Valve Dynamics Research Articles

Dynamics and experimental study of a novel proportional directional valve with displacement feedback groove controlled by high-speed switching valves

The intelligence of hydraulic roof support is an important guarantee for unmanned fully mechanized coal mining face. The water-based medium proportional directional valve is the main factor that restricts the intelligent realization of support system. The support control valve needs to meet the 2/3 (two-position three-way) structure, taking into account both manual and electro-hydraulic control functions. The current water-based proportional valve does not satisfy the structural or functional demands of the support system. In this paper, a novel 2/3 water-based proportional directional valve is presented based on the displacement-flow feedback principle, which has two control modes: manual on-off control and electro-hydraulic proportional control. The proportional valve comprises two main valve spools and two pilot valves. The pilot valve is composed of a 2/3 on-off valve with manual operation capability and a high-speed switching valve group controlled by PWM (Pulse Width Modulation). The mathematical model of the proportional valve is established, and the experimental system is built to verify the characteristics of proportional valve. The proportional valve can meet the special functional requirements of the support. In the proportional control mode, the adjustment of spool displacement is regulated through the modulation of PWM duty ratio, resulting in effective control performance of the proportional valve. Furthermore, the discontinuous flow of the high-speed switching valve causes the pressure fluctuation of the pilot hydraulic bridge. Increasing the carrier frequency of PWM can reduce the amplitude of control chamber pressure and spool displacement fluctuation. The findings of the study can offer valuable insights for the continued advancement and enhancement of water-based proportional valves used in hydraulic roof support systems.

Unraveling aortic hemodynamics using fluid structure interaction: biomechanical insights into bicuspid aortic valve dynamics with multiple aortic lesions.

Aortic lesions, exemplified by bicuspid aortic valves (BAVs), can complicate congenital heart defects, particularly in Turner syndrome patients. The combination of BAV, dilated ascending aorta, and an elongated aortic arch presents complex hemodynamics, requiring detailed analysis for tailored treatment strategies. While current clinical decision-making relies on imaging modalities offering limited biomechanical insights, integrating high-performance computing and fluid-structure interaction algorithms with patient data enables comprehensive evaluation of diseased anatomy and planned intervention. In this study, a patient-specific workflow was utilized to biomechanically assess a Turner syndrome patient's BAV, dilated ascending aorta, and elongated arch. Results showed significant improvements in valve function (effective orifice area, EOA increased approximately twofold) and reduction in valve stress (~ 1.8-fold) following virtual commissurotomy, leading to enhanced flow dynamics and decreased viscous dissipation (~ twofold) particularly in the ascending aorta. However, increased viscous dissipation in the distal transverse aortic arch offset its local reduction in the AAo post-intervention, emphasizing the elongated arch's role in aortic hemodynamics. Our findings highlight the importance of comprehensive biomechanical evaluation and integrating patient-specific modeling with conventional imaging techniques for improved disease assessment, risk stratification, and treatment planning, ultimately enhancing patient outcomes.

Three-dimensional simulation of cavitating flow in reciprocating positive displacement pumps with fluid-actuated valves

Abstract An in-house compressible three-dimensional (3D) finite volume Computational Fluid Dynamics (CFD) method, with statistical turbulence model and moving grid capabilities, is presented and applied to the suction stroke of a simplex plunger positive displacement pump. The approach utilizes a pressure-based implicit solution algorithm and a mass transfer cavitation model. Fluid-actuated valve dynamics are approximated using a fluid-structure interaction algorithm. The closed valve and early phase of valve opening are approximated by a permeable wall. A circular segment model is introduced, significantly reducing computing time. Experimental validation is performed by time-resolved pressure and flow rate measurements, as well as high-speed visualizations of the valve dynamics. A speed variation is conducted to investigate harmless advanced and erosive distinctive partial cavitation. The simulation reproduces the delay of cavity collapse, observed with increasing speed, and reveals distinctive void patterns related to the chamber pressure time progression. These void patterns are fundamental for understanding the cavitation dynamics and potential erosion risk in the system. Deviations from data remain in the flow phase subsequent to the collapse due to overestimated wave reflection at the inlet boundary in the suction pipe.

