Phase change heat storage type solar water heater

Abstract

The utility model belongs to and discloses a phase change heat storage type solar water heater which comprises a cylindrical storage tank. The heat exchange plate is horizontally arranged in an inner cavity of the storage tank and divides the storage tank into a water storage cavity and a heat exchange cavity which are arranged up and down, the water storage cavity is used for storing water, the heat exchange cavity is filled with a phase change material, and the phase change material and water abut against the two sides of the heat exchange plate correspondingly; the plurality of vacuum tubes are obliquely fixed outside the storage tank and are arranged at equal intervals; the vacuum tube communicates with the heat exchange cavity, and an inner cavity of the vacuum tube is filled with the phase-change material; the supporting frame is used for fixing the storage tank and the vacuum pipe. According to the utility model, the structure is novel, the phase-change material is combined with solar energy, and by means of the characteristics of the phase-change material, natural convection can be utilized to the greatest extent in the heat storage and release process to play a role in enhancing heat transfer, so that the storage and supply of energy are moderately adjusted, and the development and application of clean fuel are promoted, thereby achieving the purpose of saving energy.

Description

TECHNICAL FIELD

[0001] The utility model belongs to solar water heater technical field, especially relate to a phase change heat accumulation type solar water heater. BACKGROUND

[0002] Solar water heater is a kind of energy-saving and environment-friendly water heater, absorbs the radiant heat energy of sun, heats cold water and provides for people in life, production;Now common solar water heater is vacuum tube type water heater, mainly relies on vacuum tube to collect solar radiation, heats the water in vacuum tube, then relies on the cold and hot difference of water to form a natural circulation process, ensure that the water temperature in storage tank rises continuously.

[0003] But the existing vacuum tube type solar water heater is directly used in water in vacuum tube, as direct heat storage medium, its heat storage density is low, and water temperature cannot be effectively maintained at night or rainy day, and water may appear pipe burst phenomenon at high temperature in summer, and safety is insufficient;At the same time, water is heated directly in vacuum tube, and scale is accumulated in the vacuum tube, which causes the volume of the vacuum tube to gradually decrease, and the scale is not easy to clean, which affects use, and the accumulation of scale also affects heat transfer, reduces the utilization rate of solar energy of water in vacuum tube, and limits the popularization and application of vacuum tube water heater.

[0004] Therefore, the present application designs a phase change heat accumulation type solar water heater to solve the above technical problems. CONTENT OF UTILITY MODEL

[0005] To solve the above technical problems, the utility model provides a phase change heat accumulation type solar water heater.

[0006] To achieve the above purpose, the utility model provides a phase change heat accumulation type solar water heater, which comprises:

[0007] Storage tank, the storage tank is cylindrically arranged, and is used for storing water;

[0008] Heat exchange plate, the heat exchange plate is horizontally arranged in the inner cavity of the storage tank, the heat exchange plate divides the storage tank into water storage cavity and heat exchange cavity arranged above and below, the water storage cavity is used for storing water, the heat exchange cavity is filled with phase change material, and the phase change material and water respectively abut the two sides of the heat exchange plate;

[0009] A plurality of vacuum tubes, a plurality of the vacuum tubes are fixedly inclined on the outside of the storage tank, and a plurality of the vacuum tubes are arranged at equal intervals;The vacuum tube is communicated with the heat exchange cavity, and the phase change material fills the inner cavity of the vacuum tube;

[0010] Support frame, the support frame is used for fixing the storage tank and the vacuum tube.

[0011] Preferably, the inclination angle of the vacuum tube is 45° downward.

[0012] Preferably, the vacuum tube comprises an inner tube and an outer tube coaxially arranged, a gap is arranged between the inner tube and the outer tube and is vacuumized, and the phase change material is filled in the inner cavity of the inner tube.

[0013] Preferably, the end of the inner tube is provided with a connecting head, the outer wall of the storage tank is provided with a connecting seat in communication with the heat exchange cavity, and the connecting head is threadedly connected to the connecting seat.

[0014] Preferably, the outer wall of the inner tube is coated with a heat absorption layer.

[0015] Preferably, the phase change material comprises paraffin.

[0016] Preferably, the outer wall of the storage tank is provided with a heat preservation layer.

[0017] Preferably, the support frame comprises a plurality of support rings arranged outside the storage tank, support rods are arranged on the support rings, and support seats are arranged between the support rods.

