An air compressor waste heat recovery device and method

Abstract

This invention relates to the field of energy saving and waste heat recovery technology for air compressors, specifically to a waste heat recovery device and method for air compressors. It includes a heat exchange shell, a thick-walled heat exchange tube, a micro-jet oscillator array, a pneumatic proportional valve, an antagonistic corrugated prestressed energy storage chamber, and a control system. The system divides the heat exchange shell into hot and cold side channels, and combines the control valve and jet array for air-water heat exchange. Its core is to utilize the antagonistic corrugated prestressed energy storage chamber to absorb and transfer the high-frequency pressure pulsation energy in the hot-side channel. When the hot-side pressure is at its peak, it absorbs the peak kinetic energy to protect the heat exchange tube. Simultaneously, the chamber synchronously squeezes towards the cold-side channel, forcing a dramatic increase in cooling water flow velocity, forming a scouring jet on the outer wall of the tube to enhance heat exchange. This invention cleverly combines resistance to pulsation impact and enhanced cold-side heat exchange in the same device, effectively extending the device's service life and significantly improving waste heat recovery efficiency.

Description

Technical Field

[0001] This invention relates to the field of energy saving and waste heat recovery technology for air compressors, specifically to a waste heat recovery device and method for air compressors. Background Technology

[0002] In the operating environment of an air compressor, the exhaust side continuously outputs a high-temperature oil-gas mixture with high-frequency pressure pulsation. To recover this waste heat, existing equipment typically introduces the oil-gas mixture directly into a heat exchanger to exchange heat with the cooling medium. Current solutions generally use thin-walled heat exchange tubes or structures that simply change the shape of the flow channel for waste heat recovery. Due to the reliance on the above single physical structure, on the one hand, the high-frequency pulsating high-pressure fluid is prone to causing structural fatigue failure of the thin-walled tube, lacking an effective mechanism for pulsating energy transfer and absorption; on the other hand, high-viscosity oil films are prone to adhere to the inner wall of the tube and cause early coking, resulting in thickening of the thermal boundary layer and a sharp increase in heat transfer resistance. In addition, to monitor the actual heat exchange state, existing technologies often require the installation of temperature probes or deposition thickness sensors in a high-temperature oil-containing environment. These detection elements are easily affected by oil contamination and fail, making it difficult to provide stable measurement and control data, resulting in the system being unable to dynamically turbulent and regulate the fluid based on the actual resistance within the tube.

[0003] Therefore, how to balance high-frequency shock resistance and adaptive thermal boundary layer reduction in the same structure, and accurately characterize heat transfer resistance and achieve precise control of cleaning energy in the absence of internal micro-measuring elements, has become an urgent technical problem to be solved. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the present invention provides a waste heat recovery device and method for air compressors. Specifically, the technical solution of the present invention is as follows: A waste heat recovery device for an air compressor, comprising: A heat exchange housing is connected to a cooling water outlet pipe. The interior of the heat exchange housing is divided into a hot side channel and a cold side channel by a fixed partition. The air inlet of the heat exchange housing is connected to the exhaust pipe of an air compressor. Heat exchange thick-walled tubes are arranged in parallel inside the hot-side channel. The two ends of the heat exchange thick-walled tubes are respectively welded to the fixed partition. The outer wall of the heat exchange thick-walled tubes contacts the cooling water introduced into the cold-side channel. A micro jet oscillator array is fixedly connected to the heat exchange housing and leads to a nozzle. The nozzle is directly opposite the inner hole of the heat exchange thick-walled tube. The micro jet oscillator array is connected to a high-pressure exhaust bypass pipe. A pneumatic proportional valve is disposed between the high-pressure exhaust bypass pipe and the micro jet oscillator array; An antagonistic corrugated prestressed energy storage chamber is disposed between the fixed partition and the side wall of the heat exchange shell. The hot side end face of the antagonistic corrugated prestressed energy storage chamber is exposed to the air inlet end of the hot side channel, and the cold side end face of the antagonistic corrugated prestressed energy storage chamber extends to the cooling water inlet of the cold side channel. The control system controls the pneumatic proportional valve based on instantaneous pressure data.

[0005] As a further embodiment of the present invention, the interior of the heat exchange shell is divided into an air inlet confluence area, a heat exchange core area, and an exhaust confluence area by a first fixed partition and a second fixed partition. The intake manifold and the exhaust manifold constitute the hot-side channel, and the heat exchange core area constitutes the cold-side channel.

[0006] As a further aspect of the present invention, the main body of the antagonistic corrugated prestressed energy storage chamber is a corrugated stainless steel elastic bladder. The stainless steel elastic bladder is filled with an inert gas.

[0007] As a further embodiment of the present invention, the pressure-bearing end face of the stainless steel elastic bladder faces the incoming flow direction of the air intake confluence area, and the working end face of the stainless steel elastic bladder passes through the reserved hole on the first fixed partition and extends into the cooling water inlet of the cold side channel.

[0008] As a further embodiment of the present invention, pressure sensors are respectively provided in the intake manifold and the exhaust manifold, the pressure sensors are connected to the control system, and the pressure sensors are used to obtain instantaneous pressure data.

[0009] As a further aspect of the present invention, the micro jet oscillator array includes uniformly distributed fluid oscillation cavities. The output nozzle of the fluid oscillation chamber is directly opposite the inlet center of the adjacent heat exchange thick-walled tube.

[0010] A control method for an air compressor waste heat recovery device includes: S1. Real-time acquisition of instantaneous pressure data at the inlet and outlet of the hot side channel; S2. Based on the instantaneous pressure data at the intake end, extract the amplitude of the first high-frequency harmonic component of the intake end pressure signal of the hot side channel; S3. Based on the instantaneous pressure data at the outlet, extract the amplitude of the second high-frequency harmonic component of the pressure signal at the outlet of the hot side channel; S4. Calculate the difference between the amplitude of the first high-frequency harmonic component and the amplitude of the second high-frequency harmonic component; S5. Divide the difference by the amplitude of the first high-frequency harmonic component to calculate the high-frequency pulse attenuation rate.

[0011] As a further aspect of the present invention, step S5 is followed by: S601. Obtain the upper limit value of the reference error envelope pre-constructed based on the calibration conditions, and compare the calculated high-frequency pulse attenuation rate with the upper limit value of the reference error envelope; S602. If the high-frequency pulse attenuation rate is greater than the upper limit of the reference error envelope, then control the pneumatic proportional valve to increase its opening and increase the bypass airflow pulse width that drives the micro jet oscillator array. S603. Use the jet generated by the micro jet oscillator array to strip away the fluid boundary layer inside the heat exchange thick-walled tube. S604. If the high-frequency pulse attenuation rate is less than or equal to the upper limit of the reference error envelope, then maintain the current opening of the pneumatic proportional valve.