Numerical modeling of heat transfer mechanism in remote sensing bulb of thermal expansion valves

Thermal management of automotive systems has garnered a lot of focus in recent times to improve the energy efficiency of vehicles and address the challenge of global warming. In combustible fuel vehicles, the heat pump compressor is driven by the engine power which leads to changes in operating condition of the cycle while the vehicle is in motion. In electric vehicles, a combined thermal management strategy handles both cabin and battery pack cooling/heating depending on the ambient conditions and power requirements by adjusting refrigerant flow rates and flow directions with sophisticated valves. Irrespective of the vehicle type, effective variable refrigerant flow control is prerequisite to ensure optimum thermal comfort with minimum energy. Thermal expansion valves (TXV) are the most widely used method for regulating mass flow rate of refrigerant during the expansion step of the vapor compression cycle based on the principle of trying to maintain a fixed degree of superheat at the evaporator outlet. Conventional models of the thermal expansion valve ignore the time lag between fluctuation of temperature at the evaporator outlet and the corresponding change in pressure of the TXV remote sensing bulb, treating the valve as an instantaneous element during transient operation. This paper presents a novel method for determining the temperature profile and time constant of the remote sensing bulb response using numerical methods, in an attempt to capture the dynamics of thermal expansion valve in active heat pump cycle. Finite difference method was used to solve for the conduction heat transfer between the bulb and the heat exchanger outlet tube in perfect thermal contact applying the necessary boundary conditions. This improved modeling approach will be helpful in better prediction of the dynamic behavior of thermal expansion valves and how it influences the evaporative heat exchanger performance during transient operations to determine control algorithm and strategies.

A review of polymeric heart valves leaflet geometric configuration and structural optimization

Valvular heart disease (VHD) is a major cause of loss of physical function, quality of life and longevity, and its prevalence is growing worldwide due to increased survival rates and an aging population. The most common treatment for VHD is surgical heart valve replacement with mechanical heart valves (MHVs) and bioprosthetic heart valves (BHVs), but with different limitations. Polymeric heart valves (PHVs) exhibit promising material properties, valve dynamics and biocompatibility, representing the most feasible alternative to existing artificial heart valves. However, inadequate fatigue performance remains a critical obstacle to their clinical translation. In this case, geometry and material design are essential to obtain the best mechanical properties of the PHV. In this study, we summarized the effects of optimal design of PHVs from geometrical configuration optimization (valve height, thickness and design curve) and structural material optimization (anisotropy, fiber reinforcement, variable thickness, microstructure and asymmetric optimization), and selected the parameters including Effective Orifice Area (EOA), Regurgitant fraction (RF), and Stress Distribution to compare the performance of valves. It would provide the theoretical support for the optimal design of PHVs.

A quasilinear hyperbolic one-dimensional model of the lymph flow through a lymphangion with valve dynamics and a contractile wall

This paper presents a one-dimensional model that describes fluid flow in lymphangions, the segments of lymphatic vessels between valves, using quasilinear hyperbolic systems. The model incorporates a phenomenological pressure-cross-sectional area relationship based on existing literature. Numerical solutions of the differential equations align with known results, offering insights into lymphatic flow dynamics. This model enhances the understanding of lymph movement through the lymphatic system, driven by lymphangion contractions.

Computational haemodynamics for pulmonary valve replacement by means of a reduced fluid-structure interaction model.

Pulmonary valve replacement (PVR) consists of substituting a patient's original valve with a prosthetic one, primarily addressing pulmonary valve insufficiency, which is crucially relevant in Tetralogy of Fallot repairment. While extensive clinical and computational literature on aortic and mitral valve replacements is available, PVR's post-procedural haemodynamics in the pulmonary artery and the impact of prosthetic valve dynamics remain significantly understudied. Addressing this gap, we introduce a reduced Fluid-Structure Interaction (rFSI) model, applied for the first time to the pulmonary valve. This model couples a three-dimensional computational representation of pulmonary artery haemodynamics with a one-degree-of-freedom model to account for valve structural mechanics. Through this approach, we analyse patient-specific haemodynamics pre and post PVR. Patient-specific geometries, reconstructed from CT scans, are virtually equipped with a template valve geometry. Boundary conditions for the model are established using a lumped-parameter model, fine-tuned based on clinical patient data. Our model accurately reproduces patient-specific haemodynamic changes across different scenarios: pre-PVR, six months post-PVR, and a follow-up condition after a decade. It effectively demonstrates the impact of valve implantation on sustaining the diastolic pressure gradient across the valve. The numerical results indicate that our valve model is able to reproduce overall physiological and/or pathological conditions, as preliminary assessed on two different patients. This promising approach provides insights into post-PVR haemodynamics and prosthetic valve effects, shedding light on potential implications for patient-specific outcomes.

