Printed circuit board heat exchanger core employing hybrid fins

Abstract

This invention discloses a printed circuit board heat exchanger core employing hybrid fins. This core utilizes a hybrid fin design combining corrugated and spindle-shaped fins, solving the problems of insufficient compactness and drag reduction performance in existing printed circuit board heat exchanger cores. The core is composed of alternating stacked cold-side and hot-side heat exchange plates. The gaps between the heat exchange plates form cold-side and hot-side fluid channels, which are distributed alternately, allowing high and low temperature fluids to flow and exchange heat. Multiple sets of corrugated and spindle-shaped fins are arranged on the heat exchange plates along the fluid flow direction, and all fins are discontinuous. The use of hybrid fins effectively increases the heat exchange area, improving the compactness and drag reduction performance of the heat exchanger core.

Description

Technical Field

[0001] This invention relates to the field of high-efficiency compact heat exchanger technology, and more specifically to a printed circuit board heat exchanger core employing hybrid fins. Background Technology

[0002] Printed circuit board (PCB) heat exchangers are widely used in supercritical carbon dioxide Brayton cycles. PCB heat exchangers can operate reliably for extended periods under extreme conditions, withstanding pressures up to 60 MPa, temperatures up to 1400 °C, and a compact size of up to 1000 m². 2 / m 3 The heat exchange efficiency is as high as 95%; at the same time, under the same heat exchange power conditions, the compactness of the printed circuit board heat exchanger can be improved by more than 85% compared with the shell and tube heat exchanger.

[0003] Existing printed circuit board (PCB) heat exchanger cores primarily employ two fin structures: continuous fins such as straight-through channels, Z-shaped channels, or S-shaped channels; and discontinuous fins such as spindle-shaped fins, airfoil-shaped fins, or S-shaped fins. Compared to continuous fin structures, discontinuous fin structures can effectively suppress the formation of the flow boundary layer, thereby improving core heat transfer performance and reducing fluid flow resistance. However, PCB heat exchanger cores with only one type of fin suffer from insufficient compactness and drag reduction performance. Summary of the Invention

[0004] To address the problems existing in current printed circuit board heat exchangers, the present invention aims to provide a printed circuit board heat exchanger core using hybrid fins. This core employs a hybrid fin design that combines corrugated fins with spindle-shaped fins, thus solving the problems of insufficient compactness and drag reduction performance of existing printed circuit board heat exchanger cores.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A printed circuit board heat exchanger core employing hybrid fins is disclosed. The core is formed by alternating stacking of cold-side heat exchange plates 1 and hot-side heat exchange plates 2. The gap between the cold-side heat exchange plates 1 and hot-side heat exchange plates 2 is formed by cold-side fluid channels 3 and hot-side fluid channels 4, which are distributed alternately, allowing high and low temperature fluids to flow and exchange heat. Multiple rows of corrugated fins 5 and spindle-shaped fins 6 are alternately arranged on the cold-side heat exchange plates 1 and hot-side heat exchange plates 2 along the fluid flow direction. Both the corrugated fins 5 and spindle-shaped fins 6 are discontinuous fins.

[0007] Both sides of the core are cold-side heat exchange plates 1.

[0008] The thickness of the cold-side heat exchange plate 1 and the hot-side heat exchange plate 2 is 1.0 to 2.0 mm.

[0009] The fluid channel height of the cold side fluid channel 3 and the hot side fluid channel 4 is 0.5 to 1.5 mm.

[0010] The wavy fins 5 in the same row are arranged in a straight line along the direction of fluid flow. The chord length of the wavy fins 5 is 6-8 mm, the chord height of the wavy fins 5 is 1.0-2.0 mm, the width of the wavy fins 5 is 0.5-1.0 mm, the spacing between adjacent wavy fins 5 in the same row is 10-15 mm, and the spacing between wavy fins 5 in adjacent rows is 3.0-5.0 mm.

[0011] The spindle-shaped fins 6 in the same row are arranged in a straight line along the direction of fluid flow, and are staggered with the wavy fins 5; the staggered spacing between the spindle-shaped fins 6 and the wavy fins 5 is equal to the fin chord length of the wavy fins 5.

