Summary of the invention
In order to solve the problem of existing solar water heater storage water tank heat insulation effect difference, The present invention gives a kind of heat storing and heat preserving water storage device of solar water heater.
The heat storing and heat preserving water storage device of this solar water heater, comprise cylindrical shell, it is characterized in that, in the heat storing and heat preserving layer of cylindrical shell, be placed with energy storage materials of phase change, when water storage device absorbs heat, energy storage materials of phase change becomes liquid heat absorption from solid-state, when water storage device heat release, energy storage materials of phase change becomes solid-state heat release from liquid state.
Energy storage materials of phase change can be the paraffin of No. 40-No. 60, and concrete paraffin label is selected according to hot water design temperature, and it is that liquid state pours into that paraffin fills load mode.
Cylindrical shell comprises cylinder, upper cover and goes to the bottom, and cylinder comprises inner bag, heat storing and heat preserving layer and shell protective layer from the inside to the outside, and heat storing and heat preserving layer is jointly made up of energy storage materials of phase change and Conventional insulation, and it is 2 ﹕ 1 to 1 ﹕ 1 that this bi-material forms filling thickness ratio; Between energy storage materials of phase change and Conventional insulation, dividing plate is installed.
Upper cover is provided with the heat-insulation layer of 40-60mm with going to the bottom, and the insulation material of heat-insulation layer is polyurethane material.
Shell can adopt color steel, aluminium plating zinc plate or corrosion resistant plate.
Inner bag can adopt the material such as stainless steel, enamel.
Conventional insulation is mineral wool, polyurethane or various string.
According to insulation demand is selective, slim insulation film is set or/and thermal reflecting coating between energy storage materials of phase change and dividing plate.
Thermal reflecting coating is high temperature resistant, corrosion resistant type, can be aluminium film.
Slim insulation film is water proof type, and thermal conductivity factor is not higher than 0.1W/mK, and thickness is not more than 5mm, can be plastic sheeting or foaming brown paper.
Paraffin is excellent heat accumulating, and its fusing point is 57-63 ° of C, and density is 0.87-0.92, and specific heat is 2.14-2.9 J/g. degree, if melted paraffin wax heat or heat of solidification are P2, the quality of paraffin is W2, size fractal dimension B, and B is less than 1; The quality of Water in Water Tanks is W1, and specific heat of water is P1, and it is T that the water in water tank reduces temperature, then have:
T×W1 ×P1= W2× P2×B
W2/ W1=T× P1/ P2×B
Temperature T=10 ° of C is reduced with the water in water tank, B=0.9 calculates, P2 is 210 Js/g, P1=0.43 J/g. degree, the heat lost is supplemented by the melting heat of paraffin: W2/ W1=T × P1/ P2 × B=10 degree × 0.43 J/g. spend/210 Js/g × 0.9=0.023
As can be seen from above derivation, if want night the water in subsidiary water tank to reduce the heat of 10 degree, the quality of required paraffin is 2.3% of water quality.
Described energy storage materials of phase change effect is: the heat absorbing solar energy daytime, be stored in liquid energy storage materials of phase change, evening is along with the reduction of water temperature in storage tank, energy storage materials of phase change is become solid-state from liquid state, energy-accumulation material carries out phase transformation heat release, thus obviously reduces the fall off rate of water temperature in storage tank; Described thermal reflecting coating and slim insulation film, thermal reflecting coating film has the effect of reflecting heat, and the heat in inner bag and the heat in energy storage materials of phase change are then not easy outside transmission, thus reach the effect of insulation; Described slim insulation film, because its thermal conductivity factor is lower, can play insulation effect further.
The present invention can reduce storage tank and outwards distribute heat energy, and greatly improves the insulation effect of storage tank, efficient heat-insulated water tank involved in the present invention, after the period at night, the water temperature in water tank can be made to fall and remain on less than 5 DEG C.
Detailed description of the invention
Below in conjunction with accompanying drawing, further detailed description is done to embodiments of the invention:
The heat storing and heat preserving water storage device of this solar water heater, comprises cylindrical shell, in the heat storing and heat preserving layer of cylindrical shell, be placed with energy storage materials of phase change, when water storage device absorbs heat, energy storage materials of phase change becomes liquid heat absorption from solid-state, when water storage device heat release, energy storage materials of phase change becomes solid-state heat release from liquid state.Be that 60 ° of C select according to hot water design temperature, energy storage materials of phase change is the paraffin of No. 50, and it is that liquid state pours into that paraffin fills load mode.Cylindrical shell comprises cylinder, upper cover and goes to the bottom.
As Fig. 1, cylinder 12 comprises inner bag 7, energy storage materials of phase change 6 from the inside to surface successively, slim insulation film 5, thermal reflecting coating 4, dividing plate 3, polyurethane material 2 and shell 1.Inner bag 7 adopts stainless steel, and energy storage materials of phase change 6 is the paraffin of No. 50, and slim insulation film 5 is water proof type, and thermal conductivity factor is 0.05W/mK, thickness is the plastic sheeting of 1mm, and thermal reflecting coating 4 is aluminium film that is high temperature resistant, corrosion resistant type, and shell 1 adopts corrosion resistant plate.
In fig. 2, cylindrical shell comprises cylinder 12, upper cover 8 and goes to the bottom 16, upper cover 8 there is exhaust outlet 9, water supplement port 10 is arranged at cylinder 12 top, hot water outlet 13 is arranged at bottom, sewage draining exit 14 is had bottom cylinder 12, the inwall of cylinder 12 is provided with temperature and level sensor 11, the inside of cylinder 12 is provided with electric heater unit 15, upper cover 8 and 17 polyurethane insulation coatings being provided with 50mm of going to the bottom, temperature sensor and electric heater unit 15 are electrically connected, and when the water in cylindrical shell is below or above design temperature, electric heater unit 15 will start or cut out.