What are the factors that affect the heat transfer value of the air cooler?

Due to the reverse movement of the steam and liquid film in the air cooler, heat exchanger heat pipes with heat transfer value are produced. Generally, the greater the axial heat flux density, the greater the axial steam velocity, and the interfacial shear calorific value is prone to occur. Therefore, the heat transfer value is also the axial heat flux density of the gravity heat pipe.
In this case, the cryogenic heat pipe still works normally in the early stages of the attack, but as the load increases, the amount of liquid in the condensing section increases, and the radial heat transfer resistance increases. When the amount of liquid is added to the corresponding amount, the liquid overcomes the resistance of the vapor flow under the action of gravity and falls to the transpiration section.
When the warm current density is further increased to a specific value, the higher shear stress hinders and forces the return liquid to block or reverse, and the corresponding warm current is called the carrying heat transfer value. Once the warm current reaches the heat transfer value, it will cause the sweating section of the pipe wall to dry up partially, the temperature of the pipe wall rises sharply, and the pipe wall overheats or burns.
The upper limit of gravity heat pipe operation is mainly affected by the filling rate, warm current density and several scales. small filling rate, upper limit of main dryness; When the filling rate and radial heat flux density are large, and the axial heat flux density is small, the upper limit of combustion occurs. When the liquid filling rate and axial heat flux density are large, and the radial heat flux density is small, the air cooler starts with a heat transfer value.
Therefore, in order to ensure the normal operation of the air cooler, we should choose a relatively long heat exchanger. In general, the density of the axial warm current is large, while the density of the radial warm current is small, and the liquid filling rate is relatively large. In this case, the upper limit of the load heat transfer often becomes an important issue to consider when planning gravity heat pipes.