[0012] The length of the spindle-shaped fin 6 is equal to the distance between the tail end of the wavy fin 5 and the head end of another fin; the width of the spindle-shaped fin 6 is 0.5 to 1.0 mm; the distance between the heads of two adjacent spindle-shaped fins 6 in the same row is equal to the sum of the length of the spindle-shaped fin 6 and the chord length of the wavy fin 5.

[0013] Compared with existing printed circuit board type heat exchanger cores, the present invention has the following advantages:

[0014] The hybrid fins described in this invention, employing both corrugated and spindle-shaped fins, effectively suppress boundary layer formation and improve overall heat transfer performance compared to continuous fins. Corrugated fins create secondary eddies at the troughs during fluid flow, enhancing heat transfer, while spindle-shaped fins reduce flow stagnation and lower flow resistance within the flow channel. Furthermore, compared to discontinuous fins of a single type, the turbulence during fluid flow is more intense, effectively enhancing flow heat transfer. The hybrid fins also effectively increase the heat transfer area and improve the compactness of the heat exchanger core. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the main structure of a printed circuit board heat exchanger core using hybrid fins according to the present invention.

[0016] Figure 2 This is a front view of the core structure of a printed circuit board heat exchanger using hybrid fins according to the present invention.

[0017] Figure 3 This is a top view of the core shell of a printed circuit board heat exchanger using hybrid fins according to the present invention.

[0018] Figure 4 This is a schematic diagram of the fin arrangement of a printed circuit board heat exchanger core using hybrid fins according to the present invention.

[0019] In the diagram: L - plate thickness; H - fluid channel height; L c1 -Wave-shaped fin chord length; L h1 - Spacing between adjacent wavy fins in the same row; L t1 - Width of the wavy fins; L v - Spacing between adjacent rows of wavy fins; L s -Wave-shaped fin chord height; L c2 - Length of the spindle-shaped fins; L h2 - The distance between the tips of two adjacent spindle-shaped fins in the same row; L t2 - Spindle-shaped fin width; 1- Cold side heat exchange plate; 2- Hot side heat exchange plate; 3- Cold side fluid channel; 4- Hot side fluid channel; 5- Corrugated fin; 6- Spindle-shaped fin. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0021] like Figure 1 As shown, this invention is a printed circuit board heat exchanger core employing hybrid fins. The core is formed by alternating stacking of cold-side heat exchange plates 1 and hot-side heat exchange plates 2. The gap between the cold-side heat exchange plates 1 and hot-side heat exchange plates 2 forms a cold-side fluid channel 3 and a hot-side fluid channel 4, which are distributed alternately, allowing high and low temperature fluids to flow and exchange heat within them. Multiple rows of corrugated fins 5 and spindle-shaped fins 6 are alternately arranged on both the cold-side heat exchange plates 1 and hot-side heat exchange plates 2 along the fluid flow direction; both types of fins are discontinuous.

[0022] like Figure 1 As shown, preferably, both sides of the core are cold-side heat exchange plates (1). This arrangement of heat exchange plates helps to prevent heat from being lost from the inside of the heat exchanger core to the external environment.

[0023] like Figure 2 As shown, the plate thickness L of the cold-side heat exchange plate 1 and the hot-side heat exchange plate 2 is 1.0–2.0 mm. The fluid channel height H of the cold-side fluid channel 3 and the hot-side fluid channel 4 is 0.5–1.5 mm. This plate thickness helps reduce the thermal resistance between the cold and hot fluids and ensures the pressure-bearing capacity of the heat exchanger core. This fluid channel height helps ensure the uniformity of the velocity and temperature distribution of the fluid in the direction perpendicular to the fluid flow.

[0024] like Figure 3 and Figure 4 As shown, the same row of corrugated fins 5 are arranged in a straight line along the fluid flow direction. This arrangement can increase vortex disturbance during fluid flow and suppress the increase in flow resistance. The chord length L of the corrugated fins is...c1 The chord height L of the wavy fins is 6-8 mm. s The diameter is 1.0–2.0 mm, and the width L of the wavy fins is... t1 The spacing L between adjacent wavy fins in the same row is 0.5–1.0 mm. h1 The spacing L between adjacent rows of wavy fins is 10-15 mm. v The diameter is 3.0–5.0 mm. The wavy fins have no staggered spacing. This fin chord length and height helps to improve the heat transfer intensity of the core while minimizing the increase in flow resistance within the flow channel. This fin width helps to ensure the intensity of fluid flow disturbance and increase the total heat transfer area within the core.

