The working principle of solar water heater:
Sunlight passes through the first layer of glass of the heat-absorbing tube and shines on the black heat-absorbing layer of the second layer of glass. Solar water heater means to absorb the heat of sunlight energy. Because the two layers of glass are vacuum insulated, the heat is transferred. The heat will be greatly reduced (radiation heat transfer still exists, but there is no heat conduction and heat convection), most of the heat can only be transferred to the water in the glass tube, so that the water in the solar water heater glass tube is heated, and the heated water becomes lighter. Go up the heated surface of the glass tube and enter the thermal storage bucket. The relatively low-temperature water in the solar water heater bucket enters the glass tube along the backlight surface of the glass tube to replenish it. Such continuous circulation makes the water in the solar water heater thermal storage bucket continuous Heating to achieve the purpose of hot water.
