KR102572792B1 - Rapid cooling heat exchaning method using cavitation generators and felt-thermal thermocouples - Google Patents

Abstract

The present invention includes a Peltier thermoelectric element (hereinafter referred to as Peltier) 130, an ultrasonic generator 110, a bubble supplier 120, and a bubble supply pipe 180 (hereinafter referred to as a cavitation generator), and is generated by the cavitation generators 110, 120, and 180. The present invention relates to a heat exchange device in which cavitation is frozen when it passes through the peltier 130 and rapidly cools a high-temperature fluid by thawing of cavitation and cavitation extinction.
Cavitation generators 110, 120 and 180 according to the present invention as a means for achieving this; peltier 130; solid flow tube 170; cooling fins 150 surrounding the passage; A heat storage tank or water tank (hereinafter referred to as heat storage tank) 100 containing water or antifreeze (hereinafter referred to as cooling water) as cooling water; Blowing fan 160; temperature sensor 190; A driving circuit for applying driving power to the cavitation generators 110 , 120 , and 180 , the peltier 130 , and the blowing fan 160 and a control device (not shown) are provided.
According to the present invention, the cavitation generated by the cavitation generators 110, 120, and 180 is finely frozen by the cooling function of the peltier 130, and the cavitation thawed in the heat storage tank 100 warmed by the hot fluid expands while moving upward, and the cavitation By the extinction process, the cooling water inside the heat storage tank 100 is forcibly circulated to quickly cool the inside. In addition, water vapor generated inside the heat storage tank 100 is quickly condensed by the blowing fan 160 and the upper part of the heat storage tank 100 is cooled.
According to the present invention, a rapid cooling device equipped with a temperature sensor 190 and capable of controlling a high-temperature fluid to an appropriate temperature can be manufactured in a compact size, and a cooling heat exchanger can be economically configured.

Description

Rapid cooling heat exchaning method using cavitation generators and felt-thermal thermocouples}

The present invention relates to a heat exchange device for rapidly cooling by generating ice with a Peltier thermoelectric element (hereinafter referred to as Peltier) 130, an ultrasonic generator or an air bubble supplier and a bubble supply pipe (hereinafter referred to as a cavitation generator), and more particularly, generates cavitation. The devices 110, 120, and 180 and the peltier 130 are provided, and the cavitation generated by the cavitation generators 110, 120, and 180 is frozen near the peltier 130, and heat for rapidly cooling the high-temperature passage by the cavitation thawing and cavitation extinction process. It relates to an exchange device and a heat exchange method.

Thermoelectric elements include a device using a temperature change in electrical resistance (thermistor) using a thermoelectric effect, a device using a phenomenon (Seebeck effect) in which electromotive force is generated by a temperature difference, and a heat absorption (or generation) by current There is a device (Peltier device) that uses the phenomenon (Peltier effect) that generates.

According to the heat transfer method of the heat exchanger, there are a surface heat exchanger, a regenerative heat exchanger, a liquid connection indirect heat exchanger, and a direct contact heat exchanger. The heat exchanger similar to that of the present invention is a heat storage type, which brings a solid heat storage agent (a medium for storing heat) into contact with a high-temperature fluid to absorb heat from the high-temperature fluid, and then contacts the low-temperature fluid to transfer heat to the low-temperature fluid. As the heat exchanger, there are a rotary regenerative heat exchanger, a valve type annular regenerative heat exchanger, and the like. When a conventional regenerative heat exchanger is used for a high-temperature fluid, it is difficult to complicate and compact the system.

Republic of Korea Patent Publication No. 10-2016-0078764 provides a cooling device using ultrasonic waves of a piezoelectric element that cools using ultrasonic waves generated from a piezoelectric element. A cooling device using ultrasonic waves according to an embodiment of the present invention is installed inside a housing containing a compressible working fluid, the housing divides a first space and a second space on both sides, and the first space and the second space are installed. A stack having a channel through which the working fluid vibrates and moves between two spaces, a pair of heat exchangers provided on both sides of the stack inside the housing, and the housing facing any one of the pair of heat exchangers It includes a piezoelectric element provided inside. Korean Patent Publication No. 2000-0059898 An automatic ice maker using sonic wave refrigeration and a refrigerator employing the automatic ice maker are disclosed. The automatic ice maker is a U-shaped resonator that stores inert gas inside, and a speaker that changes the temperature distribution inside the U-shaped resonator by applying negative pressure to the U-shaped resonator to compress and expand the molecules of the inert gas stored in the U-shaped resonator. , a heat exchanger that transfers the internal temperature of the U-shaped resonator to an ice container and forms a passage therein, and an electronic control unit that operates a speaker. As such, the wave cooling method converts wave energy into kinetic energy to obtain a cooling effect. For another example, the wave cooling device generates sound waves with a speaker provided on one side of a housing and transfers the wave energy of the sound waves to an internal passage of a stack installed in the housing, wherein a working fluid is provided on both sides of the stack for cold heat exchange. It cools while vibrating and moving between the heat exchanger and the hot heat exchanger.