[0012] As a further aspect of the present invention, step S603 is followed by: S701. Obtain the median of the reference error envelope pre-constructed based on the calibration conditions, and continuously calculate to obtain a new high-frequency pulse attenuation rate; S702. Compare the new high-frequency pulse attenuation rate with the median of the reference error envelope; S703. If the new high-frequency pulse attenuation rate is less than the median of the reference error envelope, then control the pneumatic proportional valve to reduce its opening and reduce the excitation energy of the micro jet oscillator array. S704. If the new high-frequency pulse attenuation rate is greater than or equal to the median of the reference error envelope, then the increased opening state of the pneumatic proportional valve is maintained.

[0013] As a further aspect of the present invention, step S1 is preceded by: S01. Obtain pressure pulsation data in the hot side channel. When the pressure pulsation data is at a peak, the antagonistic corrugated prestressed energy storage chamber is compressed and absorbs the peak kinetic energy of the pulsation. S02. The working end of the antagonistic corrugated prestressed energy storage chamber is squeezed into the cold side channel, which forces the incoming cooling water to increase its flow rate and form a scouring jet on the outer wall of the heat exchange thick-walled tube.

[0014] The present invention has the following beneficial effects: 1. This invention absorbs and transfers high-frequency pressure pulsation energy within the hot-side channel by setting up an antagonistic corrugated prestressed energy storage chamber. When the hot-side pressure is at its peak, the chamber absorbs the peak kinetic energy under pressure, protecting the thick-walled heat exchange tube from fatigue damage. Simultaneously, the working end of the chamber compresses the interior of the cold-side channel, forcing a sharp increase in cooling water velocity and forming a scouring jet on the outer wall of the thick-walled heat exchange tube to enhance heat transfer. This structure combines resistance to pulsation impact and enhanced cold-side heat transfer within the same device, effectively extending the device's lifespan and improving waste heat recovery efficiency.

[0015] 2. This invention calculates the high-frequency pulse attenuation rate by acquiring instantaneous pressure data at the inlet and outlet, eliminating the need for easily failing built-in detection probes in high-temperature, oil-containing environments, thus accurately assessing the thickening state of the boundary layer inside thick-walled heat exchange tubes. Combined with a preset reference error envelope, the control system dynamically adjusts the pneumatic proportional valve, utilizing a jet generated by a micro-jet oscillator array to precisely strip away the fluid boundary layer inside the tube. This control method achieves macroscopic quantification of the internal stagnation state and precise on-demand control of cleaning energy, avoiding ineffective energy consumption and ensuring long-term, efficient heat transfer. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the overall external structure of the device; Figure 2 This is a schematic diagram of the cross-sectional structure of the heat exchange shell; Figure 3 This is a schematic diagram of a pneumatic proportional valve and its connection structure; Figure 4 This is a flowchart of the method of the present invention.

[0017] In the diagram: 1. Heat exchange shell; 2. Cooling water outlet pipe; 3. Fixed baffle; 4. Hot side channel; 5. Cold side channel; 6. Air compressor exhaust pipe; 7. Heat exchange thick-walled tube; 8. Micro jet oscillator array; 9. Nozzle; 10. High-pressure exhaust bypass pipe; 11. Pneumatic proportional valve; 12. Antagonistic corrugated prestressed energy storage chamber; 13. Control system; 14. First fixed baffle; 15. Second fixed baffle; 16. Inlet manifold; 17. Heat exchange core area; 18. Exhaust manifold; 19. Stainless steel elastic bladder; 20. Pressure-bearing end face; 21. Working end face; 22. Reserved hole; 23. Pressure sensor; 24. Fluid oscillation chamber; 25. Air supply inlet; 26. Feedback channel; 27. Oscillation main chamber; 28. Output nozzle. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] Example 1: A waste heat recovery device for an air compressor, comprising: Combination Figure 1 and Figure 2 As shown, the heat exchange housing 1 is connected to a cooling water outlet pipe 2. The interior of the heat exchange housing 1 is divided into a hot side channel 4 and a cold side channel 5 by a fixed partition 3. The air inlet end of the heat exchange housing 1 is connected to the air compressor exhaust pipe 6. The heat exchange thick-walled tubes 7 are arranged in parallel inside the hot side channel 4. The two ends of the heat exchange thick-walled tubes 7 are welded to the fixed partition 3 respectively. The outer wall of the heat exchange thick-walled tubes 7 contacts the cooling water introduced into the cold side channel 5. Combination Figure 3 As shown, the micro jet oscillator array 8 is fixedly connected to the heat exchange housing 1 and leads to the nozzle 9. The nozzle 9 is directly opposite the inner hole of the heat exchange thick-walled tube 7. The micro jet oscillator array 8 is connected to the high-pressure exhaust bypass pipe 10. A pneumatic proportional valve 11 is disposed between the high-pressure exhaust bypass pipe 10 and the micro jet oscillator array 8; The antagonistic corrugated prestressed energy storage chamber 12 is disposed between the fixed partition 3 and the side wall of the heat exchange shell 1. The hot side end face of the antagonistic corrugated prestressed energy storage chamber 12 is exposed to the air inlet end of the hot side channel 4, and the cold side end face of the antagonistic corrugated prestressed energy storage chamber 12 extends to the cooling water inlet of the cold side channel 5. Control system 13 controls pneumatic proportional valve 11 based on instantaneous pressure data; The high-temperature oil-gas mixture discharged from the air compressor flows into the hot-side channel 4 of the heat exchange shell 1. The heat exchange shell 1 adopts a pressure-resistant metal shell structure, preferably a carbon steel shell or a stainless steel shell. The shell design pressure can be 1.6MPa to 4.0MPa, and the design temperature can be 120℃ to 220℃ to adapt to the fluctuating operating conditions of the exhaust side of the oil-injected screw air compressor. The fixed partition 3 is used to stably divide the inside of the shell into the hot-side channel 4 and the cold-side channel 5. The fixed partition 3 and the heat exchange shell 1 are connected by full penetration welding or sealing gasket compression to avoid oil and water leakage. The heat exchange thick-walled tube 7 is set in the hot side channel 4 and welded to the fixed partition 3 to form a pressure-bearing skeleton. The thick wall means that when there is high-frequency pressure pulsation in the tube, the tube wall thickness is increased compared with the conventional thin-walled heat exchange tube, so as to obtain the circumferential stiffness and fatigue life that meet the pressure design threshold. In this embodiment, a seamless steel tube with a wall thickness of 2mm to 5mm can be used, and the outer wall directly exchanges heat with the cooling water in the cold side channel 5. The micro jet oscillator array 8 obtains part of the high-pressure gas through the high-pressure exhaust bypass pipe 10 and generates a self-excited jet with the help of the internal oscillation cavity, so that the nozzle 9 outlet forms a periodic pulsating jet and is directly facing the inlet of the heat exchange thick-walled tube 7. The pulsating jet builds a local acoustic-fluid coupling effect in the inlet area of ​​the thick-walled tube, weakening the oil film adhesion and the tendency of thermal boundary layer thickening. The pneumatic proportional valve 11 is used to continuously adjust the bypass air volume, with an opening range of 5% to 100% and a control resolution of less than 1%, to achieve graded control of the excitation energy of the micro jet oscillator array 8. The antagonistic corrugated prestressed energy storage chamber 12 is located between the fixed partition 3 and the side wall of the heat exchange shell 1. The hot side end face directly bears the pressure pulsation at the air inlet of the hot side channel 4, and the cold side end face extends to the cooling water inlet. When the pulsating pressure on the hot side increases, the chamber undergoes elastic deformation and squeezes the cold side inlet water flow, causing the cooling water to accelerate instantaneously in a local area, thereby improving the scouring and heat exchange capacity of the outer wall of the heat exchange thick-walled tube 7. The control system 13 is electrically connected to the pneumatic proportional valve 11 or connected by pneumatic-electric conversion. The control system 13 can be composed of an industrial controller, a pressure acquisition module, and a valve position output module, and is used to adjust the bypass air volume according to the inlet and outlet pressure characteristics. Compared to waste heat recovery equipment that relies solely on thin-walled heat exchange tubes or simply changes the flow channel shape, this device uses thick-walled heat exchange tubes 7 to bear pressure, micro jet oscillator arrays 8 to reduce boundary layer, and antagonistic corrugated prestressed energy storage chambers 12 to transfer pulsating energy, thus achieving both heat-side anti-pulsation capability and cold-side heat exchange enhancement capability in the same structure.

