WO2009025438A1

WO2009025438A1 - Heat exchange module using latent heat material and heat accumulator system incorporating the same

Info

Publication number: WO2009025438A1
Application number: PCT/KR2008/002406
Authority: WO
Inventors: Jeong-Kun Lee; Ji-Eun Oh
Original assignee: Est Co., Ltd.
Priority date: 2007-08-23
Filing date: 2008-04-28
Publication date: 2009-02-26
Also published as: KR100888760B1; KR20090020348A

Abstract

A heat exchange module includes first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe. The heat exchange module is usable as a condenser or an evaporator in a heat accumulator system.

Description

Heat Exchanger Using Latent Heat Material

Technical Field

[1] The present invention relates to a heat exchange module using a latent heat material and a heat accumulator system incorporating the same and, more particularly, to a heat exchange module provided with an internally stored latent heat material and designed to keep an environmental temperature constant by use of the heat stored in the latent heat material and a heat accumulator system incorporating the same. Background Art

[2] In recent years, a demand for air-conditioning in summer is sharply increased in keeping with the industrial development and the rise in national income. The sharp increase in the air-conditioning demand becomes a major culprit of causing inefficient operation of a power plant, one of national key industries. Therefore, there exists an increasing need for a heat accumulation type air-conditioning system that helps normalize an electric load by shifting the peak load time from the daytime to the midnight in summer.

[3] The heat accumulation type air-conditioning system refers to an air-conditioning system of the type that reduces the daytime demand for air-conditioning electric power by storing cold energy during the midnight when an electric power demand is decreased and using the stored cold energy in the daytime for an air-conditioning purpose. The heat accumulation type air-conditioning system has been developed and popularized for the primary purpose of stabilizing the national power supply and demand and normalizing the peak electric load.

[4] Fig. 1 shows a conventional storage container for storing a latent heat material. As shown in the figure, the storage container 1 is filled with a latent heat material and is of a generally cylindrical shape. The storage container 1 is made of a material exhibiting increased heat conductivity.

[5] Convexly curved surface portions 3 are formed in the opposite upper and lower ends of the storage container 1. The reason for forming the curved surface portions 3 is to prevent generation of cracks which would otherwise occur during repeated contraction and expansion of the latent heat material. The storage container 1 is provided at its upper end with a mouth through which the latent heat material is inserted into the storage container 1. A plug 5 is fitted to the mouth to hermetically seal the storage container 1. [6] However, the conventional storage container set forth above suffers from the following problems. If a plurality of the storage containers is cooled by use of a single coolant pipe, the storage containers fail to make exchange heat with the coolant pipe in an efficient manner. This imposes restriction on the application of the storage containers. Furthermore, the conventional storage container has a limit in storing the heat or cold energy released from a cooling system and assisting the cooling system in performing its task. Disclosure of Invention Technical Problem

[7] In view of the afore-mentioned problems inherent in the related art, it is an object of the present invention to provide a heat exchange module using a latent heat material capable of making heat exchange with a coolant pipe with increased efficiency and a heat accumulator system incorporating the same. Technical Solution

[8] According to one aspect of the present invention, there is provided a heat exchange module including first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe.

[9] In the heat exchange module noted above, each of the first and second module bodies may include a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[10] In the heat exchange module noted above, the curved outer surface portion may be provided with a corrugated surface.

[11] According to another aspect of the present invention, there is provided a heat accumulator system including: a compressor for compressing coolant; an evaporator connected to the compressor for evaporating the coolant compressed by the compressor, the evaporator comprising a plurality of heat exchange modules, wherein each of the heat exchange modules includes first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe; and a condenser for condensing the coolant evaporated by the evaporator.

[12] In the heat accumulator system noted above, each of the first and second module bodies includes a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[13] In the heat accumulator system noted above, the curved outer surface portion may be provided with a corrugated surface.

[14] According to a further aspect of the present invention, there is provided a heat accumulator system including: a compressor for compressing coolant; an evaporator connected to the compressor for evaporating the coolant compressed by the compressor; and a condenser connected to the evaporator for condensing the coolant evaporated by the evaporator, the condenser comprising a plurality of heat exchange modules, wherein each of the heat exchange modules includes first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe.

[15] In the heat accumulator system noted above, each of the first and second module bodies includes a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[16] In the heat accumulator system noted above, the curved outer surface portion is provided with a corrugated surface.

