Maximum Sound Pressure Level Research Articles

Generation of broadband airborne ultrasound using an Harmonic Acoustic Pneumatic Source

This paper presents a new type of airborne transducer for generating broadband ultrasound with a high Sound Pressure Level (SPL). The concept is based on the Harmonic Acoustic Pneumatic Source (HAPS) that uses pressurized air in conjunction with a flow chopper made up of a rotating cage with slots connected to a specific exhaust. The fundamental frequency depends on the number of slots and the rotation speed of the cage. An analytical model of the HAPS coupled with a numerical model of the exhaust is used to predict the radiated acoustic pressure and to estimate the influence of dimensional parameters on pressure level generated by the source. Experiments are conducted with two cages: one with one slot in order to generate pulses periodically and one with 122 slots to generate periodic sound. The level of sound pressure is measured as a function of distance (0.004 to 0.5 m), the cage rotation (up to 11 krpm) and directivity (0 to 90°). For the fundamental frequency at 22 kHz, the maximum SPL of 150 dB (632 Pa rms) is /measured at 0.004 m, and decreases to 122 dB (35 Pa rms) at 0.5 m. At 0.5 m, the second and third harmonics can generate a SPL equal or greater than 115 dB above 22 kHz and up to 66 kHz. Discrepancies between the experiments results and numerical model are observed in terms of SPL, directivity and in-axis pressure.

Weak hammering sounds are associated with postoperative subsidence in cementless total hip arthroplasty.

The aim of this study was to investigate the relationship between the hammering sound level and the presence of postoperative subsidence. The last five hammering sounds during the final-size broaching procedure and during the real stem insertion were recorded and analysed in 95 patients who were operated on by one of seven surgeons using two implants (Trident cup, Accolade II, Stryker; G7 cup, Taperloc Complete Microplasty Stem, Zimmer Biomet). The maximum peak was semi-automatically identified and analysed to determine the maximum C-weighted sound pressure level (LCpeak) of each of the five hammering sounds and the equivalent continuous A-weighted sound pressure (LAeq) of the entire five-sound hammering procedure. Among the 95 hips, 25 (26.3%) had ≥ 3mm of postoperative subsidence. Therefore, 125 of 475 hammering sounds (LCpeak) and 25 of 95 hammering procedures (LAeq) in both the broaching procedure and stem insertion procedure were associated with postoperative subsidence. The hammering sound level in both the broaching and stem insertion procedures were significantly weaker in patients with postoperative subsidence than in those without subsidence. Among the seven surgeons, there was intra-surgeon and inter-surgeon heterogeneity with large variance regarding the sound levels. With univariate and multivariate analyses, the hammering sound level was independently associated with postoperative subsidence in the two models. A weak hammering sound level was associated with postoperative subsidence in THA with a cementless stem. An objective evaluation of the hammering procedure might be useful to decrease the incidence of postoperative subsidence.

Increasing the efficiency of coagulation in resonant gaps due to acoustic flow formation

Relevance. The urgent need to eliminate environmental pollution from industrial emissions of various solid particles. At the same time, maximum attention is paid to cleaning exhaust gases from particles of 2.5 microns in size or less. One of the most promising ways to increase the efficiency of existing gas purification equipment in capturing such particles is their coagulation by exposing the gas flow to high-intensity acoustic vibrations of ultrasonic frequency. However, at low concentrations, even at the maximum permissible sound pressure level, the coagulation efficiency of particles smaller than 2.5 microns is insufficient to increase the recovery rate of gas cleaning equipment. Therefore, there is an urgent need to find new ways to further improve the efficiency of ultrasonic coagulation of particles smaller than 2.5 μm. Aim. To determine the conditions for the formation of vortex flows in ultrasonic fields with the maximum ultrasonic influence in terms of sound pressure level. Conducting comparative studies of the coagulation of particles with a size of 2.5 microns with and without vortex flows. This will make it possible to determine the real values of increasing the efficiency of ultrasonic coagulation during turbulization of a gas-dispersed flow by acoustic flows in comparison with coagulation in a uniform ultrasonic field and without it. Objects. Coagulation of particles under the influence of homogeneous and inhomogeneous ultrasonic fields. Methods. Computer modeling of the formed ultrasonic field by the finite element method using harmonic acoustic analysis. The paper considers the experimental method for studying the process of combining particles under the influence of ultrasonic vibrations. To determine the characteristics of an aerosol during experimental studies, a TIPAS-1 meter based on the small-angle scattering method and the spectral transparency method was used. Results. The paper introduces the results of studies of coagulation of particles with a size of 2.5 microns or less in an ultrasonic field formed in resonant gaps by oscillating disk emitters. The authors proposed to increase the efficiency of coagulation in resonant gaps through the use of ultrasonic disk emitters capable of forming alternating zones of maximum and minimum amplitude oscillations in the resonant gaps. The creation of such zones ensured the formation of vortex-type acoustic flows capable of moving particles within the nodal regions of a standing wave and between them. The involvement of small particles in the formed flows made it possible to increase the probability of their collision. It was established that more effective ultrasonic coagulation provides an increase in the degree of inertial capture for particles of 2.5 microns in size by 6% – from 89 to 95%, for particles of 1.5 microns in size by 7% – from 85 to 92%, and for particles of 0.5 microns by 9% – from 76 to 85%.

