Basic understanding of fluid resistance: When the fluid flows in the 304 square tube, it will be affected by various resistances. Fluid resistance mainly includes resistance along the way and local resistance, and the impact of inner wall roughness on the resistance along the way is particularly significant. The resistance along the way is caused by the friction between the fluid and the pipe wall and the viscous friction inside the fluid.
The relationship between roughness and boundary layer: The roughness of the inner wall of the 304 square tube will change the characteristics of the fluid boundary layer. Near the pipe wall, the fluid flow rate will gradually decrease, forming a boundary layer. When the inner wall roughness is small, the boundary layer is smoother and the fluid flows relatively smoothly. When the roughness increases, the boundary layer will become unstable and more vortices and turbulence will appear, which will greatly increase the energy loss of the fluid and thereby increase the fluid resistance.
Influence under laminar flow state: In laminar flow state, the fluid flows in layers without interfering with each other. At this time, the impact of the inner wall roughness of the 304 square tube on the fluid resistance is relatively small. Fluid is mainly affected by viscous force, and the resistance is proportional to the first power of the flow rate. However, as the roughness increases, the friction of the pipe wall against the fluid will increase, which will still lead to a certain increase in resistance.
Effects of turbulent flow: In turbulent flow, the flow of fluid becomes chaotic. At this time, the impact of the inner wall roughness of the 304 square tube on the fluid resistance is extremely obvious. The vortices and turbulence caused by roughness intensify, causing a large amount of the kinetic energy of the fluid to be converted into heat energy and lost. The resistance is proportional to the square of the flow velocity, and as the roughness increases, the resistance coefficient will rise sharply, resulting in a significant increase in fluid resistance.
The impact of increased roughness on energy loss: When the roughness of the inner wall of the 304 square tube increases, more energy needs to be provided in order to maintain the same fluid flow. This means that in actual applications, more power will be consumed and operating costs will increase. For example, in an industrial water supply system, if the inner wall of a square pipe becomes rougher due to corrosion or other reasons, the water pump will need to consume more electricity to ensure water delivery.
The impact of roughness on different fluids is different: Fluids with different properties are affected by the roughness of the inner wall of the 304 square tube to varying degrees. For fluids with greater viscosity, such as crude oil, the impact of roughness on resistance is more significant. Because the flow resistance of viscous fluid itself is large, and the turbulence caused by roughness will further increase energy loss. For less viscous fluids, such as air, the impact of roughness is relatively small, but the impact cannot be ignored when flowing at high speeds.
Methods to control roughness to reduce resistance: In order to reduce the fluid resistance when the 304 square tube is used as a fluid delivery pipe, a variety of measures can be taken to control the roughness of the inner wall. For example, during the manufacturing process, high-precision processing technology is used to ensure that the inner wall is smooth. During use, the pipelines should be cleaned and maintained regularly to prevent the accumulation of dirt and corrosion and keep the inner wall clean and flat, thereby reducing fluid resistance and improving transportation efficiency.