[0020] The interior of the heat exchange shell 1 is divided into an air inlet confluence area 16, a heat exchange core area 17 and an exhaust confluence area 18 by a first fixed partition 14 and a second fixed partition 15. The air inlet confluence area 16 and the exhaust confluence area 18 form a hot side channel 4, and the heat exchange core area 17 forms a cold side channel 5. To ensure that the hot-side pulsating fluid has a stable confluence space before entering the heat exchange thick-walled tube 7 and an independent discharge space after leaving the heat exchange thick-walled tube 7, a first fixed baffle 14 and a second fixed baffle 15 are provided inside the heat exchange shell 1. The two baffles divide the internal space into an inlet confluence area 16, a heat exchange core area 17 and an exhaust confluence area 18 in sequence. The inlet confluence area 16 is located on the side of the air compressor exhaust inlet. Its function is to receive the high-temperature oil-gas mixture from the exhaust main pipeline and provide a relatively uniform inlet pressure distribution for each heat exchange thick-walled tube 7. Preferably, its axial length is 0.6 to 1.5 times the inner diameter of the shell. The exhaust manifold 18 is located at the outlet end. Its function is to collect the fluid discharged from each heat exchange thick-walled tube 7 and guide it to the subsequent pipeline. Preferably, its axial length is 0.5 to 1.2 times the inner diameter of the shell. The heat exchange core area 17 is located between the first fixed partition 14 and the second fixed partition 15. A cold side channel 5 is formed inside. Cooling water flows around the heat exchange thick-walled tube 7 in this area and absorbs heat. The first fixed partition 14 is provided with a reserved hole 22 for the working end face 21 of the corrugated prestressed energy storage chamber to penetrate. Since the intake manifold 16 and the exhaust manifold 18 are separated from the heat exchange core area 17 by the fixed partition 3, the hot side oil-gas mixture only flows inside the heat exchange thick-walled tube 7, and the cooling water only contacts the outer wall of the heat exchange thick-walled tube 7 in the heat exchange core area 17. The two media do not mix directly. This partitioned structure makes the hot-side flow organization and the cold-side flow organization independent of each other, which facilitates the arrangement of pressure sensing, jet excitation and corrugated energy storage components in appropriate areas. It also allows pressure pulsations to be identified and utilized in the intake manifold 16, heat transfer to be completed in the heat exchange core 17, and attenuation characteristics to be read in the exhaust manifold 18, thus providing a stable spatial basis for subsequent control methods based on differential pressure signals.

[0021] The main body of the antagonistic corrugated prestressed energy storage chamber 12 is a corrugated stainless steel elastic bladder 19, wherein the interior of the stainless steel elastic bladder 19 is filled with inert gas. The antagonistic corrugated prestressed energy storage chamber 12 uses a corrugated stainless steel elastic bladder 19 as the main body. The corrugation refers to the formation of multiple continuous peaks and troughs on the bladder wall along the direction of force to provide repeatable elastic deformation capability within a limited displacement. The stainless steel material is preferably 316 stainless steel, 316L stainless steel or corrosion-resistant nickel-based alloy. Among them, 316 stainless steel takes into account oil resistance, heat resistance and formability, and is suitable for long-term exposure in the interface area between oily gas and cooling water. The elastic bladder can be formed by stamping and circumferentially welding multiple layers of thin sheets. The thickness of a single layer can be 0.08 mm to 0.30 mm, and the total number of layers can be 2 to 6, so as to obtain the required axial compliance while ensuring fatigue life. The bladder is filled with an inert gas, which can be nitrogen, argon or helium, with nitrogen being preferred. The pre-filling pressure can be set to 1.05 to 1.50 times the static pressure of the cooling water inlet, so that the bladder maintains a predetermined initial shape when there is no pulsation peak and generates controllable compression displacement when there is a pulsation peak. The inert gas setting allows the gas chamber to absorb transient kinetic energy as a compressible medium under the impact of high-temperature oil-gas mixture, avoiding rigid collisions with the metal bladder. At the same time, the pre-charge pressure generates a reverse restoring force, ensuring that the bladder returns to its original position after the pulsation subsides. Compared with structures that only use rubber bladders or solid springs, this structure can maintain stable elastic properties under the above-mentioned design temperature and oil-containing environment, and does not introduce the risk of rubber aging and shedding causing pollution to the oil and water circuits.