Exploring cavitation dynamics and noise reduction in hydraulic machinery with bionic leading edge impeller

Cavitation and induced noise are common issues in the operation of mixed-flow pumps, affecting their stability. Studying these phenomena is of both academic and engineering interest. Previous research has mainly focused on modifying the impeller blade profile or optimizing the pump structure to reduce cavitation and noise. In this paper, we apply a bionic design to the mixed-flow pump impeller by mimicking the natural shape of a humpback whale's pectoral fin on the leading edge of the blade. We compare the cavitation suppression and noise reduction effects of this design with those of a conventional mixed-flow pump. Unsteady flow calculations for the original pump at different flow rates revealed that at its rated speed, increasing flow rates led to lower pressure in the low-pressure region on the suction surface of the impeller, expanding the cavitation-prone area. By applying the bionic design, we studied the unsteady cavitation flow and its induced noise. Results showed that the impeller and guide vane experienced larger pressure pulsations at the rotation frequency and its multiples. The bionic modification increased the cavitation initiation speed and reduced the cavity volume within the runner. With an NPSH (net positive suction head) of 6.76, the void volume in the bionic pump was only 79% of that in the original pump, and the head increased by 16%. Additionally, the bionic design reduced the maximum far-field sound pressure level by 12.5%, achieving significant noise reduction. This study demonstrates that the bionic design effectively controls dynamic flow separation, reduces flow-induced noise, and enhances the mixed-flow pump's performance. These findings have important theoretical and practical implications for optimizing mixed-flow pump design, improving energy efficiency, and reducing noise.

THD improvement of piezoelectric MEMS speakers by dual cantilever units with well-designed resonant frequencies

In this study, a piezoelectric MEMS (Micro-Electro-Mechanical-System) speaker with thoughtfully selected resonant frequencies of dual cantilever units is designed and implemented. Based on the lead zirconium titanate (PZT) thin film with superior piezoelectric coefficient, the cantilever diaphragm is designed through the modal analysis. In the 1.5 mm by 1.5 mm cantilever array, a high-frequency actuation unit with resonance of 13.1 kHz and a low-frequency actuation unit with resonance of 6.35 kHz constitute the proposed piezoelectric MEMS speaker. The boost of sound pressure level (SPL) due to the resonant mode of low-frequency actuation unit reduces the total harmonic distortion (THD) around the subharmonic frequency of high-frequency actuation unit. Meanwhile, the asymmetric triangle diaphragm reduces the maximum stress in the structure when operating at the resonant frequency, thereby mitigating the THD spikes resulting from the nonlinear structural behavior. In pressure-field measurements, the proposed design can reach SPL ≥ 70.0 dB from 2.7 kHz to 15.0 kHz with only 0.179 Vrms input. At the same time, THD remains below 3.0 % from 3.2 kHz to 20 kHz. The outstanding performance under larger input signal and bias voltage is also verified. Actuated by 0.354 Vrms and 2 VDC bias, the maximum SPL achieves 111.9 dB and the SPL is higher than 80.0 dB from 3.3 kHz to 14.1 kHz. Furthermore, THD is lower than 3.0 % from 1.0 kHz to 8.9 kHz. A promising solution of piezoelectric MEMS speaker for in-ear applications is demonstrated in this study.

