Pub Date : 2024-10-28DOI: 10.1016/j.flowmeasinst.2024.102729
Vinícius Diniz Ferrer Santana , Rogério Esteves Salustiano , Rafael de Oliveira Tiezzi
Environmental disasters increase along with disorganized urban growth and irresponsible exploitation of natural resources. The recurrence of hydrological disasters in the municipality of Poços de Caldas (Minas Gerais, Brazil), combined with the geomorphological specificities of the region, result in a demand for an in-depth analysis related to intense precipitation, considering its characteristics and consequences. This study presents a comparative analysis between a linigraph and a laser sensor for fluviometric measurement, pointing out the main differences, similarities, advantages and disadvantages of both systems. The values obtained by the low-cost LIDAR sensor were in agreement with those achieved using the linigraph, which is more expensive, thus demonstrating that the laser sensor can also replace it due to both installation and usage advantages. The laser sensor showed an accuracy of ±0.05 m relative to a metric physical scale, which is considered suitable for applications involving water level measurements in water bodies.
{"title":"Development and calibration of a low-cost LIDAR sensor for water level measurements","authors":"Vinícius Diniz Ferrer Santana , Rogério Esteves Salustiano , Rafael de Oliveira Tiezzi","doi":"10.1016/j.flowmeasinst.2024.102729","DOIUrl":"10.1016/j.flowmeasinst.2024.102729","url":null,"abstract":"<div><div>Environmental disasters increase along with disorganized urban growth and irresponsible exploitation of natural resources. The recurrence of hydrological disasters in the municipality of Poços de Caldas (Minas Gerais, Brazil), combined with the geomorphological specificities of the region, result in a demand for an in-depth analysis related to intense precipitation, considering its characteristics and consequences. This study presents a comparative analysis between a linigraph and a laser sensor for fluviometric measurement, pointing out the main differences, similarities, advantages and disadvantages of both systems. The values obtained by the low-cost LIDAR sensor were in agreement with those achieved using the linigraph, which is more expensive, thus demonstrating that the laser sensor can also replace it due to both installation and usage advantages. The laser sensor showed an accuracy of ±0.05 m relative to a metric physical scale, which is considered suitable for applications involving water level measurements in water bodies.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102729"},"PeriodicalIF":2.3,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142560636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-24DOI: 10.1016/j.flowmeasinst.2024.102726
Meisheng Yang , Kun Lian , Shuang Luo , Chixiang Yu
The pilot-operated electro-hydraulic proportional directional valve is widely used in complex and precision engineering fields. Its operational stability and reliability determine the overall performance of the hydraulic system. During the working process of the pilot-operated electro-hydraulic proportional directional valve, the spool is deformed due to the influence of pressure and temperature, resulting in problems such as clamping or stagnation. In order to solve this problem, this study uses the fluid-solid-thermal coupling simulation method to analyze the flow field characteristics and thermal deformation of the spool with different structural throttling grooves, and optimizes the U-shaped throttling groove structure. The results indicate that as the valve opening increases, the front section of the throttling groove becomes the primary region where the maximum radial deformation of the spool occurs. In this paper, the steady-state flow force of the valve core is taken as the measurement standard, the constraint range of the structural parameters is determined, and the radial thermal deformation is included in the optimization analysis of the structural size. It's verified that the optimized flow characteristics are improved by about 32 % compared with that before optimization, and the maximum steady-state flow force after considering thermal deformation is reduced by about 4N compared with that before optimization. This provides an important design basis and reference for the structural design and optimization of the pilot electro-hydraulic proportional directional valve.