[0022] The pressure-bearing end face 20 of the stainless steel elastic bladder 19 faces the incoming flow direction of the air intake confluence area 16, and the working end face 21 of the stainless steel elastic bladder 19 passes through the reserved hole 22 on the first fixed partition plate 14 and extends into the cooling water inlet of the cold side channel 5. The stainless steel elastic bladder 19 is arranged along the direction from the hot side to the cold side, and its pressure-bearing end face 20 faces the incoming flow direction of the intake manifold 16, so that the pressure wave peak in the high-temperature oil-gas mixture on the hot side can directly act on the end face; the projected area of ​​the pressure-bearing end face 20 is preferably 80mm² to 800mm². If the projected area of ​​the pressure-bearing end face is lower than the set lower limit, the amount of pulsating kinetic energy absorbed will be lower than the design requirements. If the projected area of ​​the pressure-bearing end face is higher than the set upper limit, the flow uniformity in the intake manifold 16 will be reduced. The working end face 21 passes through the reserved hole 22 on the first fixed partition plate 14 and extends into the cooling water inlet of the cold side channel 5. A metal sealing ring, a flexible graphite seal, or a laser welding seal structure is provided between the reserved hole 22 and the outer periphery of the bladder to ensure the isolation between the hot side and the cold side. The distance from which the working end face 21 extends into the cooling water inlet can be 2mm to 20mm, so that it can change the local flow cross-sectional area of ​​the cooling water inlet when the pulsation peak occurs. The so-called working end face 21 refers to the end of the bladder that is subjected to pressure and displacement and is transferred to the cold side fluid. When the pulsation on the hot side increases, this end face advances towards the cold side, locally compresses the water flow and forms a transient acceleration zone. The increase in water flow velocity can reach 1.2 to 3.5 times the average flow velocity at the conventional inlet, thereby enhancing the convective heat transfer near the outer wall of the heat exchange thick-walled tube 7. Since the pressure end face 20 and the working end face 21 act on different media, the pulsating energy on the hot side is directly transferred to the local flow velocity increase on the cold side through the elastic deformation of the bladder. No additional drive motor or hydraulic actuator is required. Therefore, it can work continuously under the variable operating conditions of the air compressor and reduce additional energy consumption and control complexity.

[0023] Pressure sensors 23 are respectively installed in the intake manifold 16 and the exhaust manifold 18. The pressure sensors 23 are connected to the control system 13 and are used to obtain instantaneous pressure data. Pressure sensors 23 are respectively installed in the intake manifold 16 and the exhaust manifold 18. The pressure sensor 23 in the intake manifold 16 is used to collect instantaneous pressure data before entering the heat exchange thick-walled tube 7, and the pressure sensor 23 in the exhaust manifold 18 is used to collect instantaneous pressure data after the fluid passes through the heat exchange thick-walled tube 7. Both pressure sensors 23 are connected to the control system 13. The pressure sensor 23 can be a piezoresistive, thin-film strain gauge, or quartz piezoelectric dynamic pressure sensor 23. The range is preferably 0MPa to 2.5MPa or 0MPa to 4.0MPa, the dynamic response frequency is preferably not less than 5kHz, and the sampling frequency is preferably 10kHz to 100kHz to ensure that the high-frequency harmonic components in the exhaust pulsation of the air compressor can be captured. The sensor installation location should avoid direct scouring dead corners and weld heat-affected zones. It is preferable to open pressure measurement interfaces on the side walls of the intake manifold 16 and the exhaust manifold 18, and connect them to the sensor through diaphragm sealing joints, thereby reducing the impact of oil deposits and temperature drift on measurement accuracy. The control system 13 receives analog voltage, current signals or digital bus signals output by the pressure sensor 23, and completes filtering, clock synchronization, harmonic extraction and valve position control output. Since the pressure sensor 23 measures instantaneous pressure data rather than average pressure data, the control system 13 can identify the amplitude, phase and frequency changes of the pulsating waveform, and thereby calculate the boundary layer state and damping dissipation level inside the heat exchange thick-walled tube 7. This acquisition method does not require the placement of temperature probes, deposition thickness probes or high-temperature viscosity sensors inside the thick-walled tube, reducing the possibility of sensor failure in high-temperature oily environments, and at the same time providing raw data for impedance mapping control.

[0024] The micro jet oscillator array 8 includes uniformly distributed fluid oscillation chambers 24, wherein the output nozzles 28 of the fluid oscillation chambers 24 are directly opposite the inlet center of the adjacent heat exchange thick-walled tube 7; The micro jet oscillator array 8 consists of multiple evenly distributed fluid oscillation chambers 24. Even distribution means that each oscillation chamber is equidistantly arranged along the circumference of the air inlet confluence area 16 or the planar mounting base, so that the bypass airflow has the same effect on the inlet of each group of heat exchange thick-walled tubes 7 as much as possible. Each fluid oscillation chamber 24 includes an air supply inlet 25, a feedback channel 26, an oscillation main chamber 27, and an output nozzle 28. It uses the fluid wall adhesion effect and feedback loop to form self-excited oscillation, and can output pulsating jets without relying on electromagnetic drive components. The output nozzle 28 is directly opposite the inlet center of the adjacent heat exchange thick-walled tube 7, so that the pulsating jet can enter the inlet region along the axial direction of the heat exchange thick-walled tube 7 and excite the near-wall layer disturbance inside the tube. Taking sixteen heat exchange thick-walled tubes 7 as an example, four fluid oscillation chambers 24 can be set, each fluid oscillation chamber 24 corresponding to four adjacent heat exchange thick-walled tubes 7; the outlet diameter of the nozzle 9 can be 1mm to 4mm, the angle between the spray direction and the axis of the heat exchange thick-walled tube 7 can be 0° to 15°, and the distance between the nozzle 9 and the corresponding thick-walled tube inlet can be 3mm to 30mm; the oscillation frequency of the fluid oscillation chamber 24 can be set in the range of 200Hz to 5000Hz by the chamber size and the air supply pressure. This frequency covers the available high-frequency range in the exhaust pulsation of the air compressor, so that the acoustic flow effect is concentrated on the near-wall oil film and thermal boundary layer; Compared with directly increasing the mainstream flow rate, this structure concentrates the limited bypass high-pressure gas source on the near-wall region of the inlet of the heat exchange thick-walled tube 7. Under the premise of meeting the pressure drop design requirements of the main circuit, it can improve the boundary layer disturbance intensity and reduce the increase in thermal resistance caused by high-viscosity oil film.

[0025] Example 2: Combination Figure 4 As shown, a control method for an air compressor waste heat recovery device includes: S1. Real-time acquisition of instantaneous pressure data at the inlet and outlet of the hot side channel 4; S2. Based on the instantaneous pressure data at the intake end, extract the amplitude of the first high-frequency harmonic component of the intake end pressure signal of the hot side channel 4. S3. Based on the instantaneous pressure data at the outlet, extract the amplitude of the second high-frequency harmonic component of the pressure signal at the outlet of the hot side channel 4. S4. Calculate the difference between the amplitude of the first high-frequency harmonic component and the amplitude of the second high-frequency harmonic component; S5. Divide the difference by the amplitude of the first high-frequency harmonic component to calculate the high-frequency pulse attenuation rate. The control method is based on the mechanical structure of the device. In S1, the control system 13 synchronously reads the instantaneous pressure data output by the pressure sensors 23 at the inlet and outlet ends at a predetermined sampling frequency. The instantaneous pressure data can be a discrete sequence after analog-to-digital conversion of a continuous time series. The sampling duration can be set according to a sliding time window of 0.1s to 2s. In S2, the intake pressure data is de-DC biased and bandpass filtered. The preferred bandpass range is 200Hz to 5000Hz. Then, the amplitude of the first high-frequency harmonic component in the preset frequency band of the intake pressure signal is extracted by fast Fourier transform, discrete Fourier transform or digital phase-locked loop algorithm. The amplitude of the first high-frequency harmonic component represents the high-frequency energy level of the hot side pulsation before entering the heat exchange thick-walled tube 7. In S3, the amplitude of the second high-frequency harmonic component is extracted from the outlet pressure data according to the same time window, the same filtering conditions and the same frequency index to ensure that the comparison before and after has a consistent benchmark. In S4, this difference reflects the amount of amplitude lost by the high-frequency pressure pulsation as it passes through the heat exchange thick-walled tube 7. In S5, the above difference is then divided by the amplitude of the first high-frequency harmonic component to obtain the dimensionless high-frequency pulse attenuation rate; if... Indicates the amplitude of the first high-frequency harmonic component, with Let represent the amplitude of the second high-frequency harmonic component. Then, the high-frequency pulse attenuation rate η can be calculated as follows: in: This represents the high-frequency pulse attenuation rate, a dimensionless percentage. Indicates the amplitude of the first high-frequency harmonic component; Indicates the amplitude of the second high-frequency harmonic component; and Both units are units of pressure and have the same dimensions; to avoid [further issues] If the divisor is too small, causing an abnormality, you can set... The minimum effective value; when When the value is below the minimum effective value, maintain the control cycle of the previous period. Or it may enter the conservative valve position.