Fluid-structure interaction analysis of a healthy aortic valve and its surrounding haemodynamics.

The opening and closing dynamics of the aortic valve (AV) has a strong influence on haemodynamics in the aortic root, and both play a pivotal role in maintaining normal physiological functions of the valve. The aim of this study was to establish a subject-specific fluid-structure interaction (FSI) workflow capable of simulating the motion of a tricuspid healthy valve and the surrounding haemodynamics under physiologically realistic conditions. A subject-specific aortic root was reconstructed from magnetic resonance (MR) images acquired from a healthy volunteer, whilst the valve leaflets were built using a parametric model fitted to the subject-specific aortic root geometry. The material behaviour of the leaflets was described using the isotropic hyperelastic Ogden model, and subject-specific boundary conditions were derived from 4D-flow MR imaging (4D-MRI). Strongly coupled FSI simulations were performed using a finite volume-based boundary conforming method implemented in FlowVision. Our FSI model was able to simulate the opening and closing of the AV throughout the entire cardiac cycle. Comparisons of simulation results with 4D-MRI showed a good agreement in key haemodynamic parameters, with stroke volume differing by 7.5% and the maximum jet velocity differing by less than 1%. Detailed analysis of wall shear stress (WSS) on the leaflets revealed much higher WSS on the ventricular side than the aortic side and different spatial patterns amongst the three leaflets.

Image-Based Computational Fluid Dynamics to Compare Two Repair Techniques for Mitral Valve Prolapse.

OBJECTIVE: The treatment of mitral valve prolapse involves two distinct repair techniques: chordal replacement (Neochordae technique) and leaflet resection (Resection technique). However, there is still a debate in the literature about which is the optimal one. In this context, we performed an image-based computational fluid dynamic study to evaluate blood dynamics in the two surgical techniques. METHODS: We considered a healthy subject (H) and two patients (N and R) who underwent surgery for prolapse of the posterior leaflet and were operated with the Neochordae and Resection technique, respectively. Computational Fluid Dynamics (CFD) was employed with prescribed motion of the entire left heart coming from cine-MRI images, with a Large Eddy Simulation model to describe the transition to turbulence and a resistive method for managing valve dynamics. We created three different virtual scenarios where the operated mitral valves were inserted in the same left heart geometry of the healthy subject to study the differences attributed only to the two techniques. RESULTS: We compared the three scenarios by quantitatively analyzing ventricular velocity patterns and pressures, transition to turbulence, and the ventricle ability to prevent thrombi formation. From these results, we found that the operative techniques affected the ventricular blood dynamics in different ways, with variations attributed to the reduced mobility of the Resection posterior leaflet. Specifically, the Resection technique resulted in turbulent forces, related with the risk of hemolysis formation, up to 640 Pa, while the other two scenarios exhibited a maximum of 240 Pa. Moreover, in correspondence of the ventricular apex, the Resection technique reduced the areas with low velocity to 15%, whereas the healthy case and the Neochordae case maintained these areas at 30 and 48%, respectively. Our findings suggest that the Neochordae technique developed a more physiological flow with respect to the Resection technique. CONCLUSION: Resection technique gives rise to a different direction of the mitral jet during diastole increasing the ability to washout the ventricular apex preventing from thrombi formation, but at the same time it promotes turbulence formation that is associated with ventricular effort and risk of hemolysis.

Modeling and Control of an MR-Safe Pneumatic Radial Inflow Motor and Encoder (PRIME).

Magnetic resonance (MR) conditional actuators and encoders are the key components for MR-guided robotic systems. In this article, we present the modeling and control of our MR-safe pneumatic radial inflow motor and encoder. A comprehensive model is developed that considers the primary dynamic elements of the system, including: 1) motor dynamics, 2) pneumatic transmission line dynamics, and 3) valve dynamics. After model validation, we present a simplified third order model that facilitates design of a first order sliding mode controller (TO-SMC). Finally, the motor hardware is tested in a 7T MRI. No image distortion or artifacts were observed. We posit the MR-safe motor and dynamic model will lower the entry barriers for researchers interested in MR-guided robots and promote wider adoption of MR-guided robotic systems.