先导式电液比例换向阀广泛应用于复杂和精密工程领域。其工作稳定性和可靠性决定了液压系统的整体性能。先导式电液比例换向阀在工作过程中，由于受到压力和温度的影响，阀芯会产生变形，从而导致夹紧或卡滞等问题。为解决这一问题，本研究采用流固热耦合仿真方法，分析了不同结构节流槽的阀芯流场特性和热变形情况，并对 U 型节流槽结构进行了优化。结果表明，随着阀门开度的增大，节流槽前段成为阀芯径向变形最大的主要区域。本文以阀芯的稳态流力为测量标准，确定了结构参数的约束范围，并将径向热变形纳入结构尺寸的优化分析中。结果表明，优化后的流量特性比优化前提高了约 32%，考虑热变形后的最大稳态流量力比优化前降低了约 4N。这为先导电液比例换向阀的结构设计和优化提供了重要的设计依据和参考。
{"title":"Simulation analysis and optimization of pilot type electro-hydraulic proportional directional valve based on multi field coupling","authors":"Meisheng Yang , Kun Lian , Shuang Luo , Chixiang Yu","doi":"10.1016/j.flowmeasinst.2024.102726","DOIUrl":"10.1016/j.flowmeasinst.2024.102726","url":null,"abstract":"<div><div>The pilot-operated electro-hydraulic proportional directional valve is widely used in complex and precision engineering fields. Its operational stability and reliability determine the overall performance of the hydraulic system. During the working process of the pilot-operated electro-hydraulic proportional directional valve, the spool is deformed due to the influence of pressure and temperature, resulting in problems such as clamping or stagnation. In order to solve this problem, this study uses the fluid-solid-thermal coupling simulation method to analyze the flow field characteristics and thermal deformation of the spool with different structural throttling grooves, and optimizes the U-shaped throttling groove structure. The results indicate that as the valve opening increases, the front section of the throttling groove becomes the primary region where the maximum radial deformation of the spool occurs. In this paper, the steady-state flow force of the valve core is taken as the measurement standard, the constraint range of the structural parameters is determined, and the radial thermal deformation is included in the optimization analysis of the structural size. It's verified that the optimized flow characteristics are improved by about 32 % compared with that before optimization, and the maximum steady-state flow force after considering thermal deformation is reduced by about 4N compared with that before optimization. This provides an important design basis and reference for the structural design and optimization of the pilot electro-hydraulic proportional directional valve.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102726"},"PeriodicalIF":2.3,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-23DOI: 10.1016/j.flowmeasinst.2024.102725
Xinliang Yang , Yanjun Lü , Le Xu , Yushan Ma , Ruibo Chen , Xiaowei Zhao
The tri-eccentric butterfly valve is widely utilized in the petrochemical, nuclear, and metallurgy industries due to its robust sealing performance and great pressure resistance. When the local static pressure is lower than the saturation vapor pressure, the fluid phase is transformed into vapor, and cavitation occurs. Cavitation intensifies and the bubbles generated by cavitation severely hinder the flow when the inlet pressure remains constant and the outlet pressure further decreases. This phenomenon is known as choked flow. Choked flow is a derivative phenomenon of cavitation, which seriously threatens the lifetime of valves and the safety of the operation system. In this paper, a multiphase flow of the tri-eccentric butterfly valve is modeled to investigate the choked flow characteristics. The numerical results based on the proposed model are in good agreement with the experiments. The effect of the pressure drop on the mass flow rate and flow coefficient is studied and the liquid pressure recovery factor of the tri-eccentric butterfly is determined at the certain valve opening degree based on the Schnerr and Sauer cavitation model. The relationship between the pressure ratio and choked flow is studied by pressure and velocity contours. The susceptible erosion locations and primary causes of erosion for the tri-eccentric butterfly valve at the certain valve opening degree are investigated. By comparison of the distribution of the vapor volume fraction and vortex structures, the spatial correlation between vortex and choked flow is revealed. Meanwhile, the effect of the pressure ratios on the average vapor volume fraction at 70 % and 100 % valve opening degrees is studied. The evolution of choked flow in the tri-eccentric butterfly is revealed and the cause of choking is pointed out.