An object of the present invention is to provide a heat exchange device that rapidly cools an input high-temperature fluid using a cavitation phenomenon and a peltier 130 and discharges the fluid by controlling the temperature. In addition, it is to provide an economical heat exchanger that allows the rapid cooling heat exchanger to be compact and inexpensive.

Cavitation generators 110, 120 and 180 according to the present invention as a means for achieving this; peltier 130; solid flow tube; a cooling fin structure surrounding the passage; A heat storage tank 100 containing cooling water; Blowing fan 160; temperature Senser; A driving circuit and a control device for applying driving power to the cavitation generating devices 110 , 120 , and 180 , the peltier 130 , and the blowing fan 160 are provided.

According to the present invention, the cavitation generated by the cavitation generators 110, 120, and 180 is finely frozen by the cooling function of the peltier 130. The cavitation melted inside the heat storage tank 100 warmed by the hot flow path expands while moving upward, and the cooling water inside the heat storage tank 100 is forcibly circulated through the cavitation extinction process to rapidly cool the inside. In addition, cold wind is supplied to the inside of the heat storage tank 100 by the blower fan 160 at the top, the water vapor generated inside the heat storage tank 100 is quickly condensed, and the temperature of the upper part of the heat storage tank 100 is cooled. In addition, the cooled fluid is discharged at an appropriate temperature by controlling the cavitation generators 110, 120, and 180, the peltier 130, and the blowing fan 160 with reference to the temperature sensor.

According to an embodiment of the present invention, cavitation is generated by the cavitation generators 110, 120, and 180, cavitation passing through the cooling portion of the peltier 130 is frozen while moving through the Venturi tube, and as the frozen cavitation rises, melting and cavitation occur. Through the dissipation process, forced circulation of the cooling water is made and rapid cooling is possible.

In addition, cold wind is supplied to the blower fan 160 at the top of the regenerator to condense water vapor to recover heat, and the condensed liquid is re-supplyed to the surface of the cooling water to increase the cooling effect. Simple cavitation generators 110, 120, and 180 130) has the effect of rapidly cooling the high-temperature fluid in the smallest size, and economical configuration is possible.

- Figure 1 is a perspective view of a rapid cooling heat exchanger according to an embodiment of the present invention
- Figure 2 is a temperature distribution diagram inside the rapid cooling heat exchanger according to an embodiment of the present invention
- Figure 3 is a perspective view of a solid fluid pipe composed of a manifold
- Figure 4a is a cooling plate for increasing the cooling efficiency of the solid fluid pipe
- Figure 4b is a cooling fin structure surrounding the outside of the cooling plate
- Figure 5 is a graph showing the frequency of the ultrasonic transducer and the size of the cavitation that occurs
- Figure 6 shows the structure of the bubble supply pipe including the micro nozzle and the shape installed at the bottom of the venturi pipe
- Figure 7 is a phase transition graph for cooling water (water)
- Figure 8 shows the operation of cavitation according to ultrasonic sound pressure
- Figure 9 shows the phenomenon that occurs when cavitation disappears in a fluid
- Figure 10 is a diagram representing the rapid cooling step according to the present embodiment

An embodiment of the present invention is disclosed in FIG. First, with reference to the drawings, a rapid cooling heat exchanger using cavitation and the Peltier 130 will be described.

The cooling heat exchanger according to the present invention includes a solid flow tube; heat storage tank 100; cooling water; cooling fins; Peltier 130 and the heater sink module; ultrasonic generator; bubble supplier; air bubble supply pipe; Blowing fan 160; temperature Senser; It consists of an electronic control unit.

The solid flow pipe of FIG. 1 is configured to support high temperature and high pressure, and may be configured as a zigzag horizontal or vertical pipe. In addition, the internal configuration of the horizontal or vertical pipe may be provided in the form of a manifold as shown in FIG. The inlet of the solid flow pipe into which the high-temperature fluid is injected in FIG. 3 and the water tank are separated by an insulating material.