Perceptual Evaluation of Sound Exposure Level in Annoyance Ratings to Helicopter Noise

A psychoacoustic test was performed to assess the effectiveness of sound exposure level (SEL) for indicating changes in annoyance to helicopter noise. SEL was evaluated for flyover auralizations of optimized rotor designs and for flyover recordings of different helicopters and maneuvers. The test used paired comparisons of flyovers within 10 dB of the maximum A‐weighted sound pressure level. For stimuli of equal SEL, annoyance responses showed whether or not SEL is a good indicator of annoyance. While this work does not seek to determine specific attributes contributing to annoyance that are not included in SEL, the magnitude of this offset is of primary interest. Specifically, annoyance responses to relative differences in SEL allowed the calculation of an equal annoyance point. Reductions in SEL lead to reductions in annoyance as expected, but for certain cases, SEL can fail to capture perceptually significant features such as audible differences due to changes in tail rotor design or unsteadiness in the sound of the helicopter.

Structural Design and Optimization of Low-Frequency High-Power Electromagnetic Transducer

Crucial equipment for marine engineering and research, high-power ultra-low frequency sound sources have become necessary with the rapid development of seabed resource exploration, marine environment monitoring, underwater remote target detection, and communication technology. The current ultra-low frequency sound source cannot meet the requirements of practical applications. In this paper, both the finite element method and equivalent circuit method are used to improve the electromagnetic acoustic transducer, focusing on solving the structural design of the functional parts of the transducer, as well as the mechanical, electrical, magnetic parametrization of the transducer and other key technologies. The structural parameters and material parameters in the transducer that affect the final performance response are obtained through the optimization of the genetic algorithm. The results show that the electromagnetic acoustic transducer studied in this paper can emit low-frequency sound waves below 50~Hz, and the maximum sound pressure level reaches 138~dB, which meets the requirements of general low-frequency high-power acoustic wave transducers in practical work.

Acoustical analysis and optimization design of the hair dryers

Abstract The sound qualities and wind speeds of the four commercial hair dryers (Panasonic, Confu, Flyco, and Philips) were investigated through experimental methods in the present study. The sound qualities included loudness, sharpness, roughness, and fluctuation strength. The experimental results showed that the maximum sound pressure level (SPL) of all hair dryers occurred at about 200 Hz except Flyco hair dryer, which occurred at about 400 Hz. The highest loudness and highest sharpness were found when the hair dryers were set to hot mode and cold mode, respectively. No consistent relationship was found between the effect of room space and SPLs of the hair dryers. The Box–Behnken design method was used to design 13 pieces of oval and rectangular nozzles, and their sound levels and wind speeds were measured. Thereafter, these experimental results were used to derive correlation coefficients between the hair dryer nozzle area, aspect ratio, nozzle length, loudness, and wind speed using the Anova analysis method. Finally, an oval nozzle and a rectangular nozzle with an area of 0.0005 m 2 {}^{2} , an aspect ratio of 1, and nozzle lengths of 0.052 and 0.055 m, respectively, were designed and were tested. These nozzles managed to reduce the sound loudness by 15 and 9.6%, respectively, while maintaining the same level of wind speed.

Estimation of the effect of thin-plated surface on a three-staged looped thermoacoustic engine for low-grade heat recovery

This paper introduces two novel structures of looped thermoacoustic engines designed for outdoor low-frequency sound sources. The system consists of three thermoacoustic engines in a loop and a stub for sound radiating, which is characterized by reliability, high efficiency, and compactness. Two thin plates are used to prevent the Gedeon flow, facilitate sound propagation, and adjust the acoustic field. The system with a straight stub achieved a maximum Sound Pressure Level of 126.09 dB at 1 m away, surpassing highest reported records by 25.96 %. The system also achieves a high output efficiency of 3.86 %. The system with tapered stub and a 0.1 mm silicone plate, achieved an SPL of 120.76 dB at 1 m. To maintain the predetermined acoustic field, it is important to consider a thin plate with small Young's modulus and thickness. The effect on the acoustic field must be considered when the thickness exceeds 0.8 mm. The addition of the 0.28 mm thin plate in system with tapered stub resulted in a 7.8 W increase in acoustic power compared to that of system without the thin plate.

