Strengthened transmission tubes for falling film evaporators

Abstract

The present invention discloses strengthened heat transmission tubes for falling film evaporators. The tube includes a tube body of the heat transmission tube and fins disposed on an outside surface of a heat transmission section of the tube body. The fins spirally surround the outside surface of the tube body of the heat transmission tube along an axial direction. The roots of the fins are integrally connected with the tube body. Each of the fins has a cross sectional T shape. Interspaces between two neighboring fins along the axial direction of the tube form small holes for coolants flow and evaporation, and form circular shape channels along the spiral direction. Each T shape fin has fin troughs along peripheral direction. The outer surfaces of the fins are disposed with grooves or extrusion lugs that guide coolants flow. Internal tube body is disposed with internal teeth. The present invention satisfies the characteristics of falling film evaporation, can guide coolant flow, and prevent excessive accumulation of coolants on outer walls of the heat transmission tubes. It also ensures the direction of coolants flow downwards and improves heat transmission efficiency of falling film evaporation.

1 . A strengthened heat transmission tube for falling film evaporators, comprising a tube body of the heat transmission tube and a plurality of fins disposed on an outside surface of a heat transmission section of the tube body, the fins spirally surrounding the outside surface of the tube body of the heat transmission tube along an axial direction of the tube, roots of the fins being integrally connected with the tube body; characterized in that: each of the fins has a cross sectional T shape along the axial direction of the tube; interspaces between two neighboring fins along the axial direction of the tube form small holes for coolants flow and evaporation, and form circular shape channels along the spiral direction of the fins; each T shape fin has peripheral fin troughs along peripheral direction of the tube that cut and divide the fin; outer surfaces of the fins are disposed with grooves or extrusion lugs that guide coolants flow; and internal tube body is disposed with internal teeth. 
     
     
         2 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: along the axial direction, there are 26-60 spiral T-shape fins per inch and their spiral angle is 0.3-2.5°. 
     
     
         3 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: there are 60-160 said small holes positioned along the peripheral direction of the tube; the distance between two adjacent small holes is 0.05-0.5 mm along peripheral direction; and the height of the small hole is 0.1-0.8 mm. 
     
     
         4 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: rotation direction of the grooves on the outer surface of the fins is the same as the rotation direction of the spiral fins; said grooves are connected together along the peripheral direction to form circular direction flow channels; the width of the groove is 0.05-0.5 mm; and the depth of the groove is 0.02-0.2 mm. 
     
     
         5 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: the extrusion lugs on the outer surface of the fins has an angle of 0-80° with the axial direction of the tube body of the heat transmission tubes. 
     
     
         6 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: the number of extrusion lugs on the outer surface of each fin is one or above two; the height of the lug is 0.01-0.25 mm; the width of the lug is 0.02-0.4 mm; more than two lugs are parallel to each other; and the distance between the lugs is 0.05-0.7 mm. 
     
     
         7 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: two sides of the outer surface of the T-shape fins include edge grooves or chamfers that guide the flow of the coolants. 
     
     
         8 . The strengthened heat transmission tube for falling film evaporators according to  claim 1 , characterized in that: the internal teeth within the tube bodies are in a screw thread shape; sectional shape of the screw thread shape internal teeth is close to a triangle shape; an interior angle of the internal teeth is 10-120°. 
     
     
         9 . The strengthened heat transmission tube for falling film evaporators according to  claim 8 , characterized in that: a range of the angle between the screw thread shape internal teeth and the axial direction of the tube body is 20-70°; there are 6-90 internal teeth; height of the internal teeth is 0.1-0.6 mm.