Spiral heat exchanger consists of one or more helically wound tubes arranged in a shell. It is characterized by a compact structure, larger heat transfer area than straight tubes with small thermal stress, but the tubes are more difficult to clean and can be used for heating or cooling high viscosity fluids. By guiding the fluid flow in the tubes, the spiral grooves near the wall of the fluid tank cyclone separator help reduce the thickness of the boundary layer; when a portion of the fluid flows axially along the wall, they protrude through the axis of the spiral groove in the vortex, causing boundary layer and fluid disturbance in the boundary layer. This accelerates the boiling and condensation heat transfer from the wall surface to the fluid in the spiral groove tube, which can play a significant role in enhancing heat transfer inside and outside the tube. Due to the uneven surface of the spiral groove tube, condensate is easily discharged to the surface tension tube. The condensation spiral groove tube is mainly dominated by gravity, surface tension, and viscous forces, especially on the outer surface of the tube groove. The surface tension is several times the gravitational force. When the liquid condenses on the horizontal section of the outer tube surface, the upper horizontal component pulls the condensate to the bottom, reducing the amount of condensate and thinning the film at the root of the notch. Condensation forms rapidly at the bottom of the tank due to pressure and gravity, and is quickly excluded by the tension of the circulation tube
Due to the surface tension that traps liquid condensate, each spiral groove in a spiral heat exchanger can be considered as a condensed phase motion, and the condensate in each horizontal segment (without spiral grooves) moves uniformly. Therefore, in a study of screw length, steam condensate water forms in the horizontal tube and spiral groove BCD components in sections AB and C, respectively