Noise Analysis and Optimization Design of an Electric–Mechanical–Hydraulic Power Coupler for the Vehicle

This article proposes a new electric–mechanical–hydraulic power coupler (EMHPC). The EMHPC is integrated by a swash plate axial piston pump and permanent magnet synchronous motor, which can realize the conversion of electric, mechanical, and hydraulic energy. To analyze the noise characteristics of the EMHPC, the mathematical models of fluid noise and electromagnetic noise are established, respectively. An optimization model is built based on Isight, and the multi‐island genetic algorithm is used to optimize the triangular groove structure. The optimization results show that the sound pressure level of sound field monitoring points decreases at different frequencies, and the vibration displacement of the cylinder block decreases. The maximum sound pressure level of the directivity curve of the radiated sound field decreases by 9 dB. For the electrodynamic structure optimization of the EMHPC, this article establishes a combination approximation model with higher accuracy. The structure of the stator and rotor is optimized based on the combined approximate model. The optimization results show that the sinusoidal property of the radial air‐gap magnetic density curve is better after optimization, and the harmonic amplitude of the radial electromagnetic force decreases. The maximum sound pressure level in the air domain of the external sound field is reduced from 69 to 60 dB. Moreover, the superposition analysis of fluid noise and electromagnetic noise is carried out, and the main noise sources of the EMHPC in different working modes are determined.

Numerical Investigation on the Aerodynamic and Aeroacoustic Characteristics in New Energy Vehicle Cooling Fan with Shroud

The cooling fan is one of the important noise sources for new energy vehicles, and the research on its aerodynamic and aeroacoustic characteristics is of great help to improve the noise, vibration and harshness performance of new energy vehicles. However, most of these studies focus on the impeller, and little consideration has been given to the study of the shroud. Based on the coupling calculation method of large eddy simulation and the Ffowcs-Williams and Hawkings acoustics model, the aerodynamic and aeroacoustic characteristics in a cooling fan with the shroud are investigated at flow rates from 0.623 kg/s to 1.019 kg/s (where 0.865 kg/s is the flow rate corresponding to the best efficiency point). The accuracy of numerical simulation results is verified by the grid independence verification and the comparison of experimental data. Research shows that several large-scale vortex structures are observed in the clearance between the impeller and the shroud. The maximum peak-to-peak values of pressure fluctuation at different flow rates occur in the intermediate section or outlet section of the shroud. Although the shroud contributes relatively less to the far field noise, its different distribution may change the position of the maximum sound pressure level. The dominant frequency of pressure fluctuation equals the blade passage frequency (BPF) and the maximum SPL is around the BPF, both of which are independent of flow rates. The maximum SPL and the amplitude of the dominant frequency decrease as the flow rate increases.

Development and Application of Open Rotor Discrete Noise Prediction Program Using Time-Domain Methods

The aerodynamic noise of an open rotor is one of the critical challenges that must be considered in its design and application. FODNOPP, a program specifically programmed to predict the aerodynamic discrete noise of single- and counter-rotating open rotors (such as propellers, propfans, and rotorcraft rotors) at subsonic, transonic, and supersonic helical blade tip speeds, has recently been developed by the first author. This program is composed of four prediction codes, namely code a1, code a2, code b, and code c, each based on Farassat-derived formulations Formu 1-RTE, Formu 1A, Formu 1-Sph, and Formu 3, providing time-domain solutions to the Ffowcs Williams–Hawkings equation. Four verification examples for both propeller low-speed flight noise and counter-rotating propfan take-off noise are presented, along with an application case for transonic helical tip speed counter-rotating propfan cruise noise. The results demonstrate the accuracy of FODNOPP in calculating the noise for these verification cases. And in the counter-rotating propfan cruise noise case, the maximum harmonic sound pressure level of the rear propfan is 5.5 dB higher than that of the front propfan. FODNOPP can be referred to as a comprehensive design tool, and it offers valuable guidance for engineering design focused on rotor-related noise reduction.

Bioacoustics of Trogoderma granarium Everts (Coleoptera: Dermestidae)

Trogoderma granarium Everts (Coleoptera: Dermestidae) is one of the major destructive pests of grain products in hot and dry parts of the world. No information has been made available on the bioacoustic signals (BASs) of T. granarium. In this paper, the bioacoustic features of this insect have measured from larvae and adult males and females. No anechoic chamber was used in this study. The extracted features were compared to evaluate the ability of the acoustic method to determine larva or adult as well as their sex. Adult males and females and larvae T. granarium produced BASs with a length of 2–11, 2–52, and 2–30 ms with a maximum sound pressure level of 3, 36, and 17 dB, respectively. At least 60 % of all BASs were in the ranges of 2–12 impulses in larva and adult stages. The sum of the total BASs was different in larvae and adult stages. Adult males had the least number of BASs compared to adult females and larvae. Detection of the growth stage and determination of the sex of the adult T. granarium by acoustic method in the time domain depends on the feature extracted from BASs and number of their impulses. Furthermore, in the frequency domain, the most dominant frequency bands were in the range of 1–8 kHz. In this band, the most dominant frequency band was 3.5–4.5 and 1–1.7 kHz for adult males and larvae, respectively. The most dominant bands of 1–3 and 4–5 kHz were observed for adult females.

