CN102997740A

CN102997740A - Novel reinforced tube for boiling and heat exchange in tube

Info

Publication number: CN102997740A
Application number: CN2011102700940A
Authority: CN
Inventors: 杨伟光; 黄捷
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-09-09
Filing date: 2011-09-09
Publication date: 2013-03-27

Abstract

The invention discloses a novel reinforced tube for boiling and heat exchange in the tube and belongs to a horizontal heat exchange tube in a common cold exhaust tube evaporator and various dry evaporators in a refrigerating system. The novel reinforced tube is characterized by being provided with a smooth round tube, wherein the inner wall of the round tube is provided with asymmetric tooth-shaped low fins; and a twisted-tape-shaped insertion piece is inserted into the smooth round tube. Since the novel reinforced tube for boiling and heat exchange in the tube is a combination that the inner wall of the tube is provided with the asymmetric tooth-shaped low ribs and the twisted-tape-shaped insertion piece is arranged into the tube, during practical operation, phenomena such as local dry wall, oil sinking at the tube bottom, scale sinking and the like in an evaporating tube are effectively overcome; under same operation conditions, the heat flux density of an evaporator with the reinforced tube is obviously improved; under same refrigerating capacity, the tube material consumption can be saved by more than 30% compared with that of an evaporator with a light tube, and can be saved by more than 10% compared with that of an evaporator with a low ribbed tube; the pressure loss of the reinforced tube is basically equal to those of the light tube and the low ribbed tube; and the novel reinforced tube is not only simple in structure and convenient and reliable in use, but also obvious in social and economic benefits.

Description

A kind of enhanced tube of novel boiling in ducts heat exchange

Technical field

The present invention relates in the refrigeration system horizontal heat exchange tube in cold type pipe evaporator commonly used and the various dry evaporator, specifically a kind of enhanced tube of novel boiling in ducts heat exchange.

Background technology

The heat exchanger applications of boiling heat transfer is very extensive in the horizontal tube, such as various dry evaporators in the cold type pipe evaporator in the cold storage refrigerating system, the Refrigerated Transport refrigerating plant etc.Pipe fitting as the main heat transfer element of heat exchanger, adopt intensify heat transfer pipe, energy savings, the consumption of minimizing metal material, saving cost can reduce weight of equipment and appearance and size again effectively, therefore the development and application of efficient intensify heat transfer pipe has become a large focus of current heat exchanger development.

Show existing considerable relevant information on the current web from the interrelated data retrieval that comprises Chinese patent; And Chinese patent also has the relevant patent of multinomial enhanced tube.Such as " D type intensify heat transfer pipe " have efficient, energy-conservation, freeze the advantages such as quality is good, can replace widely used smooth heat transfer tube in the present freezer fully.But from published product and technical Analysis, the enhanced tube of simple low rib exists rib expansion heat-transfer area not enough, and the turbulivity that tube fluid flows is inadequate, Gan Bi, the heavy oil in the pipe end, the dirt etc. that sinks of localized heat transfer face may occur, further strengthen and hinder in diabatic process.

Cold-producing medium is in the flow boiling in horizontal tube heat exchange, there is following several heat transfer process: single-phase liquid heat convection, the heat exchange of underheat nucleateboiling, saturated nucleateboiling heat exchange, moist steam heat convection, scarce liquid steam heat convection, so this heat exchange is a kind of heat transfer process of complexity.Boiling heat transfer in the enhanced tube is divided into active and two kinds of passive types usually.Active augmentation of heat transfer need to consume external energy, and the passive type augmentation of heat transfer does not then need to consume external energy, is the method that the heat exchanger augmentation of heat transfer mainly adopts.

Summary of the invention

In order to overcome the deficiencies in the prior art, the objective of the invention is to provide a kind of simple in structure, the enhanced tube of the boiling in ducts heat exchange of easy to use and reliable passive type intensified heat transfer method.

The technical solution adopted for the present invention to solve the technical problems is: a kind of enhanced tube of novel boiling in ducts heat exchange, it is characterized in that: a smooth pipe is arranged, and the inwall of smooth pipe has asymmetric dentation to hang down fin, inserts the insert of twisted strip shape in the smooth pipe.

