Will the performance of the heat pipe radiator decay over time?
The cooling system based on liqud cooling has now surpassed air cooling in absolute performance, but it is the opposite in terms of service life. In case of split liquid cooling, it is necessary to regularly add liquid cooling liquid (evaporation reduction), replace liquid cooling liquid (deterioration or deposition of impurities after long-term use of chemical reaction) or replace aging sealing rubber rings;
Although the finished integrated liquid cooling is much simpler, it is not once and for all. The seemingly completely sealed waterway system still volatilizes a small amount every year, resulting in a decline in performance. At the same time, there is also an oxidation reaction between liquid and metal materials in the waterway, resulting in a decline in performance. Therefore, the integrated water cooling of various brands also has a clear warranty period. If there is a fault, it usually exceeds the warranty period.
Therefore, for many high-end players, the seemingly traditional heatpipe air cooling is still a solution with high reliability, high cost performance and low maintenance frequency. After all, the simpler the principle, the lower the failure rate of the product.
Heatpipe working principle:
Heat pipe is a kind of cooling technology that uses the property of absorbing / emitting heat in the process of phase change. The following shows the animation of the heat pipe in operation. The heat enters the heat pipe (evaporation section) from the left, and the heat is released again (condenser section) on the right. Red is the steam flow after vaporization, and blue is the liquid flowing back through the capillary structure after condensation.
It can be seen that even such a simple principle is composed of a variety of material structures. A small amount of liquid in the heat pipe has become a key part of the whole heat conduction process. In principle, it will gradually decay over time.
① Generation of non condensable gas: due to the chemical reaction or electrochemical reaction between the working liquid and the shell material, non condensable gas is generated. When the heat pipe works, the gas is swept by the steam flow to the condensation section and gathered to form a gas plug, so as to reduce the effective condensation area, increase the thermal resistance and deteriorate the heat transfer performance. The most typical example of this incompatibility is carbon steel water heat pipe. Due to the following chemical reaction between iron and water in carbon steel, the non condensable hydrogen produced will deteriorate the performance of heat pipe, reduce the heat transfer capacity and even fail.
② Deterioration of physical properties of working fluid: the organic working medium will decompose gradually at a certain temperature, which is mainly due to the unstable nature of the organic working fluid or the chemical reaction with the shell material, which makes the working medium change its
③ Corrosion and dissolution of tube and shell materials: the working liquid flows continuously in the tube and shell. At the same time, there are factors such as temperature difference and impurities, which will dissolve and corrode the tube and shell materials, increase the flow resistance and reduce the heat transfer performance of the heat pipe. When the pipe shell is corroded, the strength will be reduced, and even the corrosion perforation of the pipe shell will be caused, resulting in the complete failure of the heat pipe. Such phenomena often occur in alkali metal high temperature heat pipes.buried properties, such as toluene, alkane, Jing and other organic working liquids, which are prone to such incompatibility.
The performance of the heat pipe heatsink will decay with time. The degree of attenuation mainly depends on the quality of the heat pipe. No matter whether the radiator is in use or eating ash, the attenuation is in progress. With the progress and improvement of radiator manufacturing process, the performance degradation degree is completely acceptable after six or seven years.