Research on the Relationship between Vibration Noise and Magnetic Saturation of Magnetic Saturated Controllable Reactor Based on COMSOL

This article is based on a 2.2 kVar small magnetically saturated controllable reactor (MSCR) prototype and builds a three-dimensional three-field coupling model of its electromagnetic structure acoustics in the finite element simulation software COMSOL. The time-domain sound field distribution of MSCR under electromagnetic force and magnetostrictive effect is obtained through simulation, and DC bias is linearly added. The trend of changes in magnetic saturation and MSCR maximum sound pressure level are obtained, and finally, the relationship curve between MSCR maximum sound pressure level and its magnetic saturation is analyzed, which is similar to the magnetization curve. Taking the half-load working state as the knee point, this study provides a research idea for the design and monitoring of reactors based on the relationship between MSCR acoustics and the working state.

Study of noise and structural characteristics of twin-screw air compressor based on multi-physical field coupling

For the problems of high noise and low efficiency of twin-screw air compressor, the mutual coupling effect of noise and structure for the twin-screw air compressor is studied by using acoustic-solid coupling technology. The simulation model of acoustic-structural coupling of twin-screw air compressor is established. Combining acoustic wave theory calculation with structural characteristics, the sound pressure level distribution and structural deformation law of different tangent planes of the shell at different frequencies under external excitation are studied. The results show that when the frequency is different, the more intensive the acceleration distribution on the shell surface is, the greater the sound pressure level is. At the same frequency, as the incident pressure wave increases, the deformation on the shell also increases, and the maximum shell deformation and the maximum sound pressure level both appear around 2000 Hz. As the frequency increases, the acceleration distribution on the surface of the shell becomes more denser and the sound pressure level becomes larger.

Effects of blade tip thicknesses on hydrodynamic and noise performance of ducted propellers

Propeller noise plays an important role in underwater radiated noise. The radiated noise of a ducted propeller is closely related to the vorticity intensity in the gap between the blade tip and the inner wall surface of the duct. To investigate the influence of blade tip thickening on the hydrodynamic and noise performance of ducted propellers, six different models of ducted propellers with varying blade tip thicknesses are presented. The Reynolds-averaged Navier–Stokes (RANS) method is used to simulate the flow around the ducted propellers, and a combination of Detached Eddy Simulation (DES) and acoustic boundary element method (BEM) is employed to predict the noise. The results show that thickening the blade tips leads to a 4.15% efficiency loss at J = 0.6, but improves efficiency by 17.61% at J = 0.8. As the blade tip thickness increases, the length of the blade tip vortex gradually decreases, and the turbulent kinetic energy (TKE) in the chordwise middle region of the blade tip decreases. Additionally, the peak values of thrust and torque fluctuations of the blades primarily occur at the blade passing frequency (BPF) and its harmonics, with the minimum amplitudes of the BPF at the maximum blade tip thickness. Thickening the blade tips results in a maximum overall sound pressure level reduction of 0.50 dB for the ducted propeller, with a maximum sound pressure level (SPL) reduction of 4.24 dB at certain dominant frequencies.

Effects of Aircraft Noise on Sleep: Federal Aviation Administration National Sleep Study Protocol.