[17] In the heat accumulator system noted above, the condenser includes a hot water pipe extending through at least one of the heat exchange modules.

Advantageous Effects

[18] With the present heat exchange module using a latent heat material, it is possible not only to enhance the transfer of heat or cold energy but also to increase the efficiency and convenience-in-use of the heat exchange module because the heat exchange module is attachable to the coolant pipe with ease. In addition, the heat exchange module can be used as a condenser or an evaporator, in which case it becomes possible to increase the energy use efficiency.

[19] The heat exchange module using a latent heat material in accordance with the present invention finds its application in a condenser or an evaporator for various kinds of air- conditioning systems.

Brief Description of the Drawings

[20] Fig. 1 shows a conventional storage container for storing a latent heat material.

[21] Fig. 2 is a configuration diagram illustrating a heat accumulator system in accordance with one preferred embodiment of the present invention, which incorporates a heat exchange module using a latent heat material. [22] Fig. 3 is an exploded perspective view illustrating a heat exchange module using a latent heat material in accordance with one preferred embodiment of the present invention. [23] Fig. 4 is a section view showing a right hollow module body of the heat exchange module illustrated in Fig. 3. [24] Fig. 5 is a perspective view illustrating the use of the present heat exchange module as a condenser. [25] Fig. 6 is a perspective view illustrating the use of the present heat exchange module as an evaporator.

Best Mode for Carrying Out the Invention [26] Preferred embodiments of a heat exchange module and a heat accumulator system in accordance with the present invention will now be described in detail with reference to the accompanying drawings. [27] Referring to Figs. 2 through 4, there are illustrated a heat accumulator system and a heat exchange module using a latent heat material employed in the heat accumulator system. [28] The heat accumulator system shown in Fig. 2 is a system in which a latent heat material absorbs or releases a specified amount of heat when it is phase-changed from solid to liquid or vice versa. [29] The heat accumulator system is designed to operate an air-conditioning device primarily in the midnight time so that the heat or cold energy generated during a condensing or evaporating process can be accumulated in a heat exchange module using a latent heat material. The heat or cold energy thus accumulated is used for a heating or cooling purpose in the daytime when the air-conditioning device remains inoperative. [30] Referring to Fig. 2, the heat accumulator system incorporating the heat exchange module using a latent heat material includes a compressor 13 for compressing coolant, an evaporator 11 connected to the compressor 13 for evaporating the coolant compressed by the compressor 13 and a condenser 15 connected to the evaporator 11 for condensing the coolant evaporated by the evaporator 11. [31] In the evaporator 11, liquid coolant of low temperature and low pressure introduced therein is changed to gas coolant of high temperature and high pressure by absorbing heat from the environment. [32] The coolant discharged from the evaporator 11 flows toward the condenser 15 in which the gas coolant of high temperature and high pressure flowing out of the evaporator 11 is converted or condensed to liquid coolant of medium temperature. [33] The liquid coolant discharged from the condenser 15 is compressed by the compressor 13 and then re-introduced into the evaporator 11, thereby completing a coolant circulation cycle. The respective constituents of the heat accumulator system are connected by a coolant pipe 17. The coolant flowing through the coolant pipe 17 makes heat exchange with the ambient air so that the temperature thereof can be reduced.

[34] A heat exchange module 20 using a latent heat material is attached to the coolant pipe 17. The heat exchange module 20 may be attached to the coolant pipe 17 in the position of the condenser 15 so that it can serve as a condenser.

[35] In this case, the heat exchange module 20 plays a part of a condenser that converts the coolant of high temperature and high pressure to the coolant of medium temperature and high pressure by accumulating the heat of the coolant flowing through the coolant pipe 17 by use of the latent heat material. A below-mentioned hot water pipe 51 may extend through the heat exchange module 20 to supply hot water to the outside.

[36] The heat exchange module 20 may be attached to the coolant pipe 17 in the position of the evaporator 11 so that it can serve as an evaporator. In this case, the heat exchange module 20 plays a part of an evaporator that absorbs the cold energy of the coolant flowing through the coolant pipe 17 by use of the latent heat material and releases the cold energy while an air-conditioning system remains inoperative.

[37] The heat exchange module 20 is made of a polymer material or a metallic material with increased heat conductivity to assure smooth transfer of heat. The heat exchange module 20 includes a left hollow module body 21 and a right hollow module body 23 between which different extensions of the coolant pipe 17 are arranged as can be seen in Fig. 3.