Chattering analysis of an electro-hydraulic backstepping velocity controller

This paper focuses on the chattering analysis in a backstepping controller used to drive an electro-hydraulic servo system. The chattering phenomenon, well known in sliding mode control, strongly reduces operating performance while causing premature wear of the system. Four cases are studied to highlight the factors influencing the chattering in the backstepping control. In the first case, the effect of the unmodeled fast servo valve dynamics is analysed by comparing a reduced-order backstepping controller with a full-order controller. The second case analyses the sensitivity to the tuning gains of the backstepping controller. The third case emphasises the influence of the parameter of sign function approximation. The last case analyses the sensitivity of the parameter of the time derivative of the virtual controls. The simulation results in the Matlab/Simulink show that the chattering is mitigated by an appropriate gains tuning but above all an appropriate calculation of the derivatives of the virtual controls, particularly for high-order systems.

A novel CFD-ANN approach for plunger valve optimization: Cost-effective performance enhancement

This paper introduces a novel computational fluid dynamics-artificial neural network (CFD-ANN) approach that has been devised to enhance the efficiency of plunger valves. The primary emphasis of this research is to achieve an optimal equilibrium between hydraulic flow and geometric configuration. This study is a novel contribution to the field as it explores the flow dynamics of plunger valves using Computational Fluid Dynamics (CFD) and proposes a unique methodology by incorporating Machine Learning (ML) for performance forecasting. An artificial neural network (ANN) architecture was developed using a thorough comprehension of flow physics and the impact of geometric parameters acquired through computational fluid dynamics (CFD). Using optimization, the primary aspects of the Artificial Neural Network (ANN), including the learning algorithm and the number of hidden layers, have been modified. This refinement has resulted in the development of an architecture exhibiting a remarkably high R2 value of 0.987. This architectural design was employed to optimize the plunger valve. By utilizing Artificial Neural Networks (ANN), a comprehensive analysis comprising 1000 distinct configurations was effectively performed, resulting in a significant reduction in time expenditure compared to relying on Computational Fluid Dynamics (CFD). The result was a refined arrangement that achieved maximum head loss, subsequently verified using computational fluid dynamics (CFD) simulations, resulting in a minimal discrepancy of 2.66%. The efficacy of artificial neural networks (ANN) becomes apparent due to their notable cost-efficiency, along with their capacity to produce outcomes that are arduous and expensive to get through conventional optimization research utilizing computational fluid dynamics (CFD).

Experimental study on quantitative characterization of cavitation internal structure based on the distribution of void fraction in pressure relief valve

Accurately quantify the complex structure of cavitation in pressure relief valve by experiment remains a challenging task. In this research, a quantitative method for assessing the vapor volume fraction in cavitation images by void fraction experimentally is proposed, this method is less affected by environmental interference and could achieve rapid and accurate characterization of cavitation. The results show that void fraction effectively represents changes in vapor volume fraction under different conditions. The influence of the grid division numbers on the vapor volume fraction is investigated, the optimal number of grid division is 93 in X direction, with a misjudgment number of 130 and a misjudgment rate of 1.62 %. The effects of grid numbers on vapor volume fraction under different cavitation image pixels is also discussed, the optimal number of grid division is 112 in flow direction, with a misjudgment number of 144 and a misjudgment rate of 1.21 %. Through processing the vapor volume fraction image using the Proper Orthogonal Decomposition (POD) method under different cavitation numbers, the results show that the cavitation number has an important influence on the proportion of re-entrant jet area and cavitation collapse area, when the cavitation number decreases to 0.047, the proportion of re-entrant jet area and cavitation collapse area achieve the maximum that 6.41 % and 8.68 %, respectively. Such quantitative analysis of the cavitation degrees under various working conditions can contribute to a better understanding of the impact of cavitation on valve dynamics mechanisms.

