Cavity Thickness Research Articles

Numerical investigation on the cloud cavitating flow over a Clark Y foil under free surface effect

For a high-speed vehicle in the presence of cavitating flow while operating near the free surface, the interaction between the cavitating flow and the free surface can be very critical. In this paper, the cloud cavitating flow over a Clark Y foil near the free surface was investigated via numerical approaches. The large eddy simulation (LES) turbulence model, the volume of fluid (VOF) method, as well as the Schnerr Sauer cavitation model were used in the simulation to solve for the cloud cavitation flow region and capture the interphase between the multiphase (air, water and vapour). The analysis centred on the results of the two- (2D) and three-dimensional (3D) cases for the Clark Y foil at various submerged depths for several evolution cycles. The free surface affects the cavity profile, evolution period, re-entrant jet inside/beneath the cavity and hydrodynamic coefficients. The cavity has become shorter and thicker under the free surface effect. Induced by the re-entrant jet thickness, the cavity becomes more stable as the submerged depth decreases. The cavity evolution, the cavity length and thickness of different cycles are similar, while the shedding cavity can delay the evolution. A similar phenomenon can be observed in 3D, but the flow structure is more complex than in 2D. The 3D effect likewise manifests as shortening the cavity length while changing the direction of the re-entrant jet inside/beneath the cavity.

In-line steady shear flow characteristics of polymer melt in rectangular slit cavities during thin-wall/micro injection molding

Both scale and temperature field effects have a considerable impact on polymer melt viscosity during thin-wall/micro injection molding. In this work, an in-line rheological test with similar dynamic test conditions to thin-wall/micro injection molding was adopted to further analyze the rheological properties and improve the simulation accuracy. An injection mold with rectangular slit cavity and storage region was designed to obtain a steady flow. The effects of factors such as the cavity size, viscous dissipation and melt temperature on polymer melt viscosity were studied. The results demonstrate that the injection molding conditions have a significant influence on the in-line rheological properties. When the cavity thickness (h) was 0.5 mm, the average percentage reductions of viscosity were 8.86 % (200 to 220 °C) and 4.07 % (220 to 240 °C) as the melt temperature rose. They were 57.13 % (200 to 220 °C) and 38.86 % (220 to 240 °C) when the cavity thickness was reduced to 0.2 mm. The test results show that the average prediction errors of pressure drop based on the capillary rheometer viscosity and in-line viscosity are 29.78 % (die: 5/0.2 mm) and 16.61 % (slit:h = 0.2 mm), respectively. In-line rheological viscosity shows potential for application in mold flow simulation.

Fiber Fabry-Perot Demodulation System Based on Dual Fizeau Interferometers

In this study, we present a dual-Fizeau-interferometer-based high-speed and wide-range fiber-optic Fabry-Perot (F-P) demodulation system. We employ two Fizeau interferometers with air cavity thickness satisfying the quadrature requirement to increase the demodulation speed and broaden the demodulation range in order to address the issues of the existing fiber F-P demodulation system’s sluggish demodulation rate and limited range. In order to investigate the demodulation properties of the dual-Fizeau-interferometer-based demodulation system, we derive and create a theoretical model of the system. The theoretical model, which primarily consists of the structural design of the interferometer and the study of the center wavelength of the light sources and their bandwidth selection, is used to construct the optical structure of the demodulation system. According to the calculation results, the demodulated signal exhibits the best contrast ratio when the two light sources’ respective center wavelengths are 780 nm and 850 nm, and their bandwidths are 28 nm and 30 nm. Finally, we finish evaluating the demodulation system’s demodulation performance, parameter calibration, and assembly debugging. The test results demonstrate the constant operation of the demodulation system, an update rate of 100 kHz, a demodulation range of 4.74 µm, and a cavity length resolution of approximately 5 nm. Additionally, the system can perform high speed demodulation thanks to the light emitting diode’s (LED’s) nanosecond level switching speed and the usage of a single point detector.