[38] As can be seen in Fig. 4, each of the left and right hollow module bodies 21 and 23 is provided with a storage space 25 that receives the latent heat material. The latent heat material is able to accumulate heat or cold energy in the heat accumulator system. The latent heat generated in a phase-changing process of the latent heat material is used for a cooling or heating purpose.

[39] In case the heat exchange module 20 serves as the condenser 15, the latent heat material filled in the storage space 25 is made of a phase change material that changes its phase at a temperature of 30 to 48 C.

[40] In contrast, if the heat exchange module 20 serves as the evaporator 11, the latent heat material is made of a phase change material that changes its phase at a temperature of -40 to 0 C. The latent heat material serves to raise or lower the environmental temperature by releasing or absorbing a specified amount of heat when it is phase-changed from solid to liquid or from liquid to solid.

[41] Each of the left and right module bodies 21 and 23 has a generally flat inner coupling surface portion 27 on which a pair of coolant pipe receiving grooves 29 is formed in a laterally outwardly recessed shape. When the left and right module bodies 21 and 23 are separably combined together, the inner coupling surface portions 27 thereof make contact with each other.

[42] The respective extensions of the coolant pipe 17 are received within the coolant pipe receiving grooves 29 of the left and right module bodies 21 and 23. Although two coolant pipe receiving grooves 29 are formed one above another in the embodiment shown in Fig. 3, the number of the coolant pipe receiving grooves 29 may be greater or lesser.

[43] Each of the left and right module bodies 21 and 23 has upper and lower curved outer surface portions 31 formed on an opposite side from the inner coupling surface portion 27. The curved outer surface portions 31 are formed to have a generally constant radius of curvature, i.e., a generally uniform radius R measured from each of the coolant pipe receiving grooves 29 as illustrated in Fig. 4. Just like the coolant pipe receiving grooves 29, the curved outer surface portions 31 are formed one above another on the lateral outer side of each of the left and right module bodies 21 and 23.

[44] The reason for forming the curved outer surface portions 31 with a generally uniform radius R is to ensure that the distance between the respective extensions of the coolant pipe 17 and the curved outer surface portions 31 becomes uniform, thereby allowing heat exchange to occur in a smooth manner.

[45] A corrugated surface 33 is formed on the curved outer surface portions 31 of the left and right module bodies 21 and 23. The corrugated surface 33 serves to prevent the left and right module bodies 21 and 23 from being broken when the latent heat material is expanded within the storage space 25 and also to increase the heat transfer area during heat exchange.

[46] The corrugated surface 33 extends from a point spaced apart a predetermined distance from the top end of the upper curved outer surface portions 31 to the bottom end of the lower curved outer surface portions 31. The reason for this is that the latent heat material is filled in the left and right module bodies 21 and 23 to occupy 90% of the total volume thereof and the air is filled to occupy the remaining 10% of the total volume. This allows the left and right module bodies 21 and 23 to withstand the volumetric change of the latent heat material during a phase changing process. For this reason, it is preferred that the corrugated surface 33 be formed to occupy about 90% of the total volume of each of the left and right module bodies 21 and 23.

[47] On the upper surface of each of the left and right module bodies 21 and 23, there is formed a mouth 35 through which the latent heat material is filled in the storage space 25. Once the latent heat material is filled in the storage space 25, the mouth 35 is closed by a sealing cap made of the same material as that of the left and right module bodies 21 and 23. [48] A plurality of bolt holes 37 is formed through the thickness of each of the left and right module bodies 21 and 23. Bolts are inserted into the bolt holes 37 and tightened by nuts to combine the left and right module bodies 21 and 23 together.

[49] Furthermore, a plurality of clamp receiving grooves 39 is formed in the upper and lower curved outer surface portions 31 of the left and right module bodies 21 and 23. Fitted to each of the clamp receiving grooves 39 is a clamp 40 for fixing the left and right module bodies 21 and 23 to a mounting frame 50 (see Figs. 5 and 6).

[50] Fig. 5 illustrates the use of the heat exchange module 20 as a condenser. As illustrated, the condenser includes a plurality of the heat exchange modules 20 arranged one above another in plural columns and rows. The heat exchange modules 20 are fixed to the mounting frame 50.

