Working Principle of Solar Water Heater

First, the heat absorption process.

The fin tube absorbs heat, transferring solar radiation through the cover glass. This radiation is absorbed by the collector and walls. The heat absorption system forms a heat siphon, reducing the rate of increase in momentum. The temperature of the heat absorption tube then rises. As water is constantly replenished through the circulating tube under cold water, the cycle continues, and ultimately, all the water in the FCL increases to a certain temperature, moving and storing in the tank top. Conventional flat-plate collectors essentially use multi-barrels, with a combination of methods such as rolling or pressing, to virtually eliminate the thermal resistance between the water pipe and the heat absorption plate. The core performance of a flat-plate collector is a key factor in its structural design, with the absorption surface coating being the most important. A well-designed collector should have a core fin efficiency of 93%. The collector fin efficiency depends on the core structure, surface treatment, and overall structure of the collector. The overall structure of the entire house can be used to explain the overall heat transfer coefficient, and its influence, along with its geometry (rib thickness, material), is the same. That is, for the same efficiency, the collector core can be thinner over time. While selecting an absorber surface can improve thermal efficiency, the market for such products often favors thinner fins. While the actual performance of a water heater depends on the product and (even if not selected) the actual performance of a poor house, there is no significant difference in the case of thick-finned collectors.

Second, Circulation Line

Domestic solar water heaters generally operate very well using natural circulation, with external power sources. A well-designed system can achieve 5-6 degrees of temperature circulating through the system. The diameter and distribution of the water circulation pipes directly affect the efficiency of the entire house's heat exchange. In most domestic water heater systems, the natural circulation flow in the pipeline can be considered laminar. The collector resistance of a pipeline system, based on the main resistance, is much larger than the resistance along the path, and the local resistance at the branch is much less affected. Due to the dynamic viscosity, as the water temperature increases and decreases, the local resistance decreases, resulting in greater resistance. When the fill diameter is constant, within a certain range, the resistance along the path decreases rapidly. Local resistance will also decrease as the branch diameter increases. Generally, the hydraulic radius of the branch should be at least 10 mm. When the fill diameter reaches a certain value, increasing the fill diameter is practically meaningless, resulting in reduced system resistance.

Third, the process of using a high-temperature reactor. Water consumption for rooftop solar water heaters is reduced by the water type and the water type. The use of the water supply is not affected. If the water supply is easily cut off, a sudden water shortage can occur. The disadvantage is that the process prioritizes high temperatures and then low temperatures. Easy to adapt to users, easy to understand, the temperature of the water method from low first to high first, but it needs water to maintain the water supply capacity. In the case of tap water, it is recommended to use the top of the water method to ensure. Domestic solar water heaters designed with the top of the water mode, the internal structure of the tank should be reasonably designed to prevent the formation of "short" or dead water, and ensure the uniformity of the water. The design using pipes can be converted into a useful classification when connected to water or water shortage stress during emergency.