[0018] Preferably, the side wall of the support seat is provided with a side frame, a plurality of positioning grooves corresponding to the vacuum tubes are arranged on the side frame, and the bottom end of the vacuum tube abuts against the positioning groove.

[0019] Compared with the prior art, the phase change heat storage type solar water heater has the advantages and technical effects that: the phase change heat storage type solar water heater is novel in structure, combines the phase change material with the solar energy, and utilizes the natural convection to strengthen heat transfer in the heat storage and release process by means of the characteristics of the phase change material, thereby moderating the energy storage and supply, promoting the development and application of clean fuel, and achieving the purpose of energy saving.

[0020] The phase change heat storage type solar water heater is novel in structure, combines the phase change material with the solar energy, and utilizes the natural convection to strengthen heat transfer in the heat storage and release process by means of the characteristics of the phase change material, thereby moderating the energy storage and supply, promoting the development and application of clean fuel, and achieving the purpose of energy saving. BRIEF DESCRIPTION OF DRAWINGS

[0021] The drawings constituting a part of this application are used to provide further understanding of the application, and the illustrative embodiments of the application and the description thereof are used to explain the application, and do not constitute improper limitation on the application.

[0022] Figure 1 It is a perspective view of the phase change heat storage type solar water heater of the utility model;

[0023] Figure 2The utility model discloses a phase change heat accumulation type solar water heater side view structure schematic diagram.

[0024] Figure 3 The utility model discloses Figure 2 The partial close-up view of A in the middle;

[0025] Figure 4 The utility model discloses phase change material paraffin melting process liquid phase rate curve;

[0026] Figure 5 The utility model discloses phase change heat accumulation type solar water heater heat accumulation process temperature field;

[0027] Figure 6 The utility model discloses phase change heat accumulation type solar water heater heat accumulation process phase diagram;

[0028] Figure 7 The utility model discloses heat releasing process water temperature change curve with time;

[0029] Figure 8 The utility model discloses phase change heat accumulation type solar water heater heat releasing process temperature field;

[0030] In the drawing: 1, storage tank;2, heat exchange plate;3, water storage cavity;4, heat exchange cavity;5, phase change material;6, vacuum tube;7, support frame;8, inner tube;9, outer tube;10, connecting head;11, connecting seat;12, heat absorption layer;13, heat preservation layer;14, support ring;15, support rod;16, support seat;17, side frame;18, positioning groove. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the utility model will be described clearly and completely below with reference to the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the utility model.

[0032] In order to make the above-mentioned purpose, features and advantages of the utility model more obvious and easy to understand, the utility model will be further described in detail below with reference to the drawings and specific embodiments.

[0033] Referring to Figures 1-8 The utility model discloses a phase change heat accumulation type solar water heater, including:

[0034] Storage tank 1, storage tank 1 is cylindrically arranged, is used to store water;

[0035] The heat exchange plate 2 is horizontally arranged in the inner cavity of the storage tank 1, the heat exchange plate 2 divides the storage tank 1 into the water storage cavity 3 and the heat exchange cavity 4 arranged in upper and lower positions, the water storage cavity 3 is used for storing water, the heat exchange cavity 4 is filled with the phase change material 5, and the phase change material 5 and the water respectively abut against two sides of the heat exchange plate 2;

[0036] A plurality of vacuum tubes 6 are fixedly arranged outside the storage tank 1 in an inclined manner, the plurality of vacuum tubes 6 are arranged at equal intervals; the vacuum tubes 6 are communicated with the heat exchange cavity 4, and the phase change material 5 fills the inner cavities of the vacuum tubes 6;

[0037] A support frame 7 is used for fixing the storage tank 1 and the vacuum tubes 6.