[51] The respective extensions of the coolant pipe 17 extend through the heat exchange modules 20 so that the coolant can flow through the respective heat exchange modules 20. The respective extensions of the coolant pipe 17 are serially connected to one another.

[52] The heat released from the coolant pipe 17 is absorbed by the latent heat material stored within the respective heat exchange modules 20. At this time, the latent heat material is phase-changed from solid to liquid to accumulate the heat released from the coolant pipe 17.

[53] A hot water pipe 51 extends through some of the heat exchange modules 20. The water flowing through the hot water pipe 51 is heated by the heat accumulated in the heat exchange modules 20. The hot water in the hot water pipe 51 is supplied to the outside and used in heating a room or as a tap water.

[54] Fig. 6 illustrates the use of the heat exchange module 20 as an evaporator. As illustrated, the evaporator includes a plurality of the heat exchange modules 20 arranged in parallel to one another. The heat exchange modules 20 are fixed to the mounting frame 50. The respective extensions of the coolant pipe 17 extend through the heat exchange modules 20.

[55] The mounting frame 50 illustrated in Fig. 6 is preferably used in a place where there exists a lot of restrictions in installing the mounting frame 50, e.g., in a refrigerator truck. The respective extensions of the coolant pipe 17 is serially connected to one another and arranged to extend through all of the heat exchange modules 20.

[56] Coolant of low temperature and low pressure flows through the coolant pipe 17 to change the temperature of the latent heat material stored in the heat exchange modules 20. In other words, the latent heat material stored in the heat exchange modules 20 is phase-changed from solid to liquid to thereby accumulate the cold energy.

[57] Description will now be made on the operation of the present heat exchange module using a latent heat material as configured above. [58] First, the latent heat material is supplied into the left and right module bodies 21 and

23 through the mouth 35 so that about 90% of the storage space 25 can be filled with the latent heat material.

[59] Once the latent heat material is filled in the left and right module bodies 21 and 23, a sealing cap is fusion-bonded to the mouth 35 to thereby hermetically seal the left and right module bodies 21 and 23. Then, the respective extensions of the coolant pipe 17 are received in the coolant pipe receiving grooves 29 formed on the inner coupling surface portion 27 of each of the left and right module bodies 21 and 23.

[60] After the respective extensions of the coolant pipe 17 are received in the coolant pipe receiving grooves 29, bolts are inserted into the bolt holes 37 of the left and right module bodies 21 and 23 and tightened by use of nuts to thereby combine the left and right module bodies 21 and 23 together. Then, the clamp 40 is fitted to the clamp receiving grooves 39 of the left and right module bodies 21 and 23 and fixedly secured to the mounting frame 50. At this time, a plurality of the left and right module bodies 21 and 23 may be arranged one above another and then fixed to the mounting frame 50 by a plurality of the clamps 40. Furthermore, the hot water pipe 51 may be arranged between the left and right module bodies 21 and 23.

[61] In this manner, a plurality of the left and right module bodies 21 and 23 is attached to the mounting frame 50. As the coolant is allowed to flow through the coolant pipe 17, active heat exchange occurs between the coolant pipe 17 and the left and right module bodies 21 and 23 that are kept in close contact with each other.

[62] Since the left and right module bodies 21 and 23 have the upper and lower curved outer surface portions 31 equidistantly spaced from the coolant pipe receiving grooves 39, the heat exchange occurs within the storage space 25 in a generally uniform pattern. At this time, the corrugated surfaces 33 formed in the left and right module bodies 21 and 23 allow the left and right module bodies 21 and 23 to be expanded or contracted in response to the phase change of the latent heat material.

[63] In the state that a plurality of the heat exchange modules 20 is attached to the mounting frame 50, the heat exchange modules 20 are able to serve as a condenser or an evaporator. First, the role of the heat exchange modules 20 as a condenser will be described with reference to Fig. 2. The coolant of high temperature and high pressure discharged from the evaporator 11 flows through the coolant pipe 17 surrounded by the heat exchange modules 20.

[64] The latent heat material stored within the heat exchange modules 20 is heated by the coolant of high temperature and high pressure flowing through the coolant pipe 17 and is phase-changed from solid to liquid to thereby accumulate the heat released from the coolant. The coolant flowing through the coolant pipe 17 is condensed into liquid by releasing heat to the latent heat material of relatively low temperature. [65] Thus, the heat exchange modules 20 serve as a condenser by which the coolant of high temperature and high pressure is changed to the coolant of low temperature and low pressure. The coolant passing through the heat exchange modules 20 is introduced into the compressor 13.