[0026] This high-frequency pulse attenuation rate is not a conventional pressure drop coefficient, but rather a characterizing parameter reflecting the dissipation capacity of the near-wall layer within the pipe. When the boundary layer thickens, coking occurs, or oil film adhesion strengthens, the loss during the transmission of high-frequency pressure pulsations increases. Consequently, it increases; when the boundary layer is weakened, The temperature drops. Therefore, changes in the heat transfer state can be inferred using available macroscopic pressure signals without directly measuring the boundary layer thickness. Specifically, since the energy dissipation of high-frequency pressure pulsations propagating in the pipe is positively correlated with the viscosity of the near-wall fluid and the thickness of the boundary layer, when high-viscosity oil film adhesion or coking deposition occurs on the inner wall of the pipe, leading to a thickening of the boundary layer, the acoustic impedance and frictional damping of the pipe wall to high-frequency pulsations increase significantly. Since this increase in damping directly leads to a greater attenuation of pulsating energy between the inlet and outlet, by extracting and calculating the difference ratio of high-frequency harmonic components at the inlet and outlet, the degree of fouling or thickening of the boundary layer inside the tube can be characterized in real time and quantitatively. This calculation logic essentially establishes an impedance mapping calculation model based on macroscopic pressure. Its purpose is to accurately assess the real-time heat transfer resistance state inside the heat exchange thick-walled tube 7 when the thickness of the internal micro boundary layer cannot be directly measured. Specifically, in terms of data flow and algorithm implementation, the control system 13 converts the analog voltage signal input from the pressure sensor 23 into a 16-bit digital signal via an analog-to-digital converter, forming a discrete sequence of length N. A fourth-order Butterworth bandpass filter is used for filtering, and the filtered sequence is then fed into a fast Fourier transform module to extract the amplitude of the target frequency band as... and A2; To further verify the theoretical basis and feasibility of this impedance mapping derivation model, the following quantitative derivation example is provided: Assuming a clean pipe wall condition, the amplitude of the second high-frequency harmonic component is measured at the inlet end. The amplitude was measured at the outlet. At this time, the high-frequency pulse attenuation rate is: When a high-viscosity oil film adheres to the pipe wall, causing boundary layer thickening, the internal frictional damping increases, and the dissipation of pulsating energy intensifies. At this point, the intake end... Still But the air outlet Descending to The new attenuation rate is calculated as follows: Through this clear data flow and calculation rule, the boundary layer thickness change, which is difficult to measure directly, can be characterized as a macroscopic pressure differential attenuation rate without the need for complex internal micro-flow field measurements, thus providing a reliable basis for control decisions.

