TWI731501B - Heat exchange device - Google Patents

Abstract

A heat exchange device comprises a plurality of heat conduction unit, and a housing unit which is adapted to contain said heat conduction unit. Each heat conduction unit includes a rough thermal plate, and a plurality of porous thermal fin which is mounted on said thermal plates. Said thermal fins are porous, which can reduce the pressure loss of the passing steam to avoid steam blocking. The rough surface of said thermal plates can significantly increase the heat exchange area of steam, and increase the contact area with the heat storage fluid without too much pressure loss.

Description

Heat exchange device

The invention relates to a heat exchange device, in particular to a gas-liquid heat exchange device.

Heat exchangers have been used in refrigeration and air conditioning, heat pumps, and industrial processes for a long time. Traditional heat exchangers include shell and tube, plate and fin tube types. The development of this type of heat exchanger has matured, but it is still subject to operating pressure, Temperature range, efficiency, volume, pressure loss and other conditions limit its application environment. On the other hand, the current power generation in hot spring fields is dominated by deep geothermal energy, and the natural discharge steam from hot spring wells is still close to 130°C, which has great potential for power generation and reuse. However, as mentioned above, traditional heat exchangers cannot meet the requirements. Low-pressure loss, high-temperature resistance, high-pressure resistance, corrosion resistance and other requirements required for thermal energy conversion applications such as low-temperature exhaust gas or geothermal steam in renewable energy. High-pressure loss will cause steam to be easily blocked when passing through the heat exchanger and cause danger, and contact with steam There is still room for improvement of the heat exchange area.

Therefore, the object of the present invention is to provide a heat exchange device with a high air side heat exchange surface area and a reduced pressure.

Therefore, the heat exchange device of the present invention includes a plurality of heat-conducting units and a housing unit for accommodating the heat-conducting units. Each heat-conducting unit includes a heat-medium plate that surrounds a plurality of liquid flow channels and has a rough surface, and a plurality of porous heat-conducting fins are arranged on the heat-medium plate at intervals. The housing unit includes a shell tube that defines a high temperature air inlet, a low temperature air outlet opposite to the high temperature air inlet, a low temperature heat medium inlet, and a high temperature opposite to the low temperature heat medium inlet Heat medium outlet, the opposite ends of each liquid flow channel are respectively connected with the low temperature heat medium inlet and the high temperature heat medium outlet, and the heat of every two adjacent heat-conducting fins and the heat-medium plate and the adjacent heat-conducting unit The media plates cooperate to define a gas flow channel with two ends respectively communicating with the high temperature air inlet and the low temperature air outlet.

The effect of the present invention is that the heat conduction fins of the heat conduction units are porous, which can reduce the pressure loss of the steam passing through, so as to avoid the situation of steam clogging. In addition, the heat medium plate has a roughened outer surface. The heat exchange area of the steam is greatly increased, and the effect of gas turbulence is generated, thereby improving the heat transfer performance. In addition, the roughened inner surface of the heat medium plate can increase the contact area with the heat storage fluid without increasing too much pressure loss.

Referring to FIGS. 1, 2, and 3, an embodiment of the heat exchange device of the present invention includes a housing unit 1 and a plurality of heat conducting units 2 fixed side by side in the housing unit 1. The housing unit 1 includes a hollow shell tube 11 that defines a high temperature air inlet 111 located at both ends of the shell tube 11 in the axial direction, and a low temperature air outlet 112 opposite to the high temperature air inlet 111, In addition, a low temperature heat medium inlet 113 located on opposite sides of the shell tube 11 in a radial direction and a high temperature heat medium outlet 114 opposite to the low temperature heat medium inlet 113 are defined. The shell tube 11 defines an inlet space 115 communicating with the low temperature heat medium inlet 113 and an outlet space 116 separated from the liquid inlet space 115 and communicating with the high temperature heat medium outlet 114. In this embodiment, the shell tube 11 is made of multiple layers of heat storage materials, such as multiple layers of glass fiber or multiple layers of alumina, which have better heat storage performance to absorb and store the heat energy that may escape. It should be particularly noted that, although the shell tube 11 is displayed in the form of a round tube in the drawing of this case, it can actually be a square tube or a tube body of other shapes as required.