[0038] The utility model discloses a phase change heat accumulation type solar water heater, is divided into the water storage cavity 3 and the heat exchange cavity 4 of upper and lower arrangement through the heat exchange plate 2 in the storage tank 1, stores water in the water storage cavity 3, and fills the phase change material 5 as heat transfer medium in the heat exchange cavity 4, and the phase change material 5 absorbs heat and produces phase change, stores heat, and the heat storage density is increased, not only let solar waste heat is more long -term storage in water heater, also reduced equipment volume, is convenient for arrangement installation, and the heat storage of phase change material 5 mainly relies on phase change, and the temperature change range is low, and the heat loss is little in the heat transfer process, and the expansion volume is also small, reduces the pressure requirement of equipment, improves the safety of equipment operation, also can reduce the cost of equipment, is convenient for the popularization of later period, the vacuum tube 6 is inclined to set up and is communicated with the heat exchange cavity 4, improves the ability of vacuum tube 6 and the natural convection ability of phase change material 5 to accept solar radiation, the vacuum tube 6 and the heat exchange cavity 4 form the closed system, and only the phase change material 5 exists in the inside, does not contact with outside water source, solves the problem that the scale is accumulated universally in traditional solar water heater, reduces the influence of water quality on thermal performance while greatly reducing the maintenance cost of water heater in later period, when using the water heater, in the process of heat storage, the phase change material 5 in the vacuum tube 6 accepts solar radiation, and the heated portion starts to melt due to uneven heating, and the phase change material 5 after melting will flow upwards into the heat exchange cavity 4 due to low density, and after contacting with the heat exchange plate 2, convection heat exchange with the water in the water storage cavity 3, the heat is transferred to the water to make the water reach the required temperature, and the phase change material 5 cools down due to the loss of heat, and the density increases, and flows downwards, and the subsequent phase change material 5 repeats the process, and continuously transfers the absorbed heat energy to the water in the water tank, and completes the process of heat collection scheme, in summary, the phase change material 5 has great utilization value in energy storage, and combining the phase change material 5 with the solar collector, the phase change heat accumulation type solar water heater realizes peak shaving in time and intensity between energy supply and demand in the system, improves the utilization rate of solar energy, the clean energy, and achieves the purpose of energy saving and emission reduction.

[0039] In an embodiment of the present application, the phase change material 5 is selected to have solid-liquid phase change characteristics.

[0040] Further optimization scheme, the inclination angle of vacuum tube 6 is 45 degrees to the oblique downward, the vacuum tube 6 pipe face is provided with 45 degrees angle between horizontal ground, improves the radiation of vacuum tube 6 to accept sunlight, improves the amount of solar energy absorption in unit time, and the phase change material 5 in the vacuum tube 6 arranged at 45 degrees is changed in phase change when heated, and the density changes, and then natural convection is easily formed, and phase change material 5 can be driven to flow without additional power, which is convenient for heat exchange.

[0041] Further optimization scheme, the vacuum tube 6 includes coaxially arranged inner tube 8 and outer tube 9, the gap between the inner tube 8 and the outer tube 9 is arranged and vacuumized; The phase change material 5 is filled in the inner cavity of the inner tube 8. In this embodiment, the inner tube 8 and the outer tube 9 are sealed away from the storage tank 1, the outer tube 9 is a glass tube which does not affect the penetration of sunlight, the inner tube 8 is a copper tube with high heat exchange efficiency, the two tubes are vacuumized, which reduces the heat loss, and the vacuum also reduces the oxidation efficiency of the copper tube; The phase change material 5 is filled in the inner tube 8, the heat of sunlight is transmitted to the phase change material 5 through the copper tube of the inner tube 8, and the heat is absorbed and stored by the phase change material 5; When the solid phase change material 5 absorbs heat and melts, the temperature of the liquid rises, the density becomes smaller, and then flows upward along the inner tube 8 into the heat exchange cavity 4, and transmits heat to the water in the water outlet cavity, thereby producing hot water.

[0042] Further optimization scheme, the end of the inner tube 8 is provided with a connecting head 10, the outer wall of the storage tank 1 is provided with a connecting seat 11 communicating with the heat exchange cavity 4, and the connecting head 10 is connected with the connecting seat 11 by screw connection. The connecting head 10 is arranged at the high end of the vacuum tube 6 and connected to the connecting seat 11 by screw connection, which is convenient for assembly and disassembly and maintenance.

[0043] Further optimization scheme, the outer wall of the inner tube 8 is coated with a heat absorbing layer 12. The heat absorbing layer 12 is selected to have a black coating with light absorption effect, which further improves the heat absorbing efficiency of the inner tube 8 and improves the utilization rate of sunlight; At the same time, the heat absorbing layer 12 is arranged outside the inner tube 8, which is protected by the outer tube 9 and vacuum, reducing the damage to the heat absorbing layer 12 caused by wind, sun or scratching, prolonging the service life.