[0027] The steps following S5 include: S601. Obtain the upper limit of the reference error envelope pre-constructed based on the calibration conditions, and compare the calculated high-frequency pulse attenuation rate with the upper limit of the reference error envelope. S602. If the high-frequency pulse attenuation rate is greater than the upper limit of the reference error envelope, the pneumatic proportional valve 11 is controlled to increase its opening and the bypass airflow pulse width of the driving micro jet oscillator array 8 is increased. S603. The jet generated by the micro jet oscillator array 8 is used to strip the fluid boundary layer inside the heat exchange thick-walled tube 7. S604. If the high-frequency pulse attenuation rate is less than or equal to the upper limit of the reference error envelope, then maintain the current opening of the pneumatic proportional valve 11. After obtaining the high-frequency pulse attenuation rate, the control system 13 executes the threshold comparison and adjustment logic; the upper limit of the preset reference error envelope in S601 is a reference threshold obtained based on the factory calibration or operation calibration of the device. This threshold can be established as a lookup table value under different exhaust pressure, exhaust temperature and cooling water flow conditions, or it can be stored as a set of piecewise functions; the so-called reference error envelope refers to the allowable fluctuation boundary of the high-frequency pulse attenuation rate when the heat exchange state of the device is normal, there is no obvious coking and the bypass excitation energy is within the preset operating range; the upper limit can be set as the reference attenuation rate plus an allowable deviation of 0.02 to 0.15; In S602, when the current high-frequency pulse attenuation rate is greater than the upper limit, it indicates that the damping dissipation of high-frequency pulsation inside the heat exchange thick-walled tube 7 is higher than the normal level. The control system 13 outputs an opening command to the pneumatic proportional valve 11. The valve opening can be increased by proportional increment, integral increment or step increment. At the same time, the bypass airflow pulse width supplied to the micro jet oscillator array 8 is increased. The pulse width here can be characterized by the duty cycle of the valve-controlled air path or the effective continuous air supply duration. Its increase will improve the jet amplitude and near-wall disturbance strength in the oscillation cavity. In S603, after the jet generated by the micro jet oscillator array 8 enters the inlet region of the heat exchange thick-walled tube 7, a periodic velocity gradient and local pressure disturbance are formed in the near-wall layer, which causes the high viscosity oil film attached to the inner wall of the tube to be thinned, the boundary layer thickness is reduced, and the early deposits are inhibited from continuing to adhere. In S604, when the high-frequency pulse attenuation rate is less than or equal to the upper limit value, it indicates that the current damping level is still within the allowable range. The control system 13 maintains the current opening of the pneumatic proportional valve 11 to avoid unnecessarily increasing the bypass air intake. This control logic makes the jet excitation only enhanced when an abnormal increase in impedance is detected, thereby reducing compressed air consumption while maintaining heat exchange performance. The physical meaning of the upper limit value of the reference error envelope in the control system 13 is to characterize the degree of deviation of the current high-frequency pulse attenuation rate from the allowable upper boundary of the normal heat exchange state. It is neither an arbitrary empirical constant nor a single fixed value, but a judgment threshold derived from calibration data. The process for determining this upper limit can be as follows: Step 1, select multiple operating segments when the device is in clean heat exchange thick-walled tube 7, rated or graded stable operating condition, and the micro jet oscillator array 8 is at the reference excitation energy; Step 2, calculate the high-frequency pulse attenuation rate sequence according to S1 to S5 in each operating segment, and remove start-up and shutdown transients, sensor failure points, and obvious outliers; Step 3, group the high-frequency pulse attenuation rate sequence according to three operating condition variables: exhaust pressure, exhaust temperature, and cooling water flow rate, to obtain the reference attenuation rate and its allowable fluctuation band under each operating condition; Step four: Write the upper boundary of each group of allowable fluctuation bands into the memory of the control system 13 to form lookup table data or piecewise function data of the upper limit value of the reference error envelope; when the control system 13 is running, it first reads the operating condition interval to which the real-time exhaust pressure, exhaust temperature and cooling water flow belong, then retrieves the upper limit value from the corresponding interval, and then compares the currently calculated high-frequency pulse attenuation rate with the upper limit value; thus, the input source, generation logic and decision-making role of the upper limit value form a closed loop. The process of increasing the bypass airflow pulse width in S602 can be as follows: After determining that the current high-frequency pulse attenuation rate exceeds the limit, the control system 13 first calculates the over-limit amplitude, that is, the difference between the current high-frequency pulse attenuation rate and the upper limit value; then selects a preset increment level according to the difference, for example, adding a small pulse width when the limit is slightly exceeded, adding a medium pulse width when the limit is moderately exceeded, and adding a large pulse width when the limit is severely exceeded; the corresponding valve control output is applied to the pneumatic proportional valve 11 or its upstream on / off execution unit to increase the effective air supply duration within a unit control cycle; the final output of this process is a new valve position command and a new effective air supply duration command, which together serve as the driving input of the micro jet oscillator array 8; To avoid overshoot, the control system 13 can also set a maximum increment limit per cycle and a number of consecutive limit confirmations. For example, the system will only execute the additional opening after two to five consecutive sliding time windows have been determined to be over the limit, thereby reducing the probability of malfunction caused by occasional noise. In the above determination process and control logic, since the reference attenuation rate and its allowable fluctuation band are affected by the exhaust pressure, exhaust temperature and cooling water flow, a multi-dimensional threshold mapping logic structure is constructed inside the control system 13. The logic structure receives real-time collected exhaust pressure, exhaust temperature and cooling water flow as input parameters, and matches the corresponding upper boundary of the allowable fluctuation band in the pre-stored operating condition database, thereby outputting the dynamic upper limit value under the current operating condition. Due to the introduction of the dynamic matching mechanism, the control system 13 can avoid misjudgment caused by using a single static threshold under changing operating conditions, thereby ensuring that the adjustment command of the jet excitation energy is accurately matched with the current real heat exchange demand. To ensure that the above control logic is fully programmable at the software level, the processing flow of selecting a preset incremental level based on the difference includes clearly defined data flow and decision mapping rules: Let Δη be the difference between the current high-frequency pulse attenuation rate and the upper limit. The control system 13 internally sets three judgment intervals, with the specific decision mapping rules as follows: When 0 < Δη ≤ 5%, it is judged as a slight over-limit, and the control system 13 outputs a command to increase the duty cycle of the bypass airflow pulse width by 5%; when 5% < Δη ≤ 15%, it is judged as a moderate over-limit, and the output command increases the duty cycle by 10%; when Δη > 15%, it is judged as a severe over-limit, and the output command increases the duty cycle by 20%; when Δη ≤ 0, it is judged as no over-limit, and the duty cycle remains unchanged. The mapping logic receives Δη as input, compares it with the decision table, directly outputs the corresponding duty cycle increment and adds it to the current drive command, and sends it to the valve position output module of the pneumatic proportional valve 11. By explaining the execution details and threshold range of the above algorithm in detail, the data flow and decision mapping rules determined inside the system are disclosed, enabling the system to automatically and accurately output the excitation energy that matches the current heat exchange anomaly level.

[0028] Following the steps in S603 are: S701. Obtain the median of the reference error envelope pre-constructed based on the calibration conditions, and continuously calculate to obtain the new high-frequency pulse attenuation rate; S702. Compare the new high-frequency pulse attenuation rate with the median of the reference error envelope; S703. If the new high-frequency pulse attenuation rate is less than the median of the reference error envelope, control the pneumatic proportional valve 11 to reduce the opening and reduce the excitation energy of the micro jet oscillator array 8. S704. If the new high-frequency pulse attenuation rate is greater than or equal to the median of the reference error envelope, then maintain the increased opening state of the pneumatic proportional valve 11. To avoid frequent adjustments of the pneumatic proportional valve 11 near the threshold, the control method continues to introduce a fallback criterion after executing S603; the median of the preset reference error envelope in S701 corresponds to the center reference value of the normal operating range, and its value is lower than the upper limit value. It can be understood as the judgment benchmark when the system recovers to a lower damping state. The median value can be obtained through calibration, for example, the average high-frequency pulse attenuation rate during normal and stable operation under a certain operating condition is used as the median value; the control system 13 continuously calculates the new high-frequency pulse attenuation rate in the same way, with the same time window and the same frequency band; In S702, the new high-frequency pulse attenuation rate is compared with the median to determine whether the boundary layer reduction has reached the predetermined level. In S703, when the new high-frequency pulse attenuation rate is less than the median, it indicates that the high-frequency dissipation in the heat exchange thick-walled tube 7 has fallen back to a region below the median. Based on this, the control system 13 controls the pneumatic proportional valve 11 to reduce its opening and simultaneously reduces the excitation energy of the micro jet oscillator array 8. The reduction in excitation energy can be manifested as a reduction in bypass air volume, a decrease in supply air pressure, or a shortening of the effective pulse width. The valve position reduction can be 2% to 20% of the current opening, or it can be gradually reduced according to the slope limit to maintain stable regulation. In S704, when the new high-frequency pulse attenuation rate is still greater than or equal to the median value, it indicates that the damping has not yet returned to the target range. The control system 13 maintains the previous state of increasing the opening until the fall-off condition is met again. By setting the upper limit and the median value at the same time, the control system 13 forms an adjustment mechanism with a hysteresis range, which can reduce valve shaking and ineffective adjustment, improve the utilization rate of the bypass air source, and reduce the cumulative load of the heat exchange thick-walled tube 7 subjected to excessive acoustic flow excitation for a long time. The role of the median of the reference error envelope in the control logic is to serve as the judgment benchmark for the exit condition of the increased state. Its physical meaning is the reference attenuation rate corresponding to the recovery of the high-frequency damping inside the heat exchange thick-walled tube 7 to the normal central region under the current operating conditions. The preferred method for determining the median is to use the same operating condition grouping basis as the upper limit value. That is, within the same exhaust pressure, exhaust temperature and cooling water flow range, the central representative value is obtained from the high-frequency pulse attenuation rate samples obtained under clean and stable heat exchange conditions. The central representative value can be the sample mean, median value or the average value after removing outliers, so as to reduce the impact of occasional pulsation disturbances. When the control system 13 is running, it first retrieves the median value of the same group as the upper limit value according to the current operating condition index, and then compares the new high-frequency pulse attenuation rate with the median value, so as to ensure that the median value and the upper limit value are consistent in origin and logic. The processing flow from S701 to S704 can be broken down as follows: Step 1: After the control system 13 performs the additional opening, it does not change the pressure sampling path and continues to calculate the new high-frequency pulse attenuation rate according to the same sensor input, the same time window length, and the same frequency band range as mentioned above; Step 2: The control system 13 sequentially compares the new attenuation rates obtained from multiple consecutive control cycles to determine the recovery trend, rather than immediately reverting based solely on a single sampling result; Step 3: When the new high-frequency pulse attenuation rates are all less than the median value for a predetermined number of consecutive cycles, a reverting command to reduce the valve position and reduce the excitation energy is output; Step 4: If the reverting conditions are not met consecutively, the current additional opening state remains unchanged. The aforementioned number of consecutive predetermined times can be 2 to 6 times, with the aim of distinguishing short-term fluctuations from true recovery; thus, the median is not only interpreted as a numerical threshold, but its source, comparison method, and triggering relationship with the valve position retraction action are also clearly disclosed. To ensure the programmability of the valve position reduction action and the clarity of data flow, the step of controlling the pneumatic proportional valve 11 to reduce its opening adopts a step-back algorithm based on the deviation ratio. Specifically, let the absolute value of the difference between the current new high-frequency pulse attenuation rate and the median value be Δη_return. The control system 13 multiplies Δη_return by a preset attenuation gain coefficient K to calculate the valve position return percentage. Here, the attenuation gain coefficient K is a preset constant, and its value ranges from 0.1 to 0.5. Subtract this return percentage from the current valve opening to generate a new target valve position command. To prevent system oscillation caused by excessively rapid backoff, the control system 13 also sets an upper limit on the single backoff step size in the software logic. The above calculation rules clarify the complete data processing process from inputting a new high-frequency pulse attenuation rate, to comparing the median value, and then to outputting a specific command to reduce the opening degree. This transforms the abstract control process of reducing excitation energy into executable code logic, ensuring a smooth transition of the system when it returns to normal heat exchange state.