Aircraft noise can disrupt sleep and impair recuperation. The last U.S. investigation into the effects of aircraft noise on sleep dates back more than 20 years. Since then, traffic patterns and the noise levels produced by single aircraft have changed substantially. It is therefore important to acquire current data on sleep disturbance relative to varying degrees of aircraft noise exposure in the U.S. that can be used to check and potentially update the existing noise policy. This manuscript describes the design, procedures, and analytical approaches of the FAA's National Sleep Study. Seventy-seven U.S. airports with relevant nighttime air traffic from 39 states are included in the sampling frame. Based on simulation-based power calculations, the field study aims to recruit 400 participants from four noise strata and record an electrocardiogram (ECG), body movement, and sound pressure levels in the bedroom for five consecutive nights. The primary outcome of the study is an exposure-response function between the instantaneous, maximum A-weighted sound pressure levels (dBA) of individual aircraft measured in the bedroom and awakening probability inferred from changes in heart rate and body movement. Self-reported sleep disturbance due to aircraft noise is the secondary outcome that will be associated with long-term average noise exposure metrics such as the Day-Night Average Sound Level (DNL) and the Nighttime Equivalent Sound Level (Lnight). The effect of aircraft noise on several other physiological and self-report outcomes will also be investigated. This study will provide key insights into the effects of aircraft noise on objectively and subjectively assessed sleep disturbance.

Comparative Analysis of Noise and Vibration for Dual Three-Phase IPMSM Under Healthy and Multi-Phase Open-Circuit Fault Operations

The dual three-phase interior permanent magnet synchronous machines (IPMSMs) exhibit excellent fault-tolerant capabilities due to their multi-phase winding configurations. Under certain winding failure circumstances, by using the fault tolerant control (FTC) to reconstruct the normal rotating magnetomotive force, the machine can still provide the expected comparable torque as the healthy mode does. However, in the existing literature, limited attention was paid to the noise and vibration (NV) problems targeting the dual three-phase IPMSMs in FTC operation. To fill this knowledge gap, this paper conducts a quantitative comparison on the NV performance of a dual three-phase IPMSM under healthy and multi-phase open-circuit fault conditions under FTC. The comparative studies involve radial electromagnetic force, acceleration distribution, sound pressure level as well as machine housing deformation, which are analyzed under healthy and multi-phase open-circuit fault operations. Based on our exclusive findings, after applying the FTC, even though the machine can deliver the desired electromagnetic performance, the maximum deformation and sound pressure level of the IPMSM can be mitigated by 12.9% and 16.9%, respectively, compared to the ones under the faulty condition without FTC.

Experimental investigation on the hydro-acoustic characteristics of tandem cylinders with equal diameters

The investigation of the hydro-acoustic characteristics of tandem cylinders has a great importance because they occur in a variety of maritime applications that include submarines, offshore structures and seabed pipelines systems. Better understanding of the noise generation mechanism of tandem cylinders provides great contribution to reduce noise levels for many engineering applications. In this study, the hydro-acoustic characteristics of tandem cylinders with same diameter were experimentally investigated for five different distance ratios at Reynolds number of 1.6 × 104. The diameter of the front and rear cylinders used in hydro-acoustic experiments is 0.02 m. It is observed that the main peak spectrum becomes narrower as the distance ratio increases. The width of the main peak spectrum also decreases as the flow regime transition from the reattachment regime to the separation regime. An increase in the distance ratio is found to correspond to an increase in the main peak frequency. The maximum sound pressure level is observed to attain its peak value at the critical distance ratio of 3.0. Notably, the maximum sound pressure level exhibits a substantial increase of approximately 6 dB as the distance ratio increases from 1.5 to 3.0, followed by a subsequent decrease of approximately 1 dB between the distance ratios of 3.0 and 6.0.

Vortex effects on aerodynamic performance of multi-stage continuous-resistance trim under high pressure gradient

The multi-stage continuous-resistance trim (MSCRT) is widely utilized in gas turbine combined-cycles (GTCC), acting as an indispensable throttling component used for regulating fluid pressure, flow rate and temperature. However, under harsh operating conditions, the flow in MSCRT becomes unstable, leading to disrupted aerodynamic performance and increased energy consumption. Despite its significance, the underlying vortex dynamics and its correlation with aerodynamic performance remain elusive. To address this, a comprehensive investigation into the unsteady flow of MSCRT is proposed, combining experimental and numerical methods. The vortex dynamics mechanism is revealed, and then, the vortex effects on pressure pulsation and aerodynamic performance are investigated. Results show that the novel design allows the pressure gradient to be dissipated between the layers and succeeds in achieving effective control of noise and energy consumption. Based on the aerodynamic design, the mutual correspondence between the vortical structure and the flow field results is verified. Furthermore, the relationship between the instantaneous total vorticity and the pressure pulsation is established, as well as the relationship between the vortex parameters and the maximum sound pressure level. Notably, a linear correlation between the maximum sound pressure level and the maximum instantaneous total vorticity is determined. This study provides support for improving the aerodynamic performance of related throttling components.