As shown in FIG. 1, the heat storage tank 100 includes a solid flow pipe therein; Cooling fins that expand the heat exchange area by adhering to the solid flow tube; ultrasonic generator; cooling water; air bubble supply pipe; A venturi tube is provided. A coolant inlet cap outside the heat storage tank 100; Blowing fan 160; bubble supplier 120; temperature Senser; Peltier 130 and the heat sink module; A control unit for power driving is provided. In addition, the heat storage tank 100 is sealed except for the solid flow pipe so that high-temperature water vapor is not exposed to the outside.

2 shows the temperature distribution in the heat storage tank 100. The temperature distribution is lower in the lower layer than the upper layer, and the density is higher in the lower layer than in the upper layer. Since the frozen cavitation is thawed as it rises, and the size of the cavitation quickly reaches a critical size in the middle layer and disappears, the temperature distribution according to the height of the heat storage tank 100 has a small temperature change in the upper and lower layers, and a lot of heat exchange in the middle layer It is done.

The cooling fin of FIG. 1 can be configured independently as shown in FIG. 4A or 4B, but in the embodiment, the concavo-convex structure of FIG. 4B is provided in the upper and lower parts of the cooling plate of FIG. It is provided to increase the contact area with the maximum.

The ultrasonic generator, bubble supplier, and bubble supply pipe of FIG. 1 are provided as a cavitation generator for generating cavitation.

5 shows the particle size of cavitation versus the frequency of the ultrasonic generator. Cavitation has a large size of cavitation particles at low frequencies in the ultrasonic frequency band, and decreases at higher frequencies. The frequency selection of the ultrasonic generator is determined in consideration of the size of the peltier 130 and crystal nuclei for freezing. The smaller the cavitation particle size, the larger the specific surface area, and crystal nuclei are easily generated in the cooling part of the peltier 130. However, if the size of cavitation is large, it is difficult to generate crystal nuclei, but the buoyancy is large and it can be effective for cooling. Therefore, considering the frequency of the ultrasonic generator in FIG. 5 at the same time as the specific surface area, crystal nucleus, and buoyancy, an ultrasonic vibration frequency of 50 KHz to 150 KHz is appropriate.

6 shows the progress of cavitation generated by the ultrasonic generator and the sound pressure of ultrasonic waves. On the surface of the ultrasonic generator, the negative pressure appears alternately with high pressure and low pressure, and at the low pressure position of the negative pressure, it is lower than the saturated vapor pressure of the liquid, and the liquid evaporates and creates cavitation. As the sound wave progresses, cavitation is compressed and expanded. When the cavitation particle size reaches a critical size, it is compressed and exploded and is extinguished. The cavitational explosion pushes the coolant into the upper layer where it is less dense. In addition, low pressure is formed at the point of explosion, which effectively provides a cooling function by attracting the cooling water in the lower layer where the temperature is low.

The method of extinguishing cavitation consists of two methods shown in FIG. The isotropic extinguishing method pushes the antifreeze in an isotropic form while extinguishing by receiving the same compression in all directions, and the anisotropic extinguishing method forms a microjet and strongly pushes the coolant to the upper layer with jet pressure. The bubble supplier may be composed of an air pump for exhausting external air to a bubble supply pipe at a constant pressure or an air pump for cavitation mixed with cooling water. The bubbles generated in the bubble supplier of FIG. 1 are exhausted adjacent to the peltier 130 through the bubble supply pipe micro-nozzle disposed below the Venturi tube as shown in FIG. 6 .

As shown in FIG. 6, the bubble supply pipe may be provided with micro nozzles such that the bubble has a radius of 2 to 4 μm, similarly to the ultrasonic generator. Bubbles provided from the bubble supply pipe operate in the same way as the above-described cation by the sound pressure of the ultrasonic generator. If the nozzle of the bubble supply pipe is enlarged to provide a lot of air, the cavitation generated by the ultrasonic generator rises rapidly like the mist of the ultrasonic humidifier and disappears in an isotropic or anisotropic form inside the cooling water or on the surface layer, thereby increasing the cooling efficiency.

In the embodiment of the present invention, the ultrasonic generator, the bubble supplier, and the bubble supply pipe are provided at the same time, but the ultrasonic generator, the bubble supplier, and the bubble supply pipe may be selectively provided. At this time, the bubble properties of each device are different. The ultrasonic generator provides negative pressure alternately with high pressure and low pressure so that cavitation repeats compression and expansion, and the bubble supplier has the difference that it forms simple micro bubbles, but the function of the cooling heat exchanger is provided the same. As shown in FIGS. 1 and 5, the cavitation generators 110, 120, and 180 are located in the lower part of the Venturi tube, and the peltier 130 and the cavitation generators 110, 120, and 180 are vertically adjacent to each other so that the generation and direction of cavitation is directed toward the upper layer. . The flow rate of cavitation increases through the Venturi tube, and the pressure inside the Venturi tube decreases, making it easy to generate ice.