Referring to FIGS. 2, 3, and 4, each heat conducting unit 2 includes a heat medium plate 21 that surrounds a plurality of liquid flow channels 211 and has a roughened surface, and the plurality of heat medium plates 21 are spaced apart from each other along the axial direction of the shell tube 11 The heat-conducting fin 22 is erected on one side of the heat medium plate 21. The opposite ends of the heat medium plate 21 in the axial direction of the shell tube 11 are gradually folded outward to form the tips 212, and the tips 212 have the function of diversion, so that the gas enters more smoothly. In this embodiment, the heat medium plate 21 and the thermally conductive fins 22 are integrally formed, and are made of 420 stainless steel powder with selective laser melting and milling combined processing manufacturing technology, which is resistant to high temperature and high pressure. Characteristics, and the roughness (Ra) of the outer surface and the inner surface is less than 50μm. The liquid flow passages 211 extend along the radial direction of the shell tube 11, and the two ends of each liquid flow passage 211 are respectively connected to the liquid inlet space 115 and the liquid outlet space 116 so as to be connected to the low temperature heat medium respectively The inlet 113 and the high-temperature heat medium outlet 114 are connected. In this embodiment, the cross section of each liquid flow channel 211 is a non-circular cross section, which can increase the heat exchange surface area. Each heat-conducting fin 22 extends along the axial direction of the shell tube 11, and can be wavy, zigzag, or columnar as required. The heat-conducting fin 22 is a porous material as shown in FIG. 5, with a porosity≦ 50%, porosity>1mm, and the porosity is preferably 100~500μm. The heat medium plate 21, the heat conducting fins 22, and the heat medium plate 21 of another adjacent heat conducting unit 2 cooperate with each other to define a plurality of gas flow channels 23 extending in the axial direction of the shell tube 11 . Furthermore, the heat conducting units 2 can also be applied to shells of other shapes or forms, to exert their gas-liquid fluid cross-arrangement, and increase the contact area through surface roughness and porosity to improve heat transfer performance. Features, even a single heat conduction unit 2 can be used alone, not limited to this.

When this embodiment is in use, the low-temperature heat storage fluid is sent from the low-temperature heat medium inlet 113 into the liquid flow passages 211 through the liquid inlet space 115, and steam or exhaust gas (hereinafter collectively referred to as gas) The high-temperature air inlet 111 enters the gas flow passages 23, and when the gas flows in each gas flow passage 23, it flows between the porous thermally conductive fins 22 and the heat medium plate 21 whose outer surface is roughened , Can greatly increase the heat exchange surface area, and transfer heat energy to the heat storage fluid in the liquid channels 211, and finally the gas with a lower temperature is sent out from the low-temperature outlet 112, and the heat storage fluid with a higher temperature is sent by the high-temperature heat medium Exit 114 output. In addition to increasing the contact area, the porous thermally conductive fins 22 can also generate irregular turbulent flow fields and reduce pressure loss during gas flow, improve heat transfer performance and eliminate the sensitivity to steam or exhaust gas blockage, and reduce heat. The loss can reach 3.55% or less.

The preferred operating environment of this embodiment is as follows: the operating temperature is between 300°C and 900°C, the operating pressure is between 10 and 140 Pa, the heat transfer coefficient of the thermally conductive fins 22 can reach 530.7W/m ² K, and the surface The heat transfer efficiency reaches 0.993, the pressure drop on the air side is about 101.55kPa, and the pressure drop on the liquid side is about 102.5Pa.

This embodiment can integrate the application of hydrogen fuel cell for thermoelectric conversion. The heat storage fluid output from the high temperature heat medium outlet 114 can be used to preheat the anode reaction gas of the hydrogen fuel cell to increase the electrochemical reaction speed and protons in the electrolyte membrane. At the same time, the reaction gas at the cathode end is preheated to improve the gas diffusion capacity in the catalyst layer and the gas diffusion layer (GDL) to maintain the power conversion efficiency of the hydrogen fuel cell. On the other hand, it can be Another heat exchange device is used to quickly absorb and discharge the water vapor generated by the cathode of the hydrogen fuel cell. The heat energy obtained from the water vapor can be used to warm the water body and prevent the water vapor from interfering with the hydrogen fuel cell. The hydrogen fuel cell can be used for waste heat management and use, so that the battery can be maintained at an operating temperature below 85°C, and the chemical energy conversion efficiency of the hydrogen fuel cell can be maintained at 40% to 60% to maintain efficient operation.

