Semi-capsule-shaped convex finned tube type heat exchanger

Abstract

The invention provides a semi-capsule-shaped convex finned tube heat exchanger which is mainly used for cooling lubricating oil in an aero-engine and comprises a heat exchanger body, and the heat exchanger body comprises an oil collecting cavity, a coiled pipe and semi-capsule-shaped convex fins with the distribution density from low to high. The flowing mode of the heat exchanger is reverse flow, air flows through the sides, with low distribution density, of the semi-capsule-shaped protruding fins, and lubricating oil flows into the coiled pipe from the oil collecting cavity in the side, with high distribution density, of the semi-capsule-shaped protruding fins. The fins are fixed to the coiled pipe, the semi-capsule-shaped protrusions on the fins can intensify disturbance of the air side of the heat exchanger so as to increase the heat exchange coefficient of the air side, meanwhile, the heat exchange area of the fins is increased to a certain degree, and the distribution density is increased from low to high so that the heat exchange coefficient can be increased with small pressure drop loss. According to the heat exchanger, lubricating oil of the aero-engine can be efficiently cooled with small pressure drop loss.

Description

Technical Field

[0001] The invention relates to the technical field of efficient cooling of aviation engine lubricating oil, in particular to a semi-capsule-shaped raised fin-tube heat exchanger. Background Art

[0002] The lubricating oil system is an important part of the aircraft engine. In order to ensure the lubrication and cooling of the mechanical parts of the aircraft engine, the operating temperature range of the lubricating oil must be controlled. At present, the temperature of the main lubricating oil of the engine of advanced aircraft is close to the limit of the existing lubricating oil use temperature, and the fuel and lubricating oil can only have limited heat exchange, so it is necessary to design a heat exchanger to cool the lubricating oil with external air when the lubricating oil temperature is high.

[0003] In order to further improve the heat transfer performance of the tube-fin heat exchanger, a method of punching out convexities on the fins is adopted to enhance the heat transfer coefficient on the air side. Different forms of convexities have different effects on the heat transfer effect. It is very important to research and develop a reasonable convex form in combination with existing technologies. The convex form must have the following characteristics: strong disturbance to the fluid while having little obstruction to the flow and the outer edge of the convexity must be smooth, so that it can enhance heat transfer without increasing too much flow resistance and is more wear-resistant and has a long service life. Summary of the invention

[0004] In order to solve the problems of the prior art, the present invention provides a semi-capsule-shaped protrusion type fin-tube heat exchanger, which adopts a unique semi-capsule-shaped protrusion design to enhance the disturbance of air circulation and strengthen the heat exchange effect on the air side. At the same time, the outer edge of the semi-capsule-shaped protrusion is relatively smooth, which can reduce wear and extend service life.

[0005] The present invention provides a semi-capsule-shaped raised fin-tube heat exchanger, comprising a heat exchanger body, the heat exchanger body comprising an oil collecting chamber, a serpentine tube, and semi-capsule-shaped raised fins; the oil collecting chamber comprises a lubricating oil inlet collecting chamber and a lubricating oil outlet collecting chamber; the serpentine tube is connected to the lubricating oil inlet collecting chamber and the lubricating oil outlet collecting chamber one by one; the semi-capsule-shaped raised fins are fixedly connected to the serpentine tube, and air flows on both sides of the semi-capsule-shaped raised fins. By adopting the above technical solution, the lubricating oil in the aircraft engine is cooled by using the outer duct air with a lower temperature, which can achieve higher heat exchange efficiency and upper limit.

[0006] As a further improvement, the semi-capsule-shaped protrusion-type fin includes a substrate and a semi-capsule-shaped protrusion structure distributed in an array on the substrate.

[0007] As a further improvement, the distribution density of the semi-capsule-shaped protrusion structures is from low to high along the air flow direction.

[0008] As a further improvement, the protrusion length of the semi-capsule-shaped protrusion structure is one third of the distance between the centers of the serpentine tubes, the width is half of the outer diameter of the serpentine tubes, and the height is one third of the spacing between the substrates.

[0009] As a further improvement, the lubricating oil inlet collecting chamber is arranged on a side of the semi-capsule-shaped protrusion-type fin where the density of semi-capsule-shaped protrusions is high, while the lubricating oil outlet collecting chamber is arranged on a side of the semi-capsule-shaped protrusion-type fin where the density of semi-capsule-shaped protrusions is low.

[0010] As a further improvement, the serpentine tubes are arranged in a sequential manner, and the internal circulating medium is lubricating oil, which flows into the lubricating oil inlet collecting chamber and flows out of the lubricating oil outlet collecting chamber.

[0011] As a further improvement, the medium flowing outside the serpentine tube is air, and the heat exchanger body is placed in the outer duct of the aircraft engine.

[0012] The beneficial effects of the present invention are: 1. Placing the heat exchanger in the outer duct to use the low-temperature air in the outer duct to cool the lubricating oil in the aircraft engine and the flow mode is countercurrent, which can obtain higher heat exchange efficiency and heat exchange upper limit.

[0013] 2. The unique semi-capsule-shaped protrusion design enhances the disturbance of air circulation and strengthens the heat exchange effect on the air side. At the same time, the outer edge of the semi-capsule-shaped protrusion is smoother, which can reduce wear and extend service life.

[0014] 3. The semi-capsule-shaped protrusions are distributed in a density from low to high along the air flow direction, which can enhance heat exchange without increasing too much flow resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 It is a schematic diagram of the overall structure of the heat exchanger according to an embodiment of the present invention.

[0017] Figure 2 4 is a top view of a semi-capsule-shaped raised fin according to an embodiment of the present invention.

[0018] Figure 3 yes Figure 2 Cross-section along line AA.

[0019] Figure 4 yes Figure 2 Cross-section along line BB.

