Cooling Jacket with Porous Matrix

Abstract

The fluids and heat transfer theory for regenerative cooling of a rocket combustion chamber with a porous media coolant jacket is presented. This model is useful for calculating temperature distributions in a coolant fluid and combustion chamber or heat source as well as the associated fluid pressure drop through the coolant jacket. This model for fluids and heat transfer theory can be used to design a regeneratively cooled rocket engine.

1 . A cooling jacket comprising:
 a fluid-impermeable inner wall defining a combustion chamber bounded by the cooling jacket;   a fluid-impermeable outer shell forming a channel between the inner wall and the outer shell; and   a thermally conductive porous matrix occupying the channel, wherein the cooling jacket includes an inlet configured to receive a coolant fluid into the porous matrix at one end of the cooling jacket and an outlet configured to expel the coolant fluid from the porous matrix at an opposite end of the cooling jacket into the combustion chamber.   
     
     
         2 . The cooling jacket of  claim 1 , wherein the porous matrix includes structures providing multiple direct thermal connections between the inner wall and the outer shell. 
     
     
         3 . The cooling jacket of  claim 1 , wherein the porous matrix includes structures directing mixing of the coolant fluid within the channel. 
     
     
         4 . The cooling jacket of  claim 3 , wherein the porous matrix structures directing mixing of the coolant fluid include microtubes. 
     
     
         5 . The cooling jacket of  claim 3 , wherein the porous matrix structures directing mixing of the coolant fluid include ribbon structures. 
     
     
         6 . The cooling jacket of  claim 1 , wherein the channel is a contoured cooling chamber. 
     
     
         7 . The cooling jacket of  claim 1 , wherein the porous matrix follows a contour of the channel. 
     
     
         8 . The cooling jacket of  claim 1 , wherein the inner wall, the porous matrix, and the outer shell are formed from stacked and aligned metal layers of the cooling jacket. 
     
     
         9 . The cooling jacket of  claim 1 , wherein the porous matrix includes one or more of a microfluidic porous lithographic structure, a microfluidic porous metal foam, and an open cell metal foam. 
     
     
         10 . The cooling jacket of  claim 1 , wherein the porous matrix is non-catalytic with the coolant fluid. 
     
     
         11 . The cooling jacket of  claim 1 , wherein the porous matrix includes one or more of aluminum, nickel, and stainless steel. 
     
     
         12 . The cooling jacket of  claim 1 , wherein the porous matrix has a porosity of less than 80%. 
     
     
         13 . The cooling jacket of  claim 1 , wherein the porous matrix has a mean pore diameter of less than about 15 thousands of an inch. 
     
     
         14 . A method of cooling an engine comprising:
 passing a fluid propellant coolant from a propellant tank into a cooling jacket, through a thermally conductive porous matrix occupying a channel between a fluid-impermeable inner wall and a fluid-impermeable outer shell of the cooling jacket, out of the cooling jacket, and into a combustion chamber defined by the inner wall of the cooling jacket.   
     
     
         15 . The method of  claim 14 , wherein the porous matrix includes structures providing multiple direct thermal connections between the inner wall and the outer shell. 
     
     
         16 . The method of  claim 14 , wherein the porous matrix includes structures directing mixing of the coolant fluid within the channel. 
     
     
         17 . The method of  claim 16 , wherein the porous matrix structures directing mixing of the coolant fluid include microtubes. 
     
     
         18 . The method of  claim 16 , wherein the porous matrix structures directing mixing of the coolant fluid include ribbon structures. 
     
     
         19 . The method of  claim 14 , wherein the channel is a contoured cooling chamber. 
     
     
         20 . The method of  claim 14 , wherein the porous matrix follows a contour of the channel. 
     
     
         21 . The method of  claim 14 , wherein the inner wall, the porous matrix, and the outer shell are formed from stacked and aligned metal layers of the cooling jacket. 
     
     
         22 . The method of  claim 14 , wherein the porous matrix includes one or more of a microfluidic porous lithographic structure, a microfluidic porous metal foam, and an open cell metal foam. 
     
     
         23 . The method of  claim 14 , wherein the porous matrix is non-catalytic with the coolant fluid. 
     
     
         24 . The method of  claim 14 , wherein the porous matrix includes one or more of aluminum, nickel, and stainless steel. 
     
     
         25 . The method of  claim 14 , wherein the porous matrix has a porosity of less than 80%. 
     
     
         26 . The method of  claim 14 , wherein the porous matrix has a mean pore diameter of less than about 15 thousands of an inch. 
     
     
         27 . An engine comprising:
 a combustion chamber;   a cooling jacket including:
 a fluid-impermeable inner wall defining the combustion chamber; 
 a fluid-impermeable outer shell forming a channel between the inner wall and the outer shell; and 
 a thermally conductive porous matrix occupying the channel, wherein the cooling jacket includes an inlet configured to receive a coolant fluid into the porous matrix at one end of the cooling jacket and an outlet configured to expel the coolant fluid from the porous matrix at an opposite end of the cooling jacket into the combustion chamber.