solar water heater
Solar water heaters to solar energy into heat, from low-temperature water heated to high temperatures, to meet people in life, the production of hot water use. Solar water heater is a collector, storage tank and related annexes, to rely mainly on solar energy conversion into heat collector tube. Collector surface by the sun high temperature, tube surface temperature is low back positive, while the tube temperature reaction of water will produce, use cold water sinking floating principles to produce micro-circulation of water to achieve the required hot water.
Solar water heater works: First, the endothermic process Solar radiation through the glass cover, is absorbed by the collector and the wall along the fin tube is passed to the heat-absorbing water. Heat-absorbing heat-absorbing water tube after the temperature increases, reducing the proportion of the rise in the formation of an upward momentum to form a thermal siphon system. As the water continues to move up and stored in the tank top, while constantly replenished through the circulation pipe under the water cooler, so the cycle, and ultimately all the water FCL increased to a certain temperature. Existing flat collector, basically using multi-barrel with a good combination of methods, such as rolling or pressing methods, which take the water pipes and the thermal resistance between the heat-absorbing plate is almost negligible. Flat plate collector of the core performance of the main factors, one structural design, the second is the surface absorption coating. Well-designed collector's board core fin efficiency should be 93%. Collector fin efficiency and the board core board core structure, surface treatment and the overall structure of the collector. The overall structure of the collector can be used to describe the overall heat transfer coefficient, and its influence with its own geometry (rib thickness, material) are the same. That is, in the case of the same efficiency, the collector plate core heat loss can be thinner hours. Selective absorption surface to increase the thermal efficiency, but to improve the economic efficiency of such products on the market, often thin fin. Occasion for the water heater when the effects of such products and selectivity actual number of collectors (not even optional), but fins thicker collector will not be much difference. Second, the circulation line Domestic solar water heaters usually work the way the natural cycle, no external power, well-designed system, as long as there is more than 5 ~ 6 Â¡ÃŠ temperature can cycle very well. Water circulation pipe diameter and pipe distribution directly affect the rationality of the heat exchange efficiency of the collector. In most cases, domestic water heater system, natural circulation flow in the pipeline can be considered as laminar flow. Collector resistance of the pipeline system along the main resistance came from, much less the impact of local resistance, which branch off than the resistance along the way charge is much greater. When the water temperature increases, due to the kinematic viscosity decreases, the resistance along the smaller, local resistance are larger. Within a certain range, when the charge diameter is constant, increasing branch diameter, the resistance along the way not only decrease rapidly, and reduce local resistance will follow. In general, the hydraulic radius of the branch should be 10mm or more. When the diameter reaches a certain value charge, an increase in charge diameter on the reduced system resistance has little significance. Third, the process of using top-water reactor The use of water for domestic solar water heaters into roof fell into the water type and water type. Fell into the water supply is not affected use, the drawback is the use of the process after the first low temperature high, if not easy to grasp water shortage caused by a sudden embarrassment. Is the temperature of the water way to the top of the first high to low, easy to grasp, easy to adapt to the user, but requires water to maintain water supply capacity. Guaranteed in the case of tap water is recommended to use the top of the water way. Domestic solar water heater designed to the top of the water mode, the internal structure of the tank must be reasonably designed to ensure uniformity of water, avoid the formation of water, "short" or dead. Designed using the pipe can be converted into the best type of connection drowning in the water deficiency or water stress during emergency use.
- Home Page