Exploring the dynamics of passive isolation flap valves in dust explosion mitigation: a model-based approach and its implications

Passive isolation flap valves are relatively simple devices widely used in the process industries. However, as with any explosion mitigation technique, they work only within well-defined conditions, and the underlying physics makes any prediction difficult. The current paper presents new methods and findings, which rely on experiments on passive flap valves tested on 0.7 to 10 m3 vessels with 100 to 800 mm pipes. This study considers the simple configuration of a flap valve connected to a vented vessel-straight duct arrangement. The explosion in the vessel triggers the closure of the initially opened flap valve and should be effective within a short delay to prevent the flame from passing. The explosion in the vessel drives both the fluid flow in the pipes and the flap valve closing duration. The sudden closing of the pipe induces a complex fluid flow, including significant pressure and velocity fluctuations around the flap valve and a backflow towards the vessel. The commonly used empirical laws, such as those displayed in the EN standards on dust explosions, do not account for these fluid-structure interactions. A hybrid code has been developed to describe the fluid flow throughout the assembly. This code combines an integral model for the vessel and flap explosions, a 1D Eulerian method relying on a MacCormack scheme for the pipes, and a damped pendulum model for the flap solved using an RK4 scheme. The model results compare satisfyingly well with experimental results. The discussion focuses on analysing the problem's physics, from which design engineering rules are derived.

Research on the characteristics of two-phase flow-induced noise in the cavitation dynamics of electronic expansion valves

Electronic expansion valves are widely used in refrigeration systems. However, the two-phase flow-induced noise is often produced during operation. In this paper, the two-phase flow-induced noise characteristics of electronic expansion valves are investigated by means of a combination of numerical calculations and experimental studies. The numerical results show that the noise distribution in the flow field is closely related to the valve opening. As the valve opening increases, the noise in the flow field begins to develop in the downstream region. The experimental results showed a gradual increase in the refrigerant flow rate of the experimental system as the valve opening was increased from 60 to 200 pulses (tested at 10-pulse intervals). The flow-induced noise increases first and then decreases and then increases. With the increase in valve opening, the cavitation phenomenon after valve throttling becomes more and more serious. By processing the noise signal, it is found that the flow-induced noise is distributed in wide frequency. When the valve opening is 60–100 pulse, the noise is mainly concentrated in 10–20 kHz. When the valve opening is 110–150 pulses, the noise concentrated in the high band gradually spreads to the low band. When the valve opening is 160–200 pulses, the noise at low frequency and high frequency increases significantly with the increase in valve opening. After adding a groove structure on the valve core, the noise of the electronic expansion valve decreased by 1.75 dB.

A patient with Tuberculous para-valvular leak and tuberculous hepatic abscesses treated conservatively with anti-tuberculous medication without the need for surgical intervention. “Case report”

Introduction: We report a case of a young lady with rheumatic heart disease who underwent mechanical prosthetic mitral valve replacement and tricuspid valve repair. The case was complicated after one year by multi system tuberculous abscesses, para-valvular leak and hemolytic anemia. Case summary: The case started one year following mechanical prosthetic mitral valve replacement, and after contact with a tuberculous patient. The lady developed, sterile pyuria, two tuberculous hepatic abscesses, and a big pelvic tuberculous abscess. She first needed percutaneous drainage for the pelvic abscess followed by laparotomy and surgical drainage after recurrence. The case was complicated by Para-valvular leak in the prosthetic mitral valve detected by Transoesophageal echocardiography as well as refractory hemolytic anemia needing multiple transfusions. She required six months of anti-tuberculous therapy for the hemolysis to stop. Treatment continued for a total of one year of anti-tuberculous therapy. The patient restored normal valve dynamics and hematological parameters without the need for surgical intervention for the para-valvular leak. Conclusion: We report this case to show that small tuberculous para-valvular leak and hemolytic anemia as well as tuberculous hepatic abscesses can be treated medically as an alternative option to the well-known and recommended surgical indication. We also confirm delayed healing of the abdominal surgical wound due to tuberculosis.

Virtual Model Development of the Load Application System of a Wind Turbine Nacelle Test Bench for Hybrid Test Applications

Abstract The existing nacelle testing methods require continuous improvements to satisfy the ever-increasing demands for testing modern wind turbines. One way to achieve this goal is to use advanced simulation techniques to undertake hybrid testing, in which experiments and simulations are combined to push the boundaries of nacelle testing even further. To do so requires the development of a virtual model of the test bench featuring the true test bench dynamics and functionalities. This contribution presents the development of a virtual model of the complete nontorque load application system of a nacelle test bench at Fraunhofer IWES. The model development methodology is explained and the impact of different levels of modeling depth of the hydraulic system model is investigated. It is concluded that modeling of friction and valve dynamics is necessary as they have significant influence on the generated loads. These findings can help in the development of virtual models of nacelle test benches and pave the way for performing hybrid testing for wind turbine nacelles.