{"title":"Numerical investigation on cavitation erosion and evolution of choked flow in a tri-eccentric butterfly valve","authors":"Xinliang Yang , Yanjun Lü , Le Xu , Yushan Ma , Ruibo Chen , Xiaowei Zhao","doi":"10.1016/j.flowmeasinst.2024.102725","DOIUrl":"10.1016/j.flowmeasinst.2024.102725","url":null,"abstract":"<div><div>The tri-eccentric butterfly valve is widely utilized in the petrochemical, nuclear, and metallurgy industries due to its robust sealing performance and great pressure resistance. When the local static pressure is lower than the saturation vapor pressure, the fluid phase is transformed into vapor, and cavitation occurs. Cavitation intensifies and the bubbles generated by cavitation severely hinder the flow when the inlet pressure remains constant and the outlet pressure further decreases. This phenomenon is known as choked flow. Choked flow is a derivative phenomenon of cavitation, which seriously threatens the lifetime of valves and the safety of the operation system. In this paper, a multiphase flow of the tri-eccentric butterfly valve is modeled to investigate the choked flow characteristics. The numerical results based on the proposed model are in good agreement with the experiments. The effect of the pressure drop on the mass flow rate and flow coefficient is studied and the liquid pressure recovery factor of the tri-eccentric butterfly is determined at the certain valve opening degree based on the Schnerr and Sauer cavitation model. The relationship between the pressure ratio and choked flow is studied by pressure and velocity contours. The susceptible erosion locations and primary causes of erosion for the tri-eccentric butterfly valve at the certain valve opening degree are investigated. By comparison of the distribution of the vapor volume fraction and vortex structures, the spatial correlation between vortex and choked flow is revealed. Meanwhile, the effect of the pressure ratios on the average vapor volume fraction at 70 % and 100 % valve opening degrees is studied. The evolution of choked flow in the tri-eccentric butterfly is revealed and the cause of choking is pointed out.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102725"},"PeriodicalIF":2.3,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-21DOI: 10.1016/j.flowmeasinst.2024.102709
R. Mitra, M. Sieger, V. Galindo, T. Vogt, F. Stefani, S. Eckert, T. Wondrak
Contactless Inductive Flow Tomography (CIFT) is a flow measurement technique that is able to reconstruct the time-dependent three-dimensional velocity field in electrically conducting fluids, e.g., liquid metals, from magnetic field measurements. The paper describes the design of a specific CIFT measurement set-up for flow studies in liquid metal Rayleigh–Bénard convection (RBC) in a large cylinder of aspect ratio (diameter/height) of filled with the ternary alloy GaInSn as model fluid. An optimized configuration for the CIFT excitation system and magnetic field sensor layout under consideration of the specific requirements for the application in turbulent RBC is determined by numerical simulations. The new experimental CIFT-RBC system resulting from the design process is constructed and a preliminary experiment at a Rayleigh number of and a Prandtl number of is performed and evaluated.
{"title":"Design of a Contactless Inductive Flow Tomography system for a large Rayleigh–Bénard convection cell with aspect ratio Γ=0.5","authors":"R. Mitra, M. Sieger, V. Galindo, T. Vogt, F. Stefani, S. Eckert, T. Wondrak","doi":"10.1016/j.flowmeasinst.2024.102709","DOIUrl":"10.1016/j.flowmeasinst.2024.102709","url":null,"abstract":"<div><div>Contactless Inductive Flow Tomography (CIFT) is a flow measurement technique that is able to reconstruct the time-dependent three-dimensional velocity field in electrically conducting fluids, e.g., liquid metals, from magnetic field measurements. The paper describes the design of a specific CIFT measurement set-up for flow studies in liquid metal Rayleigh–Bénard convection (RBC) in a large cylinder of aspect ratio (diameter/height) of <span><math><mrow><mi>Γ</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>5</mn></mrow></math></span> filled with the ternary alloy GaInSn as model fluid. An optimized configuration for the CIFT excitation system and magnetic field sensor layout under consideration of the specific requirements for the application in turbulent RBC is determined by numerical simulations. The new experimental CIFT-RBC system resulting from the design process is constructed and a preliminary experiment at a Rayleigh number of <span><math><mrow><mi>R</mi><mi>a</mi><mo>=</mo><mn>2</mn><mo>.</mo><mn>13</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>7</mn></mrow></msup></mrow></math></span> and a Prandtl number of <span><math><mrow><mi>P</mi><mi>r</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>03</mn></mrow></math></span> is performed and evaluated.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102709"},"PeriodicalIF":2.3,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-20DOI: 10.1016/j.flowmeasinst.2024.102722
Fei Xue, Shifang Yuan, Yingnan Shen, Rui Su, Xin Fu, Ning Xu
In the wet process of semiconductor manufacturing, the high reliability and safety of the liquid supply system are crucial. The pulsation of liquid output from bellows pumps can cause pipeline vibrations, leading to reduced system lifespan and reliability, potential component damage, and ultimately decreased process yield. To address this issue, this paper proposes an adaptive damper based on a combination of cone-slide valve regulation, specifically designed to mitigate pulsations in the liquid supply system. By establishing a mathematical model of the damper, we investigated the parameters affecting its pulsation absorption rate and response characteristics, and developed a prototype. Experimental results indicate that increasing the gas chamber volume and reducing the stiffness of the bellows significantly enhance the damper pulsation absorption rate. The effective flow area of the control valve influences the response characteristics of the system. The damper demonstrates excellent pulsation suppression performance with varied system pressure and input flow rates. The proposed design method and damper model are experimentally validated, providing a theoretical foundation and technical support for optimizing liquid supply systems in semiconductor wet processes.
