the joint region laminate stacking sequence formed by interleaving the four adjacent outer cylinder layers in the joint region with the four adjacent plenum layers in the joint region.   
     
     
         13 . The outer housing of  claim 1 , wherein the outer housing is comprised by a ram air fan assembly, wherein the ram air fan assembly further comprises:
 a fan housing;   a fan motor attached to the fan housing;   a fan rotor;   a thrust shaft connecting the fan motor to the fan rotor;   an inlet housing connected to the fan housing;   a bearing housing attached to the fan housing; and   an inner housing attached to the bearing housing.   
     
     
         14 . The outer housing of  claim 13 , wherein the outer housing is connected to the fan housing and contains the bearing housing, the inner housing, and a portion of the fan housing. 
     
     
         15 . A ram air fan outer housing for directing air from a ram air fan rotor and air from a ram air bypass into a ram air fan outlet, the outer housing comprising:
 an outer cylinder having a ram air fan rotor end and a ram air fan outlet end, the ram air fan rotor end and the ram air fan outlet end at opposite ends of an axis of the outer cylinder, wherein the outer cylinder includes walls comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite, wherein the outer cylinder laminate stacking sequence comprises at least four adjacent layers of plain-weave fiber-reinforced polymer composite, each layer of the four adjacent outer cylinder layers having a weave orientation such that a first outer cylinder layer and a fourth outer cylinder layer are oriented forty-five degrees from each of a second outer cylinder layer and a third outer cylinder layer, the second outer cylinder layer and the third outer cylinder layer sandwiched between the first outer cylinder layer and the fourth outer cylinder layer; and   a plenum joined to the outer cylinder at a joint region for directing air from the ram air bypass into the outer cylinder, wherein the joint region is comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite, the joint region laminate stacking sequence formed by interleaving the plurality of adjacent outer cylinder layers in the joint region with the plurality of adjacent plenum layers in the joint region, wherein the joint region laminate stacking sequence comprises at least eight adjacent layers of plain-weave fiber-reinforced polymer composite, the joint region laminate stacking sequence formed by interleaving the four adjacent outer cylinder layers in the joint region with the four adjacent plenum layers in the joint region,   the plenum comprising:
 two plenum ridges, one at each of two walls of the plenum, the two walls of the plenum being parallel to the axis of the outer cylinder; wherein each of the two plenum ridges comprises a protruding section of the corresponding plenum wall, and 
 walls comprised of a laminate stacking sequence of a plurality of adjacent layers of plain-weave fiber-reinforced polymer composite, wherein the plenum laminate stacking sequence comprises at least four adjacent layers of plain-weave fiber-reinforced polymer composite, each layer of the four adjacent layers having a weave orientation such that a first plenum layer and a fourth plenum layer are oriented forty-five degrees from each of a second plenum layer and a third plenum layer, the second plenum layer and the third plenum layer sandwiched between the first plenum layer and the fourth plenum layer. 
   
     
     
         15 . The outer housing of  claim 1 , wherein the plenum ridges protrude to planes parallel to each other, and between 12.450 inches and 12.470 inches (or between 316.230 mm and 316.738 mm) from a parallel plane containing the axis of the outer cylinder. 
     
     
         17 . The outer housing of  claim 1 , wherein the outer cylinder further comprises:
 an outer cylinder support ridge extending along at least a portion of the outer cylinder in a plane perpendicular to the axis of the cylinder, and comprising a protruding section of the outer cylinder wall.   
     
     
         18 . The outer housing of  claim 1 , wherein a ratio of an external length of the outer cylinder to an external diameter of the outer cylinder at the ram air fan outlet end is no greater than 1.5827, wherein the external length of the outer cylinder is a distance from the ram air fan rotor end to the ram air fan outlet end in a direction parallel to the axis of the outer cylinder. 
     
     
         19 . The outer housing of  claim 1 , wherein the joint region extends into each of the outer cylinder and the plenum to at least 0.500 inches (or at least 12.7 mm) beyond any point where the outer cylinder or the plenum forms a tangent to a radius of curvature of the joint region. 
     
     
         20 . A method for installing a ram air fan outer housing comprising an outer cylinder and a plenum attached to the outer cylinder, the outer cylinder comprising a flanged surface perpendicular to an axis of the outer cylinder, the method comprising:
 inserting a ram air fan housing of a ram air fan assembly into the outer cylinder such that a bearing housing attached to the fan housing is contained within the outer housing;   positioning the inserted fan housing such that the flanged surface of the outer cylinder abuts a corresponding flanged surface of the fan housing;   bolting the positioned fan housing to the outer cylinder;   connecting electrical wires from the fan housing to a terminal box attached to the outer cylinder;   bolting a cooling air duct to a cooling air flange on the outer cylinder; and   installing the ram air fan assembly in an environmental control system.