[0020] In the figure: 1 heat exchanger body; 11-oil collecting chamber; 111-lubricating oil inlet collecting chamber; 112-lubricating oil outlet collecting chamber; 12-serpentine tube; 13-semi-capsule-shaped protruding fin; 131-base plate; 132-semi-capsule-shaped protrusion. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] The present application discloses a semi-capsule-shaped raised tube-fin heat exchanger suitable for aircraft engines. Figure 1 The invention discloses a semi-capsule-shaped raised tube-fin heat exchanger suitable for aircraft engines, wherein the heat exchanger body 1 comprises an oil collecting chamber 11, a serpentine tube 12 and semi-capsule-shaped raised fins 13.

[0023] The oil collecting chamber 11 includes a lubricating oil inlet collecting chamber 111 and a lubricating oil outlet collecting chamber 112; the preferred number of the serpentine tubes 12 is 13; the semi-capsule-shaped protrusion-type fin 13 includes a substrate 131 and semi-capsule-shaped protrusions 132 with different distribution densities on the substrate 131, which are fixed on the serpentine tubes 12.

[0024] There are 6 semi-capsule-shaped raised fins 13, which are evenly distributed on the serpentine tube 12, and the 6 semi-capsule-shaped raised fins 13 are fixedly connected to the corresponding serpentine tube 12; the two ends of each serpentine tube 12 are respectively connected to the lubricating oil inlet collecting chamber 111 and the lubricating oil outlet collecting chamber 112.

[0025] Lubricating oil flows inside the serpentine tube 12; the lubricating oil inlet collecting chamber 111 is set on the side of the semi-capsule-shaped protrusion 132 with high distribution density in the semi-capsule-shaped protrusion type fin 13, and the lubricating oil outlet collecting chamber 112 is set on the side of the semi-capsule-shaped protrusion 132 with low distribution density in the semi-capsule-shaped protrusion type fin 13.

[0026] The distribution density of the semi-capsule-shaped protrusions 132 on the semi-capsule-shaped protrusion fin 13 is from low to high along the air flow direction, and based on the upper surface of the substrate 131, the length of the semi-capsule-shaped protrusion 132 is one-third of the center distance of the serpentine tube 12, the width is half of the outer diameter of the serpentine tube 12, and the height is one-third of the spacing of the substrate 131.

[0027] The semi-capsule-shaped protrusions 132 are distributed along the air flow direction from low to high density on the substrate 131, and their long sides are perpendicular to the air flow direction. The unique design of the semi-capsule-shaped protrusions 132 enhances the disturbance of air circulation and the heat exchange effect on the air side. At the same time, the outer edge of the semi-capsule-shaped protrusions 132 is relatively smooth, which can reduce wear and extend the service life. The semi-capsule-shaped protrusions 132 are distributed along the air flow direction from low to high density, which can enhance heat exchange without increasing too much flow resistance.

[0028] During the process of starting the cooling system, the lubricating oil flows into the serpentine tube 12 from the lubricating oil inlet collecting chamber 111 and flows out from the lubricating oil outlet collecting chamber 112. The duct air flows from the side with low distribution density of the semi-capsule-shaped protrusions 132 in the semi-capsule-shaped protrusion-shaped fins 13 outside the serpentine tube 12 to the side with high distribution density, flushing the heat exchanger body 1. By flushing the semi-capsule-shaped protrusion-shaped fin tubes with duct air, efficient heat exchange of the lubricating oil in the aircraft engine is achieved, the temperature of the lubricating oil is reduced, so that more components in the aircraft engine can be cooled, and the service life of the aircraft engine is extended.

[0029] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, the above is only a preferred embodiment of the present invention. Since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field is within the technical scope disclosed by the present invention. For ordinary technicians in the technical field, changes or replacements that can be easily thought of should be covered within the protection scope of the present invention without departing from the principle of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A semi-capsule convex fin-tube heat exchanger, characterized in that: It includes a heat exchanger body, which includes an oil collecting chamber, a serpentine tube, and semi-capsule-shaped protruding fins; the oil collecting chamber includes a lubricating oil inlet collecting chamber and a lubricating oil outlet collecting chamber; the serpentine tube is connected to the lubricating oil inlet collecting chamber and the lubricating oil outlet collecting chamber one by one; the semi-capsule-shaped protruding fins are fixedly connected to the serpentine tube, and air flows on both sides of the semi-capsule-shaped protruding fins.

2. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 1 is characterized in that: The semi-capsule-shaped protruding fin comprises a substrate and a semi-capsule-shaped protruding structure distributed in an array on the substrate.

3. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 2 is characterized in that: The distribution density of the semi-capsule-shaped protrusion structures is from low to high along the air flow direction.

4. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 2, characterized in that: The protrusion length of the semi-capsule-shaped protrusion structure is one third of the center distance of the serpentine tube, the width is half of the outer diameter of the serpentine tube, and the height is one third of the substrate spacing.

5. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 2 or 3, characterized in that: The lubricating oil inlet collecting chamber is arranged on the side of the semi-capsule-shaped protrusion-type fin with high distribution density of the semi-capsule-shaped protrusions, while the lubricating oil outlet collecting chamber is arranged on the side of the semi-capsule-shaped protrusion-type fin with low distribution density of the semi-capsule-shaped protrusions.

6. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 1, characterized in that: The serpentine tubes are arranged in a sequential manner, and the internal flow medium is lubricating oil, which flows into the lubricating oil inlet collecting chamber and flows out of the lubricating oil outlet collecting chamber.

7. The semi-capsule-shaped raised fin-tube heat exchanger according to claim 1, characterized in that: The medium flowing outside the serpentine tube is air, and the heat exchanger body is placed in the outer duct of the aircraft engine.

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