[0029] Step S1 includes the following: S01. Obtain pressure pulsation data in the hot side channel 4. When the pressure pulsation data is at a peak, the antagonistic corrugated prestressed energy storage chamber 12 is compressed and absorbs the peak kinetic energy of the pulsation. S02, the working end face 21 of the antagonistic corrugated prestressed energy storage chamber 12 is squeezed into the cold side channel 5, which forces the incoming cooling water flow rate to increase dramatically and form a scouring jet on the outer wall of the heat exchange thick-walled tube 7. Before performing pressure data acquisition and attenuation rate calculation, the device body has already completed the transfer of hot-side pulsating energy through pure mechanical response; in S01, the pressure pulsating data in the hot-side channel 4 can be directly acquired by the pressure sensor 23 set in the inlet confluence area 16, or the control system 13 can identify local peaks in the existing instantaneous pressure sequence. When the pressure pulsating data characterization is at the peak, the antagonistic corrugated prestressed energy storage chamber 12 is subjected to an external load higher than the pre-charge equilibrium pressure, and the stainless steel elastic bladder 19 is compressed along the axial direction, absorbing part of the kinetic energy and pressure potential energy corresponding to the peak, thereby reducing the impact intensity directly transmitted to the inlet of the heat exchange thick-walled tube 7; In S02, as the capsule is compressed, its working end face 21 displaces into the cold side channel 5. The displacement can be 0.2mm to 5mm. This displacement reduces the local flow area of ​​the cooling water inlet, forcing the cooling water passing through this area to accelerate instantaneously. When the cooling water velocity increases, a local scouring jet is formed near the outer wall of the heat exchange thick-walled tube 7, reducing the thickness of the liquid film on the outer wall and increasing the convective heat transfer coefficient. After the pressure pulsation returns from its peak, the capsule returns to its original shape under the action of the internal inert gas pressure and the metal elastic restoring force. The cross-sectional area of ​​the cooling water inlet increases, and the device re-enters the next pulsation response. The mechanical process works in conjunction with the electronic regulation process in the control system 13. The mechanical process is responsible for absorbing the peak value of the pulsation and enhancing the local heat transfer on the cold side within the transient time scale of the pulsation. The control process is responsible for adjusting the excitation energy of the micro jet oscillator array 8 according to the high-frequency pulse attenuation rate within the time scale of the set sampling and control cycle. The two work together to convert a part of the destructive pulsation on the hot side into a driving force for enhanced heat transfer on the cold side, and to provide stable pulsation frequency band conditions for impedance mapping calculation based on instantaneous pressure data. In S01, the pressure pulsation data is characterized at the peak. It is preferred to use explicit identification logic rather than general judgment. Its input source is the instantaneous pressure sequence collected by the pressure sensor 23 in the intake manifold 16. The control system 13 can first process the instantaneous pressure sequence to remove the DC component, so as to obtain a pressure waveform that only reflects the pulsation component. Then, it can identify the local maximum point within the sliding time window. When the instantaneous pressure corresponding to a local maximum point is higher than the average value of the pulsation within the same time window and the subsequent sampling points show a downward trend, it is determined that a peak has arrived. If the device adopts a pure mechanical priority response mode, the above peak identification is mainly used for recording and analysis. The antagonistic corrugated prestressed energy storage chamber 12 can be automatically compressed when the pressure exceeds its pre-charge balance pressure, without waiting for the controller to issue an execution command. S02 forces a dramatic increase in the velocity of the incoming cooling water, forming a scouring jet on the outer wall of the heat exchange thick-walled tube 7. The formation process can be broken down into the following steps: Step 1: The hot-side crest compresses the stainless steel elastic bladder 19, and the working end face 21 of the bladder propels it toward the cold-side inlet; Step 2: The effective flow cross-sectional area of ​​the cooling water inlet decreases locally, while the total flow rate of the main cooling water circuit remains continuous for a short period of time; Step 3: The cooling water is thus locally accelerated in the region adjacent to the working end face 21 of the bladder, forming a high-velocity water flow band that develops along the outer wall of the heat exchange thick-walled tube 7. Step four: The high-velocity water flow has a scouring effect on the liquid film at the boundary of the outer wall of the heat exchange thick-walled tube 7, which reduces the local heat transfer resistance. The output of this process is not a new control command, but a local increase in flow velocity at the cold side inlet and enhanced heat transfer due to scouring of the outer wall. This mechanical response result, together with the pressure decay rate calculation, constitutes the state basis of the entire system. Because the antagonistic corrugated prestressed energy storage chamber 12 can undergo instantaneous axial compression when the pressure wave peak on the hot side arrives, the high-energy pulse impact on the hot side is converted into the potential energy of the inert gas inside the chamber and the deformation energy of the metal, thereby effectively weakening the destructive shock wave that directly acts on the inlet of the heat exchange thick-walled tube 7; at the same time, because the working end face 21 of the chamber simultaneously squeezes the cooling water inlet on the cold side, the local flow cross-sectional area on the cold side is drastically reduced, forcing the cooling water flow rate to increase and forming a scouring jet on the outer wall of the heat exchange thick-walled tube 7; Because the above mechanical response process realizes the direct physical transfer of pulsating energy on the hot side to enhanced kinetic energy for heat exchange on the cold side, it not only eliminates the risk of fatigue damage to the pipe structure caused by high-frequency strong noise, but also provides reliable boundary conditions for the subsequent extraction of a stable inlet pressure signal for impedance mapping calculation.

