Pumpless absorption refrigerator using a jet

Abstract

An absorption refrigeration system using a two or more substance solution to achieve refrigeration that eliminates the need for a pump. The vapor pressure in a generator column is balanced by a pressure head of liquid solvent-solute solution. Re-dissolved solute is returned to the generator by causing some of the vapor to pass through a perforated tube or the like into the solvent where it is absorbed. At least some of the vapor is cooled to liquid solute and then expanded through an expansion valve into an evaporator to create a refrigerator. Hot vapor from the generator column can be passed through a jet to create a low pressure in the evaporator. No pump is necessary since the liquid is returned to the heating area of the generator by gravity. Closed loop control of the heating can optionally be achieved by using a pressure sensor in the rising generator column.

1 . An absorption refrigerator not requiring a pump comprising:
 a generator column with a rising portion and a descending portion, said rising portion being heated and containing vapor; said descending portion containing liquid, said liquid forming a pressure head in said descending portion, wherein said pressure head balances pressure of said vapor in said rising portion;   a jet attached to said rising portion of said generator column, wherein said vapor is jetted through said jet creating a low pressure in an evaporator, and wherein said vapor cools and liquefies to form said liquid in said descending portion   wherein at least some of said liquid is passed through an expansion device into said evaporator creating a refrigerator.   
   
   
       2 . The absorption refrigerator of  claim 1  wherein said liquid is a solution of a solute in a solvent. 
   
   
       3 . The absorption refrigerator of  claim 1  wherein said vapor is ammonia. 
   
   
       4 . The absorption refrigerator of  claim 2  wherein said solvent is water. 
   
   
       5 . The absorption refrigerator of  claim 2  wherein said solute is ammonia. 
   
   
       6 . The absorption refrigerator of  claim 2  further comprising an absorption section where said solute re-dissolves in said solvent. 
   
   
       7 . The absorption refrigerator of  claim 6  wherein said absorption section includes a perforated tube. 
   
   
       8 . The absorption refrigerator of  claim 1  further comprising closed loop control of pressure in said rising portion using a pressure sensor in said rising section controlling a heat source. 
   
   
       9 . An absorption refrigerator requiring no pump that uses a solution of a solute and a solvent, said solute having a boiling point lower than that of said solvent comprising:
 a generator with a heated vapor-containing portion and a liquid containing portion, said liquid-containing portion forming a pressure head that balances pressure in said vapor-containing portion;   a condenser in proximity to said generator;   an absorber in proximity to said condenser;   an evaporator in proximity to said condenser;   an ejector jet coupling said generator to said condenser, wherein vapor in said generator is jetted into said condenser causing a decrease in pressure in said evaporator, and wherein a portion of said vapor enters said absorber and is re-dissolved in said solvent, said absorber being connected to said liquid-containing portion of said generator;   and wherein another portion of said vapor condenses in said condenser forming a liquid that is passed through an expansion device into said evaporator causing a drop in temperature in said evaporator, and wherein expanded gas passes from said evaporator into said condenser.   
   
   
       10 . The absorption refrigerator of  claim 9  further comprising a check valve between said evaporator and said condenser that prevents vapor from said condenser from entering said evaporator. 
   
   
       11 . The absorption refrigerator of  claim 9  further comprising a pressure sensor in said vapor-containing part of said generator. 
   
   
       12 . The absorption refrigerator of  claim 11  wherein said pressure sensor controls a heater heating said generator. 
   
   
       13 . The absorption refrigerator of  claim 9  wherein said absorber contains a perforated tube. 
   
   
       14 . The absorption refrigerator of  claim 9  wherein said solute is ammonia. 
   
   
       15 . The absorption refrigerator of  claim 9  wherein said solvent is water. 
   
   
       16 . A method of absorption refrigeration comprising the steps of:
 heating a solute-solvent solution causing said solute to boil off vapor into a rising portion of a generator column;   jetting said vapor through a jet into a condenser, said jet causing a drop in pressure in an evaporator;   condensing said solute to a liquid in said condenser;   expanding said liquid solute through an expansion device into said evaporator;   allowing expanded solute vapor to re-enter said condenser;   causing a portion of said vapor in said condenser to enter an absorber where it re-dissolves in a column of liquid solute-solvent solution, said column of solution in a descending portion of said generator column, and wherein said column of liquid forms a pressure head that balances pressure of said vapor in said rising portion of said generator column.   
   
   
       17 . The method of  claim 16  wherein said solute is ammonia. 
   
   
       18 . The method of  claim 16  wherein said solvent is water. 
   
   
       19 . The method of  claim 16  further comprising the step of controlling heating of said generator using a pressure sensor in said rising portion of said generator. 
   
   
       20 . The method of  claim 16  further comprising using a check valve between said evaporator and said condenser to prevent solute vapor from entering said evaporator from said condenser.