[66] If the heat is accumulated in the latent heat material of the heat exchange modules 20 through the above-noted process, the temperature of the water flowing through the hot water pipe 51 arranged in the heat exchange modules 20 is increased. The hot water in the hot water pipe 51 is supplied to the outside and is used as heating water or tap water.

[67] During the daytime when the heat accumulator system stays inoperative, the latent heat material stored in the heat exchange modules 20 is phase-changed from liquid to solid. In this process, the water flowing through the hot water pipe 51 is heated by the heat released from the latent heat material. This makes it possible to continuously supply the hot water to the outside.

[68] Next, the role of the heat exchange modules 20 as an evaporator will be described with reference to Fig. 2. The coolant of medium temperature and high pressure discharged from the compressor 13 is changed to coolant of low temperature and low pressure in the evaporator 11. Then, the coolant of low temperature and low pressure absorbs heat from the latent heat material of liquid phase while flowing through the coolant pipe 17 arranged in the heat exchange modules 20.

[69] Consequently, the coolant in the coolant pipe 17 is evaporated and the latent heat material of liquid phase is changed to a solid phase so that it can accumulate cold energy. The coolant leaving the coolant pipe 17 in the evaporator 11 is supplied to the compressor 13 via the condenser 15 and is circulated through the heat accumulator system.

[70] If the latent heat material stored in the heat exchange modules 20 sufficiently absorbs cold energy and the temperature of the latent heat material is decreased to below a phase change temperature, the heat accumulator system stops its operation. Even when the heat accumulator system remains inoperative, the latent heat material stored in the heat exchange modules 20 is phase-changed from solid to liquid and continues to release cold energy.

[71] In this way, the heat exchange modules 20 serve as an evaporator by supplying cold energy during the time when the heat accumulator system is kept inoperative. If the latent heat material stored in the heat exchange modules 20 is completely phase- changed from solid to liquid, the heat accumulator system is operated again to repeat the process set forth above.

[72] As is apparent from the foregoing, the heat exchange module using a latent heat material in accordance with the present invention is capable of serving as a condenser, an evaporator or both.

[73] The present application contains subject matter related to Korean Patent Application

No. 10-2007-0085055, filed in the Korean Intellectual Property Office on August 23, 2007, the entire contents of which is incorporated herein by reference.

[74] While the present invention has been described with respect to the specific embodiments, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims

[1] A heat exchange module comprising first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material makes heat exchange with the coolant pipe.

[2] The heat exchange module as recited in claim 1, wherein each of the first and second module bodies includes a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[3] The heat exchange module as recited in claim 2, wherein the curved outer surface portion is provided with a corrugated surface.

[4] A heat accumulator system including: a compressor for compressing coolant; an evaporator connected to the compressor for evaporating the coolant compressed by the compressor, the evaporator comprising a plurality of heat exchange modules, wherein each of the heat exchange modules includes first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe; and a condenser for condensing the coolant evaporated by the evaporator.

[5] The heat accumulator system as recited in claim 4, wherein each of the first and second module bodies includes a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[6] The heat accumulator system as recited in claim 5, wherein the curved outer surface portion is provided with a corrugated surface.

[7] A heat accumulator system comprising: a compressor for compressing coolant; an evaporator connected to the compressor for evaporating the coolant compressed by the compressor; and a condenser connected to the evaporator for condensing the coolant evaporated by the evaporator, the condenser comprising a plurality of heat exchange modules, wherein each of the heat exchange modules includes first and second hollow module bodies separably combined together, each of the first and second module bodies being filled with a latent heat material, and a coolant pipe arranged between the first and second module bodies so that the latent heat material can make heat exchange with the coolant pipe.

[8] The heat accumulator system as recited in claim 7, wherein each of the first and second module bodies includes a generally flat inner coupling surface portion having a coolant pipe receiving groove for receiving the coolant pipe and a curved outer surface portion having a generally uniform radius as measured from the coolant pipe receiving groove.

[9] The heat accumulator system as recited in claim 8, wherein the curved outer surface portion is provided with a corrugated surface.

[10] The heat accumulator system as recited in claim 7, wherein the condenser includes a hot water pipe extending through at least one of the heat exchange modules.