Another application of this embodiment is the integration of the thermally regenerated ammonia fuel cell (Thermally Regenerative Ammonia-based Battery, TRAB). The thermal energy obtained by the heat exchange device is used to introduce the ammonia evaporation and condensation in the original anode electrolyte of the thermally regenerated ammonia fuel cell into the original The cathode, the anode electrode that promotes the regeneration of chemical energy and is also consumed due to the reaction, allows the thermally regenerated ammonia fuel cell to continue to react, achieving the effect of converting waste heat into chemical energy and charging.

In summary, the heat exchange device of the present invention can reduce the pressure loss on the air side through the porous thermally conductive fins 22 and eliminate the susceptibility to clogging on the vapor side. The vapor or exhaust gas is in the closely arranged thermally conductive fins. The turbulent flow effect is generated between the 22 and the outer surface of the heat medium plate 21, and the porous and roughened process treatment can greatly increase the heat exchange area and improve the overall heat transfer performance, so it can indeed achieve the purpose of the invention.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

1········ Housing unit 11······Shell and tube 111····· High temperature inlet 112····· Low temperature inlet 113····· Low temperature heat medium entrance 114····· High temperature heat medium outlet 115····· Into the liquid space 116····· Outlet Space 2········ Heat conduction unit 21······Heat Medium Plate 211····· Liquid flow path 212·····tip 22······ Thermal Conductive Fin 23······Gas flow path

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: Figure 1 is a perspective view illustrating an embodiment of the heat exchange device of the present invention; Figure 2 is a top cross-sectional view illustrating the top cross-sectional aspect of this embodiment; Figure 3 is a front cross-sectional view illustrating the front cross-sectional aspect of this embodiment; Fig. 4 is an incomplete three-dimensional view illustrating a plurality of heat conducting units of this embodiment; and Fig. 5 is an enlarged partial cross-sectional view illustrating that the plurality of heat conduction fins of one of the heat conduction units are porous.

2········ Heat conduction unit 21······Heat Medium Plate 211····· Liquid flow path 212·····tip 22······ Thermal Conductive Fin 23······Gas flow path

Claims (9)

A heat exchange device includes: a plurality of heat conduction units, each heat conduction unit includes a heat medium plate with a rough surface surrounding a plurality of liquid flow channels, and a plurality of heat medium plates are arranged at intervals and are porous High-quality thermally conductive fins, each thermally conductive fin having a plurality of through holes with pores ranging from 100 μm to 500 μm; and a housing unit for accommodating the heat-conducting units. The housing unit includes a shell tube that defines a A high temperature air inlet, a low temperature air outlet opposite to the high temperature air inlet, a low temperature heat medium inlet, and a high temperature heat medium outlet opposite to the low temperature heat medium inlet. The opposite ends of each liquid flow channel are respectively Connecting the low-temperature heat medium inlet and the high-temperature heat medium outlet, every two adjacent heat-conducting fins cooperate with the heat-medium plate and the heat-medium plate of the adjacent heat-conducting unit to define a two ends respectively connected to the heat medium plate The high-temperature gas inlet and the gas flow channel of the low-temperature gas outlet. The heat exchange device according to claim 1, wherein the liquid flow channels of each heat conduction unit have a non-circular cross section. The heat exchange device according to claim 1, wherein the outer shape of the heat conduction fins of each heat conduction unit is one of wavy, zigzag, and columnar shapes. The heat exchange device according to claim 1, wherein the heat medium plate of each heat conduction unit is integrally formed with the heat conduction fins. The heat exchange device according to claim 1, wherein each heat conduction unit is made of stainless steel. The heat exchange device according to claim 2, wherein each liquid flow channel extends in the radial direction of the shell tube, and each gas flow channel extends in the axial direction of the shell tube stretch. The heat exchange device according to claim 2, wherein the shell tube defines a liquid inlet space communicating with one end of the liquid flow channels and the low-temperature heat medium inlet, and a liquid inlet space is separated from and communicated with the liquid inlet space The other end of the liquid flow channels and the liquid outlet space of the high temperature heat medium outlet. The heat exchange device according to claim 2, wherein the opposite ends of the heat medium plate of each heat conduction unit in the axial direction of the shell tube gradually collapse outward to form a tip. The heat exchange device according to claim 2, wherein the shell tube of the shell unit is made of multilayer glass fiber or alumina.

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