[0025] like Figure 3 and Figure 4 As shown, the spindle-shaped fins 6 are arranged in a straight line along the fluid flow direction, which helps reduce resistance loss. They are staggered with the corrugated fins 5, which guides the fluid flow towards the corrugated fins on both sides when it passes over the spindle-shaped fins, thus improving the core's heat transfer capacity. The staggered spacing between the spindle-shaped fins 6 and the corrugated fins 5 is equal to the fin chord length L of the corrugated fins 5. c1 This helps to suppress backflow when fluid flows through two types of fins simultaneously, and reduces pressure drop in the flow direction.

[0026] like Figure 4 As shown, the fin length L of the spindle-shaped fin 6 is... c2 The distance between the tail end of the wavy fin 5 and the head end of another fin is equal to the distance between the tail end of the fin and the head end of the other fin. Using this dimension helps to avoid backflow during fluid flow and improves the compactness of the core. The fin width L of the spindle-shaped fin 6 is... t2 The distance is 0.5–1.0 mm. The spacing L between the heads of two adjacent spindle-shaped fins in the same row is... h2 The fin length L is equal to the spindle-shaped fin 6. c2 The chord length L of the wavy fin 5 c1 The sum of these two dimensions allows for a denser fin arrangement while reducing pressure loss, thus increasing the heat exchange area and heat exchange intensity.

[0027] Working principle: such as Figures 1-4 As shown, when high and low temperature fluids flow and exchange heat in the hot-side fluid channel 4 and the cold-side fluid channel 3 respectively, the corrugated fins can create secondary vortices at the troughs during fluid flow to enhance heat transfer, while the spindle-shaped fins can reduce flow stagnation and decrease flow resistance. Simultaneously, compared to single-type discontinuous fins, the turbulence during fluid flow is more intense, effectively enhancing flow heat transfer. Using hybrid fins can effectively increase the heat exchange area and improve the compactness of the heat exchanger core.

Claims

1. A printed circuit board heat exchanger core employing hybrid fins, characterized in that: The core is formed by alternating stacking of cold-side heat exchange plates (1) and hot-side heat exchange plates (2); the gap between the cold-side heat exchange plates (1) and the hot-side heat exchange plates (2) is the cold-side fluid channel (3) and the hot-side fluid channel (4), and the cold-side fluid channel (3) and the hot-side fluid channel (4) are distributed alternately, and high and low temperature fluids flow and exchange heat in them; multiple rows of wavy fins (5) and spindle fins (6) are arranged alternately on the cold-side heat exchange plates (1) and the hot-side heat exchange plates (2) along the fluid flow direction, and the wavy fins (5) and the spindle fins (6) are both discontinuous fins; The same row of corrugated fins (5) are arranged in a straight line along the direction of fluid flow. The chord length of the corrugated fins (5) is 6-8 mm, the chord height of the corrugated fins (5) is 1.0-2.0 mm, the width of the corrugated fins (5) is 0.5-1.0 mm, the spacing between adjacent corrugated fins (5) in the same row is 10-15 mm, and the spacing between corrugated fins (5) in adjacent rows is 3.0-5.0 mm. The spindle-shaped fins (6) in the same row are arranged in a straight line along the direction of fluid flow, and are arranged in a staggered line with the wavy fins (5); the staggered spacing between the spindle-shaped fins (6) and the wavy fins (5) is equal to the fin chord length of the wavy fins (5). The length of the spindle-shaped fin (6) is equal to the distance between the tail end of the wavy fin (5) and the head end of another fin; the width of the spindle-shaped fin (6) is 0.5 to 1.0 mm; the distance between the heads of two adjacent spindle-shaped fins (6) in the same row is equal to the sum of the length of the spindle-shaped fin (6) and the chord length of the wavy fin (5).

2. The printed circuit board heat exchanger core with hybrid fins according to claim 1, characterized in that: Both sides of the core are cold-side heat exchange plates (1).

3. The printed circuit board heat exchanger core with hybrid fins according to claim 1, characterized in that: The thickness of the cold-side heat exchange plate (1) and the hot-side heat exchange plate (2) is 1.0 to 2.0 mm.

4. The printed circuit board heat exchanger core with hybrid fins according to claim 1, characterized in that: The fluid channel height of the cold side fluid channel (3) and the hot side fluid channel (4) is 0.5 to 1.5 mm.

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