Heat exchanging element

Abstract

A lamination type heat exchanging element for use in heat exchange type ventilators and other air conditioning devices eliminates drift in the air passages while maintaining its structural strength, thereby providing high heat exchange efficiency. The heat exchanging element also prevents airflow leakage due to peeling between heat exchanger plates and other components. To achieve this, rectification portions are provided which eliminate drift in the air passages due to different ventilation resistances of the flow channels caused by their different flow channel lengths generated by flow channel division portions, thereby forming a predetermined flow velocity distribution in the counterflow regions.

1 . A heat exchanging element for performing heat exchange by circulating a primary airflow and a secondary airflow through corresponding air passages alternately formed between a plurality of heat exchanger plates laminated on each other with a predetermined spacing, the heat exchanging element comprising:
 counterflow regions in which the primary airflow and the secondary airflow flow opposite to each other with the heat exchanger plates therebetween;   shield portions for preventing airflow leakage from regions other than inlet ports and outlet ports of the primary airflow and the secondary airflow in the air passages;   flow channel division portions for dividing each of the air passages into a plurality of flow channels, the flow channels divided by the flow channel division portions having different flow channel lengths from each other; and   rectification portions arranged in the air passages, the rectification portions providing a predetermined flow velocity distribution of the primary airflow and the secondary airflow circulating through the counterflow regions in the flow channels divided by the flow channel division portions.   
   
   
       2 . The heat exchanging element of  claim 1 , wherein
 the rectification portions are located in the air passages other than the counterflow regions.   
   
   
       3 . The heat exchanging element of  claim 1 , wherein
 the rectification portions are ventilation resistance members shaped to increase ventilation resistances of flow channels other than the longest flow channel having the longest flow channel length of all the flow channels divided by the flow channel division portions.   
   
   
       4 . The heat exchanging element of  claim 3 , wherein
 the rectification portions are partially or wholly located in inlet ports of the flow channels other than the longest flow channel so that an opening area of each of the inlet ports of the flow channels other than the longest flow channel can be smaller than an opening area of an inlet port of the longest flow channel.   
   
   
       5 . The heat exchanging element of  claim 3 , wherein
 the rectification portions are partially or wholly located in outlet ports of the flow channels other than the longest flow channel so that an opening area of each of the outlet ports of the flow channels other than the longest flow channel can be smaller than an opening area of an outlet port of the longest flow channel.   
   
   
       6 . The heat exchanging element of  claim 3 , wherein
 the rectification portions are partially or wholly located in inlet ports and outlet ports of the flow channels other than the longest flow channel so that an opening area of each of the inlet ports and an opening area of each of the outlet ports of the flow channels other than the longest flow channel can be smaller than an opening area of an inlet port and an opening area of an outlet port, respectively, of the longest flow channel.   
   
   
       7 . The heat exchanging element of  claim 1 , wherein
 the rectification portions are shaped to decrease ventilation resistances of flow channels having flow channel lengths longer than an average flow channel length of the flow channels divided by the flow channel division portions and to increase ventilation resistances of flow channels having flow channel lengths shorter than the average flow channel length.   
   
   
       8 . The heat exchanging element of  claim 7 , wherein
 the rectification portions are partially or wholly located in the inlet ports of the flow channels so that an opening area of each of the inlet ports of the flow channels having longer flow channel lengths than the average flow channel length can be larger than an average opening area of the inlet ports, and that an opening area of each of the inlet ports of the flow channels having shorter flow channel lengths than the average flow channel length can be smaller than the average opening area of the inlet ports.   
   
   
       9 . The heat exchanging element of  claim 7 , wherein
 the rectification portions are partially or wholly located in the outlet ports of the flow channels so that an opening area of each of the outlet ports of the flow channels having longer flow channel lengths than the average flow channel length can be larger than an average opening area of the outlet ports, and that an opening area of each of the outlet ports of the flow channels having shorter flow channel lengths than the average flow channel length can be smaller than the average opening area of the outlet ports.   
   
   
       10 . The heat exchanging element of  claim 7 , wherein
 the rectification portions are partially or wholly located in the inlet ports and the outlet ports of the flow channels so that an opening area of each of the inlet ports and an opening area of each of the outlet ports of the flow channels having longer flow channel lengths than the average flow channel length can be larger than an average opening area of the inlet ports and an average opening area of the outlet ports, respectively, and that an opening area of each of the inlet ports and an opening area of each of the outlet ports of the flow channels having shorter flow channel lengths than the average flow channel length can be smaller than the average opening area of the inlet ports and the average opening area of the outlet ports, respectively.   
   
   
       11 . The heat exchanging element of  claim 1 , wherein
 the flow channel division portions are partially integrated with the rectification portions, and   the rectification portions are formed by bending parts of the flow channel division portions in such a manner that an opening area of flow channels having longer flow channel lengths than an average flow channel length of the flow channels divided by the flow channel division portions can be larger than an average opening area, and that an opening area of flow channels having shorter flow channel lengths than the average flow channel length can be smaller than the average opening area.   
   
   
       12 . The heat exchanging element of  claim 1 , wherein
 the rectification portions that increase ventilation resistances of the flow channels divided by the flow channel division portions are integrally formed with the flow channel division portions, the rectification portions being formed as projections on surfaces of the flow channel division portions that are in contact with the flow channels.   
   
   
       13 . The heat exchanging element of  claim 1 , wherein
 the rectification portions that increase ventilation resistances of the flow channels divided by the flow channel division portions are integrally formed with the shield portions, the rectification portions being formed as projections on some or all surfaces of the shield portions that are in contact with opening sections of the flow channels.   
   
   
       14 . The heat exchanging element of  claim 12 , wherein
 the projections are high on an opening side and low on an inner side.   
   
   
       15 . The heat exchanging element of  claim 1 , wherein
 the rectification portions that increase ventilation resistances of the flow channels divided by the flow channel division portions are formed as projections on the heat exchanger plates.   
   
   
       16 . The heat exchanging element of  claim 15 , wherein
 the projections are formed between one side surface of the heat exchanger plates and a reverse side of the flow channel division portions.   
   
   
       17 . The heat exchanging element of  claim 1 , wherein
 the heat exchanger plates are integrally molded with resin frames using an injection molding process so as to form a plurality of unit elements, the heat exchanger plates being made of paper or resin and having heat conductivity, moisture permeability, and a gas shielding property, the resin frames being made of synthetic resin and forming the air passages including the shield portions, the flow channel division portions, and the rectification portions, and the plurality of unit elements being laminated on each other.   
   
   
       18 . The heat exchanging element of  claim 1 , wherein
 the heat exchanger plates made of thermoplastic resin are each provided with an uneven surface structure so as to form the shield portions, the flow channel division portions, and the rectification portions thereon so as to form the unit elements, the unit elements being laminated on each other.   
   
   
       19 . The heat exchanging element of  claim 1 , wherein
 the primary airflow and the secondary airflow circulating the flow channels divided by the flow channel division portions are subjected to heat exchange in order of being at a right angle or an oblique angle to each other, being opposite to each other, and being at a right angle or an oblique angle to each other with the heat exchanger plates therebetween.   
   
   
       20 . The heat exchanging element of  claim 1 , wherein
 the heat exchanging element has a rectangular picture plane in a lamination direction, inlet ports of the primary airflow on a short side, inlet ports of the secondary airflow on the other short side, and outlet ports of the primary airflow and outlet ports of the secondary airflow on a long side.   
   
   
       21 . The heat exchanging element of  claim 13 , wherein
 the projections are high on an opening side and low on an inner side.