Patent ID: 6868695

Claim:
A falling film evaporator through which a refrigerant is conveyed, the falling film evaporator comprising: a shell defining an evaporator inlet and an evaporator outlet, the shell having a longitudinal length and a lateral width; a tube bundle inside the shell; and a distributor disposed above the tube bundle and being in fluid communication with the evaporator inlet and the evaporator outlet, the distributor including an inlet duct, an upper plate underneath the inlet duct, an intermediate plate underneath the upper plate and a lower plate underneath the intermediate plate, the inlet duct and the upper plate defining a first chamber therebetween that is in fluid communication with the evaporator inlet, the upper plate and the intermediate plate defining a second chamber therebetween, the intermediate plate and the lower plate defining a third chamber therebetween, the upper plate further defining a plurality of upper plate openings that place the first chamber in fluid communication with the second chamber, the intermediate plate further defining a plurality of intermediate plate openings that place the second chamber in fluid communication with the third chamber and the lower plate defining a plurality of lower plate openings so that the refrigerant from the evaporator inlet flows sequentially through the first chamber, through the plurality of upper plate openings, through the second chamber, through the plurality of intermediate plate openings, through the third chamber, through the plurality of lower plate openings, and then onto the tube bundle, the intermediate plate having an upwardly facing surface at least seventy-five percent of which is exposed to the refrigerant to permit substantially unobstructed horizontal flow across at least seventy-five percent of the upwardly facing surface.