[0044] Further optimization scheme, the phase change material 5 includes paraffin. The phase change material 5 of this embodiment selects paraffin, which is a mixture of hydrocarbons with a melting point of 47-64℃ depending on the composition, and the chemical properties of paraffin are stable at room temperature and are not easy to react with other substances; At the same time, paraffin has certain thermal stability and can withstand temperature changes within a certain range without significant deformation or damage; Paraffin also has certain thermal conductivity and can transfer heat, so it can be used as the phase change material 5 of this embodiment.

[0045] Further optimization scheme, the outer wall of the storage tank 1 is provided with a heat preservation layer 13. The heat preservation layer 13 outside the storage tank 1 can isolate the storage tank 1 from the external environment to a certain extent, reduce the damage of wind, sun and the like to the storage tank 1, and prolong the service life of the equipment; At the same time, the design of the heat preservation layer 13 can also improve the heat preservation capacity of the storage tank 1, reduce the heat loss of the hot water in the storage cavity 3 and the phase change material 5 in the heat exchange cavity 4, and improve the utilization rate of heat.

[0046] Further optimization scheme, support frame 7 includes a number of sets in the storage tank 1 outside the support ring 14, the support ring 14 is provided with support rod 15, a plurality of support rod 15 is provided with support seat 16. In this embodiment, two support ring 14 hoop in the storage tank 1 both ends, fixed in support seat 16 through two support rod 15, convenient to fix the storage tank 1 on the roof, avoid being blown down in use, in use, through bolt or other fixed parts will be fixed in support seat 16 on the roof, keep stable.

[0047] Further optimization scheme, the side wall of support seat 16 is provided with side frame 17, the side frame 17 is provided with a plurality of positioning groove 18 corresponding to the vacuum tube 6, the bottom end of vacuum tube 6 abuts in the positioning groove 18. Side frame 17 is fixed on the support frame 7, the positioning groove 18 on it is arranged correspondingly with the vacuum tube 6, used for supporting the bottom end of the vacuum tube 6, plays a fixed role.

[0048] The principle and design process of the device

[0049] I. Using paraffin as phase change material, design simulation model:

[0050] The enthalpy-porosity model is used to describe the physical process of the phase boundary flow along time evolution in the fixed grid method. This method determines the liquid phase proportion of the control volume through enthalpy balance calculation, and the position of the phase boundary change is indirectly obtained by tracking the liquid part. For the mathematical description of the melting / solidification process, the following necessary simplifications are made:

[0051] (1) The thermal physical properties of paraffin are constant.

[0052] (2) Boussinesq assumption is used, i.e. the density change caused by pressure is ignored, and the density change caused by temperature is considered, and the liquid density change only appears in the buoyancy source term.

[0053] (3) Viscous dissipation can be ignored.

[0054] (4) Liquid paraffin is a Newtonian fluid and is incompressible. The flow of fluid is controlled by continuity, momentum and energy equations.

[0055] Continuity equation:

[0056]

[0057] Momentum equation:

[0058]

[0059] Energy equation:

[0060]

[0061] Where, u, v, w are velocity components in x, y and z directions, respectively; p is the density of paraffin; c is the specific heat capacity; P is the pressure; μ is the dynamic viscosity; k eff is the effective thermal conductivity; g is the acceleration of gravity; T is the temperature; T0 is the reference temperature; β is the volume expansion coefficient; L is the latent heat of phase change; f is the liquid volume fraction, and the buoyancy effect is included in the source term S z

[0062] Table 1, numerical simulation of paraffin and water physical property parameters

[0063]

[0064] II. Device design

[0065] Considering the acceptance of solar radiation and natural convection, the angle between the vacuum tube 6 and the ground is selected as 45° to strengthen the heat transfer process; paraffin is used as the phase change material 5 instead of water to improve the heat storage density. In the case of meeting the daily large flow use, the water tank capacity is appropriately reduced. The total capacity of the storage tank 1 is 80L; the volume of the water storage cavity 3 is 60L; the volume of the heat exchange cavity 4 is 20L, the heat transfer plate is 2.5mm thick copper plate; the number of vacuum tubes 6 is 10; the inner diameter of the vacuum tube 6 is 5.8×10-2m; the length of the vacuum tube 6 is 1.6m; the storage capacity of a single vacuum tube 6 is 4.227×10-3m3; the total volume of the heat storage material paraffin that can be filled is 6.227×10-2m3; the latent heat of phase change is 12329.46KJ; therefore, when the temperature difference of water is set to 25℃, 117L of water can be heated.

