Spiral Flat tube is the first proposed by the Swiss Allares company, the United States Brown Company (Houston Brown Company) after an improved heat exchanger. Because of the unique structure of the pipe, the fluid is in a spiral flow in the tube, which promotes the turbulence level.
The experimental results show that the heat transfer coefficient of the tube is usually higher than that of the ordinary tube, and it is 2-3 times more than that in the lower Reynolds number, and the heat transfer coefficient 5o% above is usually increased with the increase of Reynolds number. The manufacturing process is to flatten the tube first and then twist it into a helical shape. When the pipe is arranged by the same party, the tube bundle has no supporting parts, but the contact point of the outer helix of the outer spiral tube is supported by each other. In the tube, the spiral flow of the fluid increases its turbulent degree, and the thickness of the hysteresis inner layer as the main heat resistance of heat transfer is reduced, which strengthens the heat transfer in the tube. In the shell, because the flow channel between the spiral tube is also helical, the fluid in the course of movement by centrifugal force to change the speed and direction periodically, thus strengthening the longitudinal mixing of the fluid. In addition, the fluid passes through the spiral contact point of the adjacent pipe to form the tail flow from the pipe wall, enhances the turbulent degree of the fluid itself, destroys the heat transfer boundary layer of the fluid on the pipe wall, and thus makes the heat transfer of the shell process strengthened.
Tube, heat transfer at the same time strengthen the results, so that the heat transfer effect than the ordinary shell-and-tube heat exchanger has greatly improved, especially on the fluid viscosity, one or both sides of the flow of stagnant heat transfer process, the effect is particularly prominent. 2007 Qinhuangdao Tong Lida Company developed a spiral flat tube cold forming machine and by the National invention patent, this equipment to solve the high efficiency heat exchanger components-spiral flat tube can not achieve the problem of mass production, for domestic and foreign initiative, the patent for our development of efficient energy-saving heat exchangers laid the foundation.