Formation of ice formation will be described through a phase transition graph of water as cooling water in FIG. 7 . The same applies to using antifreeze as a coolant. In FIG. 7, cavitation occurs by the cavitation generators 110, 120, and 180, and low pressure is formed through the Venturi tube, so that the pressure is lowered from point A (liquid) to point B (gas), adjacent to the cooling part of the peltier 130. A phase transition occurs from point B (gas) to point C (freezing), and fine crystal nuclei are created, and the crystal nuclei grow into ice.

As shown in FIG. 1, the cooling part of the Peltier 130 is in contact with the heat storage tank 100, and the heating part is disposed outside. In order to maintain the cooling performance of the peltier 130, the heating unit is bonded to the heat sink module to increase the cooling efficiency of the peltier 130.

The temperature sensor of FIG. 1 is provided to measure the temperature of the lower layer of the heat storage tank 100, and the control unit controls driving power to the Peltier 130, the cavitation generators 110, 120, and 180, and the blowing fan 160 by the temperature sensor. The control unit applies a control signal to cool the Peltier 130 by applying a maximum current to the Peltier 130 when the temperature of the lower layer is higher than the set value using the temperature distribution diagram of FIG. 2 and to maximize the occurrence of cavitation. If the temperature is lower than the set value, the power applied to the peltier 130 is cut off, and the occurrence of cavitation is not blocked for forced circulation.

The blowing fan 160 of FIG. 1 condenses hot water vapor evaporating to the upper portion of the heat storage tank 100 and is provided so that the condensed cooling water can be supplied to the heat storage tank 100 again.
Figure 10 shows a processor in which the rapid cooling method of the present invention is configured. initially applying power to the cavitation generators 110, 120, and 180 to perform rapid cooling (P10); A step of forming a low pressure in the vicinity of the Venturi tube (P20); Driving the peltier 130 (P30); cooling the cooling water near the venturi tube (P40); Reaching the freezing point of the cooling water near the Venturi tube (P50); Formation of cavitation crystal nuclei in the vicinity of the Venturi tube (P60); growing crystal nuclei by freezing (P70); Primary cooling by heat exchange of frozen cavitation (P80); Pushing the coolant to the upper part of the lower density while the cavitation disappears (P90); Forcibly circulating cooling water to a place where cavitation is eliminated (P100); Condensing the water vapor by driving the blowing fan 160 (P110) is sequentially performed to forcibly circulate the cooling water inside the heat storage tank 100 to achieve rapid cooling.
More specifically, the present invention is a solid flow pipe for introducing a high-temperature fluid and discharging it as a cooled fluid, a cooling fin adhering to the solid flow pipe to widen a heat exchange area; A rapid cooling heat exchange method using a cavitation generator and a heat storage tank including a venturi tube and containing cooling water,
Generating cooling water by cavitation by the cavitation generator; passing the cavitation through a venturi tube; cooling the cavitation passing through the venturi tube by driving the peltier 130 (P30); Reaching the freezing point of the cooling water near the Venturi tube (P50); forming cavitation crystal nuclei in the vicinity of the venturi tube (P60); growing the crystal nuclei by freezing (P70); Primary cooling by heat exchange of frozen cavitation (P80); Pushing the coolant to the upper part of the lower density while the cavitation disappears (P90); Forcibly circulating cooling water to a place where cavitation is eliminated (P100); It is characterized in that rapid cooling is performed by forcibly circulating cooling water in the heat storage tank 100 by sequentially performing the step of condensing water vapor by driving the blowing fan 160 (P110).

In the step (P10) of applying power to the cavitation generators 110, 120, and 180 of the present invention, the ultrasonic generator applies ultrasonic vibration having an oscillation frequency of 50 to 150 kHz or operates a bubble supplier. Ultrasonic vibration causes a cavitation phenomenon in the cooling water shown in FIG. 7 .

Cavitation is a phenomenon in which microbubbles are created and destroyed by pressure changes of ultrasonic vibrations when ultrasonic vibrations are propagated in a liquid, and it is accompanied by very high pressure and high temperature. This pressure and high temperature occurs for a short time, on the order of hundreds of seconds to thousands of seconds.