Described asymmetric dentation hangs down fin, is longitudinal fin.This fin can with an extrusion modling of parent tube.This is a kind of Advanced without cutting, has cost low, the advantage that is easy to promote.The design feature of this low fin is that rib root Area Ratio rib top area is much bigger, produces the nucleus of boiling and be conducive to the rib root; Asymmetric fin side is conducive to steam bubble and breaks away from from wall rapidly, has strengthened nucleateboiling.Simultaneously, the inned coefficient of this low rib sheet can reach more than 2.0, the heat transfer area that is multiplied, Effective Raise heat transfer efficiency.

The insert of described twisted strip shape is for having axle or shaftless flight.Flight can be one; Also can be 1～10 of different rotation direction; Can adopt the flight of uniform pitch or decreasing worm-pitch.Cold-producing medium is under the guide functions of insert, its generation is rotatablely moved and cause Secondary Flow, promote radially to mix, tube hub fluid and wall boundary layer fluid are mixed, cause a temperature relatively evenly, the apparent in view nucleus of velocity variations, near the heat exchange wall, cause simultaneously all apparent in view boundary layer regions of a temperature and velocity variations, thereby reach the effect of augmentation of heat transfer.And effectively eliminate Gan Bi, the heavy oil in the pipe end, heavy dirty phenomenon.

The invention has the beneficial effects as follows: because the present invention is a kind of enhanced tube of novel boiling in ducts heat exchange, its inside pipe wall is the combination of twisted strip shape insert in the low fin of asymmetric dentation and the pipe.In actual motion, the phenomenons such as the Local Dry wall in the evaporation tube, the heavy oil in the pipe end, heavy dirt have effectively been overcome.Under identical operating condition, the heat flow density of enhanced tube evaporimeter increases significantly, under identical refrigerating capacity, can save the tubing consumption more than 30% than the light pipe evaporimeter, can save tubing more than 10% than the low-finned tube evaporimeter, the pressure loss in the enhanced tube and light pipe and low-finned tube remain basically stable.The present invention is not only simple in structure, and is easy to use and reliable, and society and remarkable in economical benefits.

Description of drawings

Below in conjunction with drawings and Examples the present invention is conducted further description.

Fig. 1 is topology view of the present invention.

Fig. 2 is the full section view of axial arrangement of the present invention.

Fig. 3 is the zoomed-in view of Figure 1A part of the present invention.

Fig. 4 is that the insert in the pipe of the present invention is the topology view of uniform pitch spiral insert (dextrorotation).

Fig. 5 is that the insert in the pipe of the present invention is the topology view of dextrorotation, the combination of left-handed spiral insert.

Fig. 6 is that the insert in the pipe of the present invention is the topology view that axle spiral insert is arranged.

1 smooth pipe among the figure, 2 asymmetric dentations hang down fin, 3 inserts.

The specific embodiment

Embodiment 1:

A smooth pipe 1 is arranged, and the inwall of smooth pipe 1 has asymmetric dentation to hang down fin 2, the insert 3 of smooth pipe 1 interior insertion twisted strip shape.Wherein, the insert 3 in the smooth pipe 1 is dextrorotation decreasing worm-pitch spiral insert.

Claims

1. the enhanced tube of a novel boiling in ducts heat exchange, it is characterized in that: a smooth pipe is arranged, and the inwall of smooth pipe has asymmetric dentation to hang down fin, inserts the insert of twisted strip shape in the smooth pipe.

2. the enhanced tube of a kind of novel boiling in ducts heat exchange according to claim 1, it is characterized in that: described asymmetric dentation hangs down fin, is longitudinal fin; The structure of low fin is that rib root Area Ratio rib top area is large.

3. the enhanced tube of a kind of novel boiling in ducts heat exchange according to claim 1 is characterized in that: the insert of described twisted strip shape, for axle or shaftless flight are arranged; Flight has with 1～10 of rotation direction or different rotation direction; The flight that uniform pitch or decreasing worm-pitch are arranged.