What is the structure and principle of solar water heater?
Circulation pipelineHousehold solar water heater usually according to natural circulation mode, no external power, good system design as long as there is 5~6 DEG C above the temperature will be very good. The rationality of the diameter and distribution of water circulation pipeline directly affects the heat exchange efficiency. In most cases, can be regarded as laminar flow of household water heater pipeline system in the natural circulation. Collector pipe system mainly from friction resistance, impact of local resistance is much smaller, the branch resistance is much greater than in charge. When the water temperature increases, due to the decrease of the kinematic viscosity, the resistance is smaller, and the influence of local resistance becomes larger. In a certain range, when the pipe diameter is constant, increasing the diameter of the pipe will not only reduce the resistance along the way, but also reduce the local resistance. Generally, the hydraulic radius of the branch pipe should be above 10mm. When the pipe diameter reaches a certain value, the increase of the pipe diameter has little significance to reduce the system resistance.
Two is the surface absorption coating. The core fin efficiency of the designed collector should be more than 93%. The core fin efficiency of the collector is related to the structure of the core, the surface treatment and the overall structure of the collector. The overall heat transfer coefficient of the collector can be described by the total heat transfer coefficient, which is the same as the size of the geometry. That is to say, in the case of the same efficiency, the heat collector can be thinner. Selective absorbing surface can improve the efficiency of heat collection, but these products in the market in order to improve economic efficiency, often thin rib. In the case of water heaters, the actual effect of the collection of such products and the selection of some poor (and even no selectivity) but the thickness of some of the collector will not be much difference.
The working principle of solar water heater working principle diagram: DDZ (1), a endothermic processSolar radiation through the glass cover, the water along the fin and tube wall to transfer heat tube is absorbed by the collector. When the water in the heat absorbing pipe absorbs heat, the temperature is increased, and the specific gravity is reduced to rise. With the rising of water stored in the tank top, and at the same time of low temperature of the water circulating pipe, through this way, eventually FCL water rises to a certain temperature. Plate type current collector, basically use the combination of good combination of multiple methods, such as rolling or rolling method, the thermal resistance between the pipe and the water absorbing plate can be ignored. The main factors that affect the performance of plate heat exchanger plate, the first is the structure design,
The solar water heater converts the solar energy into heat energy, and the water is heated from low temperature to high temperature, so as to satisfy the hot water use of people in life and production. The utility model relates to a solar water heater which is composed of a heat collector, a water storage tank and related accessories. The collector surface by the sunlight, high temperature, low temperature and heat nightside, produce water pipe temperature, using the principle of cold water sinking floating, the water circulation and desired hot water.
