Working Principle of Solar Water Heater – Solar Water Heater Schematic
Solar energy is a steady stream of available resources, many countries and regions are vigorously promoting the use of solar technologies, including solar water heater is the most widely used solar energy as a form, let them learn what a solar water heater works, see How solar energy to generate electricity, provide us with free hot water.
Engineering principles of solar water heater is more complex, in accordance with the structure of the main points include: principles of solar water heaters, heat absorption, circulation principles, insulation principle, in accordance with the classification of solar water heater vacuum tube solar water heaters that we need to understand the working principle of the peace panel solar water heater works.
Solar water heater collector absorber theory
Collector solar water heater with a special surface coating, the coating on the visible light range of solar energy has great absorption rate, absorbed as heat after heat collector in the long wave thermal radiation wavelength range, the coating on the long waves Emission rate is very low, so that effective “retention” of the solar heat.
Solar water heater circulation principle
Density than cold water using cold water sink, hot water up to form a natural convection loop, so that the water in the tank gradually heat until the water temperature to achieve customer satisfaction. When the sun intensity insufficient to meet the cycle time of need, you can add a closed water circulation pump, to achieve forced circulation.
Principles of solar water heater insulation
Solar thermal tanks and other holding tanks, is a container for storing water. Solar water heater only during the day because of work, and people generally only use hot water at night, in order to produce hot water during the day or the next day in the evening used to maintain a certain temperature, it must store the hot water tank insulation. Holding tank has three parts: outer bulb, polyurethane foam layer and stainless steel, which, polyurethane foam layer is responsible for solar water heaters, insulation, polyurethane insulation performance, is currently the lowest thermal conductivity of all building materials (≤ 0.024), The highest thermal resistance of insulation materials. Solar water heater, the foam layer thickness is generally between 50mm-70mm, the actual thermal performance depends on the manufacturer of foam machinery, standardized tooling and process technology.
Vacuum tube solar water heater work principle
Solar water heater is all glass vacuum tube, heat preservation water tank, bracket three parts. The core component is the all-glass vacuum collector tube, which consists of two concentric circle of the special hard glass tube borosilicate composition, and the inner wall of glass vacuum coating process by magnetron sputtering coating, the coating on the sun Selective absorption of light, its absorption ratio ≥ 0.92, emission ratio ≤ 0.09 (80 ℃), with a high absorption rate and low emissivity. Vacuum tube to absorb solar radiation into heat energy, the use of water density than cold water, cold water sink, hot water up the characteristics of the formation of cold water in the vacuum tube from top to bottom, bottom of the natural water cycle The temperature of the entire water tank to gradually increase, reach a certain temperature.
Flat Solar water heater work principle
1、Endothermic process: through the glass cover of solar radiation, absorbed by the collector and the wall along the finned tube is passed to the heat-absorbing water, heat after heat-absorbing water tube temperature, reduce 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.
2、Circulation line: collector resistance within the pipe system along the main drag from. 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 pipe should be 10mm or more.
3、The process of using top-water type: 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, in the case of water supply is guaranteed, recommended way to the top of the water.
Solar water heaters are the most common form of hot water systems, we out of the room to everywhere, and are now working principle of solar water heaters are widely used, technology continues to improve, all kinds of solar water heater equipment after another to present the most widely used vacuum tubes Plate solar water heater solar water heater in terms of the peace, comfort 100 experience and user feedback, according to the installation point of view, solar water heater be more energy efficient, safe, beautiful, so we now choose the time of solar water heaters, must not seek cheap, so worth the candle.