Impact of Multi-Grade Localized Calcifications on Aortic Valve Dynamics under Helical Inflow: A Comparative Hemodynamic Study

This study investigates the hemodynamic impacts of localized aortic valve calcification, utilizing immersed boundary-finite element (IBFE) method simulations with realistic inflow patterns of uniform and helical blood flow from the left ventricular outflow tract (LVOT). We modeled the aortic valve leaflets with varying grades of calcification, assessing their influence on valve performance, including transvalvular hemodynamics, wall shear stress (WSS) indices, and vortical structures. The findings highlighted that calcification significantly restricts leaflet motion, diminishes the orifice area, disrupts flow efficiency, and consequently increases the left ventricular workload. Advanced calcification resulted in elevated WSS, especially at the leaflet tips, which indicates a heightened risk of endothelial damage and further calcification. Asymmetrical calcifications redirect flow towards the ascending aorta wall, potentially inducing structural damage and increased stress on the remaining healthy leaflets. Calcification was also found to alter the naturally occurring helical blood flow patterns, affecting the system’s fluid transport efficiency and possibly contributing to cardiovascular disease progression. The study revealed a significant alteration in vortex formation, with calcification causing distorted and complex vortex structures, which may influence the dynamics of blood flow and valve function. These insights into the hemodynamic changes induced by calcification contribute to a better understanding of the progression of aortic valve diseases and could inform more effective diagnostic and treatment strategies.

Fluid–structure interaction modeling of bi-leaflet mechanical heart valves using smoothed particle hydrodynamics

Heart valves are essential for maintaining unidirectional blood flow, and their failure can severely affect cardiac functions. The use of artificial heart valves as replacement has proven to be a reliable and effective solution. Computational fluid dynamics has emerged as a powerful numerical tool for investigating the design, performance, and malfunctioning of mechanical heart valves without the need for invasive procedures. In this study, we employed smoothed particle hydrodynamics (SPH) in an open-source code “DualSPHysics,” to study the hemodynamics of a bi-leaflet mechanical heart valve (BMHV). The proposed SPH method was validated against the traditional finite volume method and experimental data, highlighting its suitability for simulating the heart valve function. The Lagrangian description of motion in SPH is particularly advantageous for fluid–structure interaction (FSI), making it well-suited for accurately modeling the heart valve dynamics. Furthermore, the SPH/FSI technique was applied to investigate the hemodynamic abnormalities associated with BMHV dysfunction. This work represents the first attempt to use SPH to model flow through a realistic BMHV by incorporating FSI. The normal and altered flow behavior and the movement dynamics of the BMHV under various blockage scenarios have also been investigated along with the potential risks of the blocked mechanical valve. The findings demonstrate that this SPH/FSI approach provides a unique, effective, and valuable tool for accurately capturing the transient hemodynamic behavior of bi-leaflet heart valves and its versatility enables the application to more complex patient-specific issues related to cardiovascular diseases.

Numerical investigation of calcification effects on aortic valve motions and ambient flow characteristics

The pathogenesis and progression of calcific aortic stenosis pose a significant challenge in medical science due to the intricate nature of blood fluid dynamics. To better understand this crucial phenomenon, this study investigates the physiological behaviors of aortic valves with varying degrees of lesions and ambient flow conditions using an in-house CFD solver, CgLES-Y code. The code is validated by simulating two-dimensional valve opening and closure, followed by the extension to three-dimensional symmetrically simplified valve dynamics. The simulation results exhibit great agreement with other numerical, experimental and clinical data. Patient-specific models of the aortic root and inner valve geometries are developed based on CT images. Analysis of fluid dynamics traits, configuration properties and leaflet stress is performed for both normal and calcified aortic valves during the systolic and diastolic periods. The study further examines the impact of calcium deposition on abnormal flow fields and leaflet motion, which indicates that calcium deposition increases the tensional burden on healthy leaflets, therefore, the microcosmic increase in valve modulus leads to global damage extending from the root to the tip, whereas macroscopic calcification primarily induces damage in the vicinity of the calcium compound. Additionally, the generation of additional vortices on the valve surface and sinus lumen heightens the likelihood of calcium accumulation.