Numerical and experimental study of the dynamic thermal resistance of ventilated air-spaces behind passive and active façades

The variation of the thermo-hydrodynamic behavior of the airflow in the ventilated cavity behind external claddings in a wall structure could potentially affect the overall thermal resistance of the entire structure. Although the impact of an enclosed air-space in the wall on the total R-value of the assembly has been thoroughly investigated in the literature, it has not been addressed for a ventilated cavity. In the present study, as a first step, plausible definitions to determine the thermal resistance of the ventilated cavity behind external claddings in transient conditions are described. As the second step, the dynamic thermal resistance of the naturally ventilated air-spaces behind passive (i.e., brick and fiber cement) claddings and active (i.e., BIPV) facades are studied using two approaches. In the first approach, a 2-D numerical model validated against measurements is employed to compute the thermal resistance of the ventilated air gap under different conditions. Accordingly, the impact of the cladding type, seasonal variation, cavity thickness, and presence of the reflective insulation in the air gap on the dynamic change of the thermal resistance of the air-space is analyzed. In the second approach, in-field measurements are performed in a test facility to experimentally examine the contribution of the thermal resistance of the cavity to the total R-value of the wall structure. The results obtained from both approaches are compared with the design values calculated based on the ISO 6946:2017 and ISO 9869–1:2014 standards. The results reveal that the dynamic change of the thermal resistance of the air gap during a day could be captured using numerical simulations. It is shown that the daily averaged thermal resistance of the cavity could reach up to 47 times higher than the design R-value of the BIPV façade. The experimental measurements confirm that the thermal resistance of the ventilated air-space could converge to a steady-state value after a certain duration of time following the requirements provided in the standards, which could be practically used for the code-compliant analysis. It is also observed that the ventilated cavity could act as an insulation layer with higher thermal resistance compared to some of the solid materials used in the wall assembly.

Ultrafast light emission at telecom wavelengths from a wafer-scale monolayer graphene enabled by Fabry-Perot interferences.

Ultrafast light emission from monolayer graphene shows attractive potential for developing integrated light sources for next-generation graphene-based electronic-photonic integrated circuits. In particular, graphene light sources operating at the telecom wavelengths are highly desired for the implementation of graphene-based ultrahigh-speed optical communication. Currently, most of the studies on ultrafast light emission from graphene have been performed in the visible spectrum, while studies on ultrafast emission at the telecom wavelengths remain scarce. Here, we present experimental observations of strong ultrafast thermal emission at telecom wavelengths from wafer-scale monolayer graphene. Our results show that the emission spectra can be strongly modified by the presence of the cavity effect to produce an enhanced emission at telecom wavelengths. We corroborate our experimental results with simulations and show that by designing a suitable cavity thickness, one can easily tune the emission profile from visible to telecom wavelength regardless of the pump power. In addition, we demonstrate that the insertion of a monolayer of hexagonal boron nitride between graphene and the substrate helps improve the thermal stability of graphene, thereby providing more than five times enhancement of the ultrafast thermal emission. Our results provide a potential solution for stable on-chip nanoscale light sources with ultrahigh speed modulation.

Numerical analysis of additional heat loss induced by air cavities between insulation boards due to non-ideality

This study uses the numerical steady-state three-dimensional CFD calculation method to assess parametrically the thermal transmittance of a building envelope with partially and fully penetrating air cavities within 20 cm thick layer of insulation. Heat flux measurements from climate chamber experiment were used to validate numerical model and estimated heat flux at different height of penetrating air cavity. Focus is on the effect of different cavity geometry and cavity location within a building envelope, including the effect of temperature difference across the building envelope. Fully penetrating horizontal air cavities in the wall construction and vertical air cavities inside the floor construction were found to have an insignificant effect on thermal transmittance. The vertical air cavities in the wall and the roof construction significantly increase the convective heat transfer through the insulation layer, well over the normative correction levels defined by EN ISO 6946. The effect is strongly dependent on the temperature difference and cavity thickness. At 40 K temperature difference, the penetrating air cavities with 5, 10 and 20 mm thickness will increase the thermal transmittance up to 10, 33 and 59% respectively; the simplified procedure in EN ISO 6946 was unable to describe this effect adequately. For an upward heat flow in the roof construction, the effect was even more adverse. Using dual layer insulation with rebate, tongue and groove edge or expanding montage foam to tighten the external side of the air cavity, additional heat loss is reduced roughly by half and the dependency of additional heat loss on the temperature difference between internal and external environments is decreased.