In the step (P20) of forming a low pressure in the vicinity of the venturi tube, when the cavitation generated by the ultrasonic generator or the bubble generator passes through the tube in which the passage is narrowed, the speed is increased and the internal pressure is lowered.

In step 30 of driving the thermoelectric element of the peltier 130, power is applied to the peltier 130 based on the signal of the temperature sensor 1 and the cooling fan of the heat sink module mounted on the heating unit is driven. In the step of cooling the cooling water near the Venturi tube (P40), the cooling water in the portion of the Venturi tube adjacent to the cooling part of the Peltier 130 cools faster than the surroundings.

Referring to the phase transition graph at the stage where the cooling water reaches a certain point near the Venturi tube (P50), when the pressure in the Venturi tube decreases, the freezing point temperature of the cooling water rises from D->E, and the boiling point temperature goes from F->G It descends and reaches a certain point faster than its surroundings.

In the step of forming cavitation crystal nuclei near the Venturi tube (P60), crystal nuclei having a structure that easily grows into freezing or ice are formed. Due to the nature of crystal nuclei being sprayed at the same rate as the rate at which crystal nuclei are aggregated, aggregates cannot be formed. , a large number of crystal nuclei are produced. In addition, the pressure generated by the cavitation phenomenon when the bubble disappears and the discharge within the bubble trigger the formation of crystal nuclei.

In the step of growing crystal nuclei into freezing (P70), crystal nuclei (micro ice crystals) having a particle diameter of 0.01 to 0.001 mm centered on the crystal nucleus are rapidly grown by the cooling drive of the peltier 130, resulting in freezing. In the step of primary cooling by heat exchange of the frozen cavitation (P80), the frozen cavitation rising through the Venturi tube meets the cooled water warmed in the heat storage tank 100 and exchanges heat to provide a primary cooling function. In step P90 of pushing the cooling water to the upper part with low density as the cavitation disappears, when the cavitation is compressed and exploded, the high temperature and high pressure push the surrounding cooling water out. In the step of forcibly circulating the coolant to the place where the cavitation is eliminated (P100), low pressure is formed at the place where the explosion occurred, and the surrounding coolant is momentarily introduced to the forced circulation.

In the step of condensing the water vapor by driving the blowing fan 160 (P110), outside cold air is supplied into the heat storage tank 100 to condense the water vapor, and cooling water is re-supplied into the heat storage tank 100.

As described above, even if the high-temperature fluid is input to the heat storage tank 100 according to the embodiment of the present invention, the Peltier 130, the Venturi tube, the cavitation generators 110, 120, and 180, and the blowing fan 160 are provided, so that the inside of the heat storage tank 100 A rapid cooling heat exchanger is provided by primary cooling heat exchange using ice and secondary cooling heat exchange forcibly circulated by cavitation explosion.

Claims (11)

delete delete delete delete delete delete delete delete A solid flow pipe for introducing a high-temperature fluid and discharging it as a cooled fluid, and a cooling fin adhering to the solid flow pipe to increase a heat exchange area; A rapid cooling heat exchange method using a cavitation generator and a heat storage tank including a venturi tube and containing cooling water,
Generating cooling water by cavitation by the cavitation generator; passing the cavitation through a venturi tube; cooling the cavitation passing through the venturi tube by driving the peltier 130 (P30); Reaching the freezing point of the cooling water near the Venturi tube (P50); forming cavitation crystal nuclei in the vicinity of the venturi tube (P60); growing the crystal nuclei by freezing (P70); Primary cooling by heat exchange of frozen cavitation (P80); Pushing the coolant to the upper part of the lower density while the cavitation disappears (P90); Forcibly circulating cooling water to a place where cavitation is eliminated (P100); Condensing water vapor by driving the blowing fan 160 (P110); rapid cooling using a cavitation generator and a Peltier thermoelectric element characterized in that rapid cooling is performed by forcibly circulating cooling water in the heat storage tank 100 in turn heat exchange method
According to claim 9,
Rapid cooling heat exchange method using a cavitation generator and a Peltier thermoelectric element, characterized in that crystal nuclei are generated in the vicinity of the Venturi tube, the crystal nuclei are grown to form ice, and used for cooling.
According to claim 9,
Rapid cooling heat exchange method using a cavitation generator and a Peltier thermoelectric element, characterized in that as the cavitation disappears, the cooling water is pushed to a lower density upper part and the cooling water is forcibly circulated to the place where the cavitation is eliminated.

Images