[0066] III. Analysis of simulation results

[0067] Heat absorption process:

[0068] Reference Figure 5 The temperature field of the heat storage process is shown. In the winter use environment, the initial temperature of the paraffin in the heat exchange cavity 4 and the water in the water storage cavity 3 is set to 278K, and the temperature of the vacuum tube 6 after heating is approximately identified as 385K. The temperature situation is represented by different colors, and the temperature field changes are recorded at 250s, 500s, 1500s, 2500s, 3500s and 4500s. Observe Figure 5 ​At 250s, the temperature of the paraffin in the vacuum tube 6 starts to rise, and the temperature on the irradiation side is higher; as the heat storage process proceeds, at 1500s, the paraffin starts to transfer heat to the upper part, at 2500s, the paraffin has been basically melted, at 3500s, the paraffin at the interface is melted, the liquid paraffin starts to flow due to the difference in density, and at the same time, the water in the storage tank 1 is heated through the heat exchange plate 2, at 4500s, the temperature of most of the water has reached 320K, and due to the difference in density caused by the water temperature, natural convection exists in the water body, the water with higher temperature moves upward to receive heat from the heat exchange plate 2, and the water with lower temperature moves to the heat exchange plate to receive heat.

[0069] Referring to Figure 6 As shown in the heat storage process phase diagram, the phase change process is represented by color change, blue represents solid state, red represents liquid state, and the rest represents melting state, and the states are recorded at 500s, 1000s, 1500s, 2000s, 3500s, 4500s, 5500s, and 6500s. It is observed that due to the uneven received solar radiation, at about 500s, the paraffin with higher temperature moves upward, and as the heat storage process proceeds, the paraffin further melts, and the convection effect in the paraffin is enhanced, at 2000s, most of the paraffin is melted, at 3500s, the interface between the vacuum tube 6 and the storage tank 1 is melted, and the lower part of the storage tank 1 starts to flow to heat the water in the water tank, at 4500s, the paraffin at the bottom is melted.

[0070] Referring to Figure 4 As shown in the paraffin melting process liquid phase rate curve, the data of the liquid phase rate is recorded from 0 to 8000s, the melting of paraffin is essentially a heat conduction process, as the melting increases, the convection effect is enhanced, and the melting rate rises, at 2000s, the paraffin is basically melted, and the melting rate has a relatively obvious decrease, at 3500s, due to the melting of the interface, the paraffin in the storage tank 1 starts to melt, the convection effect is enhanced, and the melting rate slightly rises, and then the temperature difference in the paraffin decreases, and the melting rate gradually decreases due to heat conduction to the water body.

[0071] Heat release process:

[0072] Referring to Figure 8 As shown in the heat release process temperature field, after the heat storage of the paraffin, the paraffin starts to release heat to the water under the action of natural convection. For the intermittent water supply occasions with small water flow such as daily dish washing, the paraffin mainly plays a role of heat preservation and heating, which can maintain the water temperature above 60℃. For the one-time large water use such as bathing, the water temperature will be reduced to a lower level, and the phase change material 5 is needed to heat the water, the experimental simulation conditions are that the initial water temperature is 293K and the paraffin temperature is 340K, the temperature difference on both sides of the heat exchange plate 2 can be maintained in a relatively stable state due to the natural convection of water and paraffin, and for the heat release process, the water temperature is relatively uniform.

[0073] Reference Figure 7 The water temperature change curve of the heat release process shows that, for the slope of the curve, the slope gradually decreases with the decrease of the heat transfer temperature difference, but the decrease is not much, the heat release process is relatively stable, and the average water temperature reaches 40 DEG C after about one and a half hours, and the heat release process is completed.

[0074] The innovation points and applications of the utility model are as follows:

[0075] The phase change material 5 has great utilization value in energy storage, and is combined with the solar heat collector, so that the phase change heat storage type solar water heater realizes peak load shifting of both energy supply and demand in time and intensity in the system, improves the utilization rate of the clean energy solar energy, and achieves the purpose of energy saving and emission reduction.

[0076] 1. The phase change heat storage type solar water heater has the following innovation points:

[0077] (1) The traditional water heat transfer medium is changed to the phase change as the heat transfer medium, the heat storage density is increased, the solar waste heat is stored in the water heater for a longer time, and the equipment volume is reduced, and the arrangement and installation are facilitated.