{"title":"Research on adaptive damper based on cone-slide valve combination regulation principle","authors":"Fei Xue, Shifang Yuan, Yingnan Shen, Rui Su, Xin Fu, Ning Xu","doi":"10.1016/j.flowmeasinst.2024.102722","DOIUrl":"10.1016/j.flowmeasinst.2024.102722","url":null,"abstract":"<div><div>In the wet process of semiconductor manufacturing, the high reliability and safety of the liquid supply system are crucial. The pulsation of liquid output from bellows pumps can cause pipeline vibrations, leading to reduced system lifespan and reliability, potential component damage, and ultimately decreased process yield. To address this issue, this paper proposes an adaptive damper based on a combination of cone-slide valve regulation, specifically designed to mitigate pulsations in the liquid supply system. By establishing a mathematical model of the damper, we investigated the parameters affecting its pulsation absorption rate and response characteristics, and developed a prototype. Experimental results indicate that increasing the gas chamber volume and reducing the stiffness of the bellows significantly enhance the damper pulsation absorption rate. The effective flow area of the control valve influences the response characteristics of the system. The damper demonstrates excellent pulsation suppression performance with varied system pressure and input flow rates. The proposed design method and damper model are experimentally validated, providing a theoretical foundation and technical support for optimizing liquid supply systems in semiconductor wet processes.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102722"},"PeriodicalIF":2.3,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-20DOI: 10.1016/j.flowmeasinst.2024.102723
Yong Yang , Zengmeng Zhang , Yunrui Jia , Tingyu Geng , Weiling Xu , Kang Zhang
Many hydraulic tools, like hydraulic cylinders and hydraulic artificial muscle joints are operated by adjusting pressure differences between different zones. Typically, the method employed to change the pressure difference is establishing hydraulic bridges and adjusting liquid resistance. While effective, this method's drawback is complex structures. To address this issue, a water-hydraulic pressure difference control valve, integrating two hydraulic bridges, was designed. The static performances including the output pressure difference, the flow rate and the force acting on the valve core were analyzed using AMESim and computational fluid dynamics simulations. Based on the simulation results, a prototype of voice coil motor direct drive pressure difference control valve was manufactured and the corresponding experiments were carried out. The computational fluid dynamics simulation results show that the internal leakage and the through-flow capacity difference between throttling grooves affect the flow field characteristics of the valve. When the pump pressure is 3 MPa and the valve opening is at the middle position, the internal leakage increases the flow rate from 2.25 L/min to 2.38 L/min, and the through-flow capacity difference reduces the control port pressure from the theoretical analysis of 1.5 MPa–1.41 MPa. Furthermore, combined with the analysis of the external liquid resistance, the AMESim model of the pressure difference control valve is modified. When the pump pressure is 3 MPa, the pressure difference and flow rate average deviations between the modified AMESim model and the experiment are 0.021 MPa and 0.048 L/min. Finally, a rotational angle experiment for a water hydraulic artificial muscle joints showed satisfactory control effects, suggesting the valve's application in controlling hydraulic tools and actuators.
{"title":"Simulation analysis and experimental research on static performance of water-hydraulic pressure difference control valve","authors":"Yong Yang , Zengmeng Zhang , Yunrui Jia , Tingyu Geng , Weiling Xu , Kang Zhang","doi":"10.1016/j.flowmeasinst.2024.102723","DOIUrl":"10.1016/j.flowmeasinst.2024.102723","url":null,"abstract":"<div><div>Many hydraulic tools, like hydraulic cylinders and hydraulic artificial muscle joints are operated by adjusting pressure differences between different zones. Typically, the method employed to change the pressure difference is establishing hydraulic bridges and adjusting liquid resistance. While effective, this method's drawback is complex structures. To address this issue, a water-hydraulic pressure difference control valve, integrating two hydraulic bridges, was designed. The static performances including the output pressure difference, the flow rate and the force acting on the valve core were analyzed using AMESim and computational fluid dynamics simulations. Based on the simulation results, a prototype of voice coil motor direct drive pressure difference control valve was manufactured and the corresponding experiments were carried out. The computational fluid dynamics simulation results show that the internal