A highly sensitive Nano Gap Embedded AlGaN/GaN HEMT sensor for Anti-IRIS antibody detection

This study investigates the feasibility of Nano gap embedded AlGaN/GaN HEMT to sense antibody-antigen reaction. The sensor can detect the binding response of a typical antibody Ixodes ricinus immunosuppressor (anti-Iris) protein in Nano cavity. The sensor performance is analyzed by the change in electrical characteristics by the anti-iris antibody and iris antigen interaction. The device performance is optimized independently by varying cavity thickness, cavity length, biomolecule length, and Al composition. The output drain current recorded at VDS = 10V was linearly incremented with the length of the bio layers. The increase in cavity thickness and length will reduce the sensitivity due to a reduction in the cavity fill-in factor. The maximum sensitivity obtained is 169% at a cavity thickness of 10 nm and cavity length of 100 nm with 30% Al content. Silvaco Atlas simulation software has simulated and optimized the proposed device structure.

Numerical analysis of ventilated cavitating flow around an axisymmetric object with different discharged temperature conditions

Nowadays, with the widespread use of modern technology in underwater vehicles, particularly in naval applications, the artificial gas ejected from ventilated holes is normally heated because of engine operations. However, the dynamics of ventilated hot gas have not yet been fully studied. In this study, the cavitating flow around an axisymmetric body with different ventilated temperatures was numerically investigated. A fully compressible mixture model based on a homogeneous multiphase approach was employed. A high-order accuracy flow solver based on the numerical models of a dual-time preconditioning technique, a sharp interface-capturing scheme, and an enhanced cavitation model was used to examine the effects of temperature on the cavitating flow. First, the numerical results were validated by comparison with available experimental data of cavitating flow around a conical cavitator. Reasonable agreements on the cavity shape, cavity length, and cavity thickness were achieved. The solver was then applied in simulations to analyze the development of the ventilated cavity, including the cavity formation at the early stage, the re-entrant jet phenomenon, and the cavity shedding mechanism. In addition, the effects of ventilated temperatures on the cavity length and cavity thickness were studied. Further insight into the distributions of the flow field inside the cavity, and the instability of the gas-water interface when temperature increases were also provided.

Miniaturization of Triple-Mode Wideband Bandpass Filters

In this article, a class of wideband bandpass filters (BPFs) using triple-mode coaxial resonators has been introduced. Each triple-mode resonator is utilized with TM <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">010</sub> mode, TE− mode, and TE+ mode orthogonal to each other. Two L-shaped feeding probes and a loading disk are adopted to implement the miniaturization of these wideband BPFs. To observe the degree of miniaturization, we set a design specification of the same fractional bandwidth (FBW) of 40% at the same central frequency of 2.5 GHz. After employing the L-shaped feeding probes and loading disk, the efficient circuit size without cavity thickness is reduced by 80% compared with the triple-mode wideband filter without L-shaped feeding probes and loading disk. In contrast, the unloaded quality factors are slightly changed. In addition, another advantage of this work is that the upper stopband is extended to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.5f_{0}$ </tex-math></inline-formula> . Three experimental wideband BPFs in the large, medium, and small sizes are designed, manufactured, and tested for demonstration. Good agreements are obtained between simulation and experiment.

A Quantitative Analysis on Key Factors Affecting the Thermal Performance of the Hybrid Air-Based BIPV/T System

Air-based BIPV/T is of significant research interest in reducing energy load and improving indoor comfort. As many factors related to meteorology, geometry and operation contribute to the thermal performance of BIPV/T, especially for one kind of hybrid air-based BIPV/T (HAB-BIPV/T), quantifying the effects of such uncertain parties is essential. In this paper, a numerical analysis was conducted regarding 13 parameters of one HAB-BIPV/T prototype. For each quantity of interest, the kernel density estimate was regarded as an approximation to the probability density function to assess uncertainty propagation. A sequential sensitivity analysis was used to quickly screen (by Morris) and exactly quantify (by Sobol’) the effects of significant variables. The surrogate model based on a back propagation neural network was employed to dramatically reduce the computational cost of Monte Carlo analysis. The results show that the uncertain inputs discussed can induce considerable fluctuations in the three quantities of interest. The most significant parameters on AUI include air inlet height, cavity thickness, air inlet velocity and number of air inlets. The outcomes of this study provide insights into the correlation between various factors and the thermal efficiency of the HAB-BIPV/T as a reference for similar design works.

