Fluid mixing structure

Abstract

A respiratory therapy system can have a flow generator adapted to provide gases to a patient. A gas passageway can be located in-line with the flow generator. The gas passageway can have a first portion adapted to receive a first gas and a second portion adapted to receive a second gas. The gas passageway can have a static mixer downstream of the first and second portions.

1 - 153 . (canceled) 
     
     
         154 . A static flow mixer configured to mix multiple gases comprising: 
 an inlet configured to receive at least two gases;   an outlet;   a first baffle positioned between the inlet and the outlet; and   a pinch defined between a downstream edge of the first baffle and a nearest downstream surface, wherein a length of the pinch is less than a height of the first baffle,   wherein, in use, gases exiting the static mixer are substantially uniformly mixed.   
     
     
         155 . The static flow mixer of  claim 154 , wherein the first baffle extends at a first angle relative to horizontal, the first baffle extending downstream relative to a gases flow entering the inlet in use. 
     
     
         156 . The static flow mixer of  claim 155 , wherein the first angle is in the range of 30 degrees to 70 degrees. 
     
     
         157 . The static flow mixer of  claim 154 , wherein in use, the first baffle causes a gases flow through the static flow mixer to move upwards and then sharply turn at the downstream edge of the first baffle. 
     
     
         158 . The static flow mixer of  claim 154 , further comprising a second baffle positioned between the first baffle and the outlet, wherein an upstream face of the second baffle comprises the nearest downstream surface. 
     
     
         159 . The static flow mixer of  claim 158 , wherein in use, the first baffle directs a gases flow through the static flow mixer toward the second baffle. 
     
     
         160 . The static flow mixer of  claim 158 , wherein at least one of the first and second baffles extends at an angle downstream relative to horizontal. 
     
     
         161 . The static flow mixer of  claim 158 , wherein the second baffle extends downward at a second angle relative to horizontal, the second baffle extending downstream relative to a gases flow entering the inlet in use. 
     
     
         162 . The static flow mixer of  claim 161 , wherein the second angle is in the range of 30 degrees to 70 degrees. 
     
     
         163 . The static flow mixer of  claim 158 , wherein in use, the second baffle directs a gases flow through the static flow mixer to move downwards and then sharply turn at a downstream edge of the second baffle. 
     
     
         164 . The static flow mixer of  claim 154 , wherein the length of the pinch is less than half of the height of the first baffle. 
     
     
         165 . The static flow mixer of  claim 154 , wherein the length of the pinch is in the range of one-third to one-fourth of the height of the first baffle. 
     
     
         166 . The static flow mixer of  claim 154 , wherein in use, the pinch is configured to accelerate a gases flow passing through the static flow mixer. 
     
     
         167 . The static flow mixer of  claim 154 , wherein the length of the pinch is uniform across a width of the static flow mixer. 
     
     
         168 . The static flow mixer of  claim 154 , wherein in use, a gases flow passing through the static flow mixer swirls and expands after passing the first baffle and passing through the pinch. 
     
     
         169 . The static flow mixer of  claim 158 , wherein a second pinch is defined between a downstream edge of the second baffle and a bottom wall of the static flow mixer. 
     
     
         170 . The static flow mixer of  claim 169 , wherein in use, a gases flow passing through the static flow mixer swirls and expands after passing the second baffle and passing through the second pinch. 
     
     
         171 . The static flow mixer of  claim 158 , further comprising a bridge extending between and connecting the first baffle and the second baffle, wherein the bridge splits a gases flow. 
     
     
         172 . The static flow mixer of  claim 158 , wherein at least a portion of at least one surface of at least one of the first and second baffles is roughened. 
     
     
         173 . The static flow mixer of  claim 154 , wherein in use, the at least two gases enter the inlet along different axes. 
     
     
         174 . The static flow mixer of  claim 154 , wherein in use, a flow of one of the at least two gases is separated from a flow of another of the at least two gases as the at least two gases enter the inlet. 
     
     
         175 . The static flow mixer of  claim 154 , wherein in use, the at least two gases enter the inlet at opposite sides of the inlet. 
     
     
         176 . The static flow mixer of  claim 154 , wherein a gases flow exiting the static flow mixer through the outlet is laminar.