[0030] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. An air compressor waste heat recovery device, characterized by, include: A heat exchange housing (1) is connected to a cooling water outlet pipe (2). The interior of the heat exchange housing (1) is divided into a hot side channel (4) and a cold side channel (5) by a fixed partition (3). The air inlet of the heat exchange housing (1) is connected to the air compressor exhaust pipe (6). Heat exchange thick-walled tubes (7) are arranged in parallel inside the hot side channel (4). The two ends of the heat exchange thick-walled tubes (7) are respectively welded to the fixed partition (3). The outer wall of the heat exchange thick-walled tubes (7) contacts the cooling water introduced into the cold side channel (5). A micro jet oscillator array (8) is fixedly connected to the heat exchange housing (1) and leads to a nozzle (9). The nozzle (9) is directly opposite the inner hole of the heat exchange thick-walled tube (7). The micro jet oscillator array (8) is connected to a high-pressure exhaust bypass pipe (10). A pneumatic proportional valve (11) is disposed between the high-pressure exhaust bypass pipe (10) and the micro jet oscillator array (8); Antagonistic corrugated prestressed energy storage chamber (12) is disposed between the fixed partition (3) and the side wall of the heat exchange shell (1). The hot side end face of the antagonistic corrugated prestressed energy storage chamber (12) is exposed to the air inlet end of the hot side channel (4). The cold side end face of the antagonistic corrugated prestressed energy storage chamber (12) extends to the cooling water inlet of the cold side channel (5). The control system (13) controls the pneumatic proportional valve (11) based on instantaneous pressure data.

2. The waste heat recovery device for an air compressor according to claim 1, characterized by, The heat exchange housing (1) is divided into an air intake confluence area (16), a heat exchange core area (17) and an exhaust confluence area (18) by a first fixed partition (14) and a second fixed partition (15). The air intake confluence area (16) and the exhaust confluence area (18) constitute the hot side channel (4), and the heat exchange core area (17) constitutes the cold side channel (5).

3. The waste heat recovery device for an air compressor according to claim 2, characterized in that, The main body of the antagonistic corrugated prestressed energy storage chamber (12) is a corrugated stainless steel elastic bladder (19), wherein the interior of the stainless steel elastic bladder (19) is filled with inert gas.

4. The waste heat recovery device for an air compressor according to claim 3, characterized in that, The pressure end face (20) of the stainless steel elastic bladder (19) faces the incoming flow direction of the air intake confluence area (16), and the working end face (21) of the stainless steel elastic bladder (19) passes through the reserved hole (22) on the first fixed partition (14) and extends into the cooling water inlet of the cold side channel (5).

5. The waste heat recovery device for an air compressor according to claim 2, characterized in that, Pressure sensors (23) are respectively installed in the intake manifold (16) and the exhaust manifold (18). The pressure sensors (23) are connected to the control system (13) and are used to obtain instantaneous pressure data.

6. The waste heat recovery device for an air compressor according to claim 1, characterized in that, The micro jet oscillator array (8) includes uniformly distributed fluid oscillation cavities (24), wherein the output nozzles (28) of the fluid oscillation cavities (24) are directly opposite the inlet center of the adjacent heat exchange thick-walled tube (7).

7. A control method for an air compressor waste heat recovery device, applied to the air compressor waste heat recovery device as described in claim 1, characterized in that, include: S1. Real-time acquisition of instantaneous pressure data at the inlet and outlet of the hot side channel (4); S2. Based on the instantaneous pressure data of the intake end, extract the amplitude of the first high-frequency harmonic component of the intake end pressure signal of the hot side channel (4); S3. Based on the instantaneous pressure data at the outlet, extract the amplitude of the second high-frequency harmonic component of the pressure signal at the outlet of the hot side channel (4). S4. Calculate the difference between the amplitude of the first high-frequency harmonic component and the amplitude of the second high-frequency harmonic component; S5. Divide the difference by the amplitude of the first high-frequency harmonic component to calculate the high-frequency pulse attenuation rate.

8. The control method according to claim 7, characterized in that, Step S5 is followed by: S601, obtaining the upper limit value of the reference error envelope pre-constructed based on the calibration conditions, and comparing the calculated high-frequency pulse attenuation rate with the upper limit value of the reference error envelope; S602. If the high-frequency pulse attenuation rate is greater than the upper limit of the reference error envelope, then control the pneumatic proportional valve (11) to increase its opening and increase the bypass airflow pulse width that drives the micro jet oscillator array (8). S603. The jet generated by the micro jet oscillator array (8) strips away the fluid boundary layer inside the heat exchange thick-walled tube (7); S604. If the high-frequency pulse attenuation rate is less than or equal to the upper limit of the reference error envelope, then maintain the current opening of the pneumatic proportional valve (11).

9. The control method according to claim 8, characterized in that, The step S603 is followed by: S701, obtaining the median of the reference error envelope pre-constructed based on the calibration conditions, and continuously calculating to obtain a new high-frequency pulse attenuation rate; S702. Compare the new high-frequency pulse attenuation rate with the median of the reference error envelope; S703. If the new high-frequency pulse attenuation rate is less than the median of the reference error envelope, then control the pneumatic proportional valve (11) to reduce its opening and reduce the excitation energy of the micro jet oscillator array (8). S704. If the new high-frequency pulse attenuation rate is greater than or equal to the median of the reference error envelope, then the pneumatic proportional valve (11) is maintained in an increased opening state.

10. The control method according to claim 7, characterized in that, Before step S1, the following steps are included: S01, obtaining pressure pulsation data in the hot side channel (4), when the pressure pulsation data indicates that it is at a peak, the antagonistic corrugated prestressed energy storage chamber (12) is compressed to absorb the peak kinetic energy of the pulsation. S02, the working end face (21) of the antagonistic corrugated prestressed energy storage chamber (12) is squeezed into the interior of the cold side channel (5), which forces the incoming cooling water flow rate to increase dramatically and form a scouring jet on the outer wall of the heat exchange thick-walled tube (7).

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