[0078] (2) Because of the closed system, the scale problem commonly existing in the traditional solar water heater is solved, the influence of water quality on the heat performance is reduced, and the maintenance cost of the water heater in the later period is greatly reduced.

[0079] (3) The vacuum tube 6 is used to load the medium phase change material 5, so that there is no freezing danger even in winter.

[0080] (4) The heat storage temperature is low, the heat loss is small in the heat transfer process, and the expansion volume is small, which reduces the pressure requirement of the equipment, makes the equipment run more safely, reduces the cost of the equipment, and facilitates the later popularization.

[0081] 2. Application prospect of the phase change heat storage type solar water heater device:

[0082] (1) Solar energy itself as a clean and renewable energy source has been widely recognized and applied by the society, and the device structure is simple, convenient to install, and the phase change heat storage type solar water heater device will have great market space.

[0083] (2) The device can provide users with temperature-stable hot water for 24 hours, compared with the common electric water heater or gas water heater on the market, the phase change heat storage solar water heater can greatly reduce the consumption of electricity and the emission of combustion waste gas after being put into use, and has strong competitiveness.

[0084] In the description of the utility model, need understanding is, the term "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and so on indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawing, just for the convenience of describing the utility model, and it is not indicated or implied that the indicated device or element must have a particular orientation, a particular orientation and operation, so it can not be understood as a limitation on the utility model.

[0085] The above-described embodiments are merely preferred modes of the utility model, and do not limit the scope of the utility model, and various modifications and improvements to the technical solutions of the utility model made by those skilled in the art without departing from the design spirit of the utility model shall fall within the protection scope defined by the claims of the utility model.

Claims

1. A phase change heat accumulation type solar water heater, characterized by, The utility model relates to a kind of water storage device, including: Storage tank (1), the storage tank (1) is cylindrical, for storing water; Heat exchange plate (2), the heat exchange plate (2) is arranged in the inner cavity of the storage tank (1), the heat exchange plate (2) is divided into water storage cavity (3) and heat exchange cavity (4) arranged in upper and lower, the water storage cavity (3) is used for storing water, the heat exchange cavity (4) is filled with phase change material (5), the phase change material (5) and water are respectively with the abutment of both sides of the heat exchange plate (2); Several vacuum tubes (6), several the vacuum tube (6) is fixedly inclined in the storage tank (1) outside, several the vacuum tube (6) is arranged at equal intervals;The vacuum tube (6) is communicated with the heat exchange cavity (4), and the phase change material (5) fills the inner cavity of the vacuum tube (6); Support frame (7), the support frame (7) is used to fix the storage tank (1) and the vacuum tube (6).

2. The phase change heat accumulation type solar water heater according to claim 1, characterized in that: The inclination angle of the vacuum tube (6) is 45 degrees downward.

3. The phase change heat accumulation type solar water heater according to claim 1, characterized in that: The vacuum tube (6) includes coaxially arranged inner tube (8) and outer tube (9), and the gap between the inner tube (8) and the outer tube (9) is arranged and vacuumized;The phase change material (5) is filled in the inner cavity of the inner tube (8).

4. The phase change heat accumulation type solar water heater according to claim 3, characterized in that: The end of the inner tube (8) is provided with a connecting head (10), and the outer wall of the storage tank (1) is provided with a connecting seat (11) communicated with the heat exchange cavity (4), and the connecting head (10) is screwed on the connecting seat (11).

5. The phase change heat accumulation type solar water heater according to claim 3, characterized in that: The outer wall of the inner tube (8) is coated with a heat-absorbing layer (12).

6. The phase change heat accumulation type solar water heater according to claim 1, characterized in that: The phase change material (5) includes paraffin.

7. The phase change heat accumulation type solar water heater according to claim 1, characterized in that: The outer wall of the storage tank (1) is provided with a heat preservation layer (13).

8. The phase change heat accumulation type solar water heater according to claim 1, characterized in that: The support frame (7) includes a plurality of support rings (14) sleeved on the outer wall of the storage tank (1), a plurality of support rods (15) are arranged on the support rings (14), and a plurality of support seats (16) are arranged between the support rods (15).

9. The phase change heat accumulation type solar water heater according to claim 8, characterized in that: The side wall of the support seat (16) is provided with a side frame (17), and a plurality of positioning grooves (18) corresponding to the vacuum tubes (6) are arranged on the side frame (17), and the bottom end of the vacuum tube (6) abuts in the positioning groove (18).

Images