Influence of the injection molding thermal boundary conditions on the filling flow of PET

During the filling phase of the injection molding process, the polymer in contact with the wall solidifies, developing the so-called skin layer. Although the no-flow temperature is often exploited in numerical simulations to model the skin layer formation mechanism, there is still an incomplete understanding of what happens for semi-crystalline PET. In fact, for this polymer, the high shear stresses near the cavity wall combined with the thermal gradient at the polymer-mold interface can cause the so-called flow-induced crystallization. This work aims to experimentally investigate the skin layer formation at different injection molding processing conditions. A full-factorial experimental plan was performed using a commercial PET injected into an open-cavity mold. The thermal and mechanical boundary conditions at the polymer-wall interface were varied using insulating coatings and different flow rates, respectively. The mold coatings were applied to different steel substrates to consider the substrate thermal conductivity contribution. Different flow rates were imposed, varying the cavity thickness and the injection speed. The in-line acquisition of the cavity pressure allows for assessing the contributions of the modified boundary conditions to the solidified skin layer formation. The results show that the insulating mold coating changes the thermal boundary conditions, leading to a maximum pressure decrease of 14 %. The cavity pressure vs. filling time curves for the uncoated inserts show an evident derivative discontinuity, suggesting the onset of flow-induced crystallization.

Development Of A Turbulent Boundary Layer Over An Air Cavity

The turbulent boundary layer development over an air cavity is studied experimentally using planar Particle Image Velocimetry. An identification technique based on the gradient of correlation values was employed to detect the cavity interface which revealed a well-defined, asymmetric bump-like geometry at the spanwise-uniform region of the cavity. No separation was observed at the leeward side of the cavity, owing largely to the high boundary layer thickness to maximum cavity thickness ratio (δ/tmax ≈ 11.8). The shape of the cavity was found to dictate the turbulent boundary development by subjecting it to alternating streamwise pressure gradients: from an adverse to a favourable and back to an adverse, moving downstream along the cavity. Profiles o f mean s treamwise velocity and turbulent stresses show the alternate pressure gradients and air injection to be the dominant perturbations to the flow, with streamline curvature only having a minor influence, also based on previous observations.

Molecular Vibrational Polaritons Towards Quantum Technologies

AbstractMolecular vibrational polaritons (MVPs)—a hybrid molecular‐photon quasiparticle—and the development of a proof‐of‐principle quantum technology platform are discussed to simulate coherence transfer, for use at room temperature. It is shown that MVPs can form qubits, coherence, and have nonlinear interactions, all at room temperature. Some new insights, such as polaritonic nonlinearity dependence on macroscopic properties including cavity thickness and molecular concentrations are also uncovered. It is hoped that these advances can stimulate more research in developing this system into a quantum technology platform free from the constraints imposed by the requirement of cryogenic conditions.

State of Charge and Capacity Tracking in Vanadium Redox Flow Battery Systems

The vanadium redox flow battery electrolyte is prone to several capacity loss mechanisms, which must be mitigated to preserve electrolyte health and battery performance. This study investigates a simple and effective technique for the recovery of capacity loss arising from symmetrical mechanisms via automatic electrolyte rebalancing. However, chemical or electrochemical techniques must be used to mitigate capacity loss from asymmetrical mechanisms (e.g., air oxidation of V2+), which requires knowledge of the oxidation states present in the electrolytes. As such, this study assesses the suitability of SOC tracking via electrolyte absorption for independent monitoring of the anolyte and catholyte within an existing VRFB system. Testing is performed over cycling of a 40 cell, 2.5 kW with 40 L of electrolyte. Optical monitoring is performed using a custom-made flow cell with optical paths (interior cavity thicknesses) ranging from 1/4″ to 1/16″. Light transmitted through the cell by a 550 lumen white light source is monitored by a simple photodiode. The electrolyte rebalancing mechanism displayed success in recovering symmetrical capacity losses, while optical monitoring was unsuccessful due to the high absorbance of the electrolyte. Potential improvements to the monitoring system are presented to mitigate this issue.

Impression metadiaphyseal fractures of the proximal end of the leg bones and our experience

Introduction: Impression fractures of the proximal end of the tibia occupy the main place in the appearance of defor-mation of the articular surfaces. The goal is to improve the results of treatment of impression fractures of the proximal end of the shin bones, based on clarifying the volume of impression defects and filling the residual cavities. Materials and methods: The study analyzed the data of 32 patients with impression fractures of the proximal end of the tibia. The volume of the formed cavities was determined according to the program for the MSCT study (per cubic centimeter measurements). V = length *thickness *width *0.52 = cubic cm, the method by which radiation diagnostics doctors work and display the volume of the cavity in cubic centimeters. V cavity volume = cavity length *cavity thickness *cavity width *0.52 = cc / cm (0.52 is the accepted average value, standard). Results: The results were also studied according to the accepted methodology compiled by the crite-ria for evaluating the results, and they turned out to be the following in terms of the totality of the treatment performed: in 25 patients it was from 62 to 76 points, i.e. good, in 7 patients they were satis-factory, i.e. averaged 58 points, there were no unsatisfactory result. Discussion: The combined use of PRP-therapy, bone grafting or bone impregnated with platelet mass proved to be compatible in osteosynthesis of bone fragments using the Ilizarov apparatus. Conclusion: The use of modern visualization diagnostic tools determines the volume and calculations for filling bone defects.

Design and Simulation Experiment of Rigid-Flexible Soft Humanoid Finger

This paper is based on the “Fast Pneumatic Mesh Driver” (FPN) used to couple a silicone rubber soft body with a rigid skeleton. A rigid-flexible coupling soft-body human-like finger design scheme is proposed to solve the problem of low load on the soft-body gripping hand. The second-order Yeoh model is used to establish the statics model of the soft humanoid finger, and the ABAQUS simulation analysis software is used for correction and comparison to verify the feasibility of the soft humanoid finger bending. The thickness of the driver cavity and the confining strain layer were determined by finite element simulation. The mold casting process is used to complete the preparation of human-like fingers and design a pneumatic control system for experiments combined with 3D printing technology. The experimental results show that the proposed rigid-flexible coupling soft body imitating the human finger structure can realize the corresponding actions, such as the multi-joint bending and side swinging, of human fingers. Compared with the traditional pure soft-body finger, the fingertip output force is significantly improved. The optimal design and simulation analysis of the human gripper and the feasibility of the application have practical guiding significance.

Distributed Bragg Reflectors Employed in Sensors and Filters Based on Cavity-Mode Spectral-Domain Resonances.

Spectral-domain resonances for cavities formed by two distributed Bragg reflectors (DBRs) were analyzed theoretically and experimentally. We model the reflectance and transmittance spectra of the cavity at the normal incidence of light when DBRs are represented by a one-dimensional photonic crystal (1DPhC) comprising six bilayers of TiO/SiO with a termination layer of TiO. Using a new approach based on the reference reflectance, we model the reflectance ratio as a function of both the cavity thickness and its refractive index (RI) and show that narrow dips within the 1DPhC band gap can easily be resolved. We revealed that the sensitivity and figure of merit (FOM) are as high as 610 nm/RIU and 938 RIU, respectively. The transmittance spectra include narrow peaks within the 1DPhC band gap and their amplitude and spacing depend on the cavity’s thickness. We experimentally demonstrated the sensitivity to variations of relative humidity (RH) of moist air and FOM as high as 0.156 nm/%RH and 0.047 %RH, respectively. In addition, we show that, due to the transmittance spectra, the DBRs with air cavity can be employed as spectral filters, and this is demonstrated for two LED sources for which their spectra are filtered at wavelengths 680 nm and 780 nm, respectively, to widths as narrow as 2.3 nm. The DBR-based resonators, thus, represent an effective alternative to both sensors and optical filters, with advantages including the normal incidence of light and narrow-spectral-width resonances.

Effects of Cavity Conditions on Transcription Molding of Microscale Prism Patterns Using Ultra-High-Speed Injection Molding

Abstract Ultra-high-speed injection molding has been reported to be a very effective method for improving transcription molding. In this study, by using stampers with V-grooves having pitches of 25 μm and 100 μm, we investigated the effects of cavity conditions, including cavity thickness, groove layout, and groove pitch size, on transcription molding. These experiments were also conducted under various molding conditions such as injection rates, melt and mold temperatures, and holding pressure, etc. As a result, it was found that the groove layout of a stamper remarkably affects transcription fidelity and these effects do not disappear when the molding is performed with a cavity-vacuum process. This phenomenon was explained using the well-known molecular orientation by the extensional flow during injection molding. When transcription molding was performed with cavities of different thicknesses (0.5 mm, 1.0 mm, and 2.0 mm), the effect of holding pressure on transcription was inversely related to the cavity wall thickness. This result indicates that, in the molding with a thin cavity wall, the transcription mainly completed during the filling stage. In addition to the shortening of cavity filling time and decrease in viscosity by shear heating, an accelerated increase in cavity pressure during the cavity filling stage was also found to be important for explaining the improvement in transcription with ultrahigh-speed injection molding.

Effect of electrode separation and electrode backscatter thickness of a parallel plate ionization chamber on the measurement of dose to tissue in beta radiation fields

Plane parallel plate ionization chamber (PPC) is used in dosimetry especially for beta particles and low energy electron beam. The response of the PPC is affected by the electrode separation, thickness and material of backscatterer. The effect of electrode separation arises due to the well-known inscattering effect of electron which causes fluence perturbation inside the chamber cavity. The perturbation is caused due to reduced electron scattering in the chamber cavity compared to an ideal phantom material and it depends on the thickness of the cavity. Furthermore, the response of PPC also gets affected by the material behind the air cavity. Variation in the response depends on the thickness and the atomic number of the material behind collecting electrode of the PPC. The theoretical studies on the effect of collecting electrode backscatter thickness and electrode separation on the response of a PPC used as a transfer standard in ISO 6980 reference beta radiation field from 85Kr, 90Sr–90Y and 106Ru–106Rh radionuclides are presented. Multi-particle transport code FLUKA is used for the studies. The Polymethyl Methacrylate (PMMA) plate having 3.5 mm thickness is found to provide full backscatter for the above beta radionuclides. It is also observed that even for a well-guarded PPC, as the chamber electrode separation increases, the measured depth dose curve deviates from the ideal depth dose curve and the effective point of measurement (EPOM) of the PPC shifts towards downward direction from chamber reference point. It is also observed that the deviation between ideal and measured depth dose curve (related to EPOM shift) depends on the cavity thickness of the PPC. In the present work, optimization of design parameters of a PPC is carried out to establish it as a transfer standard in compliance with ISO 6980 for the standardization of reference beta radiation fields from 85Kr, 90Sr–90Y and 106Ru–106Rh radionuclide.

The structure of near-wall re-entrant flow and its influence on cloud cavitation instability

The so-called ‘re-entrant jet’ is fundamental to periodic cloud shedding in partial cavitation. However, the exact physical mechanism governing this phenomenon remains ambiguous. The complicated topology of the re-entrant flow renders whole-field, detailed measurement of the re-entrant flow cumbersome. Hence, most studies in the past have derived a physical understanding of this phenomenon from qualitative analyses of the re-entrant jet. Thus, quantitative studies are scarce in the literature. In this work, we present a methodology to experimentally measure the re-entrant flow below the vapour cavity in an axisymmetric venturi. The axisymmetry of the flow geometry is exploited to image tracer particles in the near-wall re-entrant flow. The main objective of employing tomographic imaging and subsequent velocimetry is to resolve the thickness and the velocity of the re-entrant flow. Additionally, phase-averaging conditioned on cavity length sheds light on the temporal evolution of re-entrant flow in a shedding cycle. The measured re-entrant film is as thick as sim 1.2 mm for a maximum cavity length of sim 0.9 D_{t}, where D_{t} is the venturi throat diameter. However, the re-entrant film thickness at higher cavitation number is measured to be about 0.5 mm. Further, the re-entrant flow is seen to attain a maximum velocity up to half the throat velocity as the vapour cavity grows in time and the re-entrant flow thickens. We observe that a complex spatio-temporal evolution of re-entrant flow is involved in the cavity detachment and periodic cloud shedding. Finally, we apply the demonstrated methodology to study the evolution of the near-wall liquid flow, below the vapour cavity in different cavity shedding flow regimes. The role of two main mechanisms responsible for cloud shedding, i.e. (i) the adverse-pressure gradient driven re-entrant jet, and (ii) the bubbly shock wave emanating from the cloud collapse are quantitatively assessed. We observe that the thickness of the re-entrant liquid film with respect to the cavity thickness can influence the cavity shedding behaviour. Further, we show that both the mechanisms could be operating at a given flow condition, with one of them dominating to dictate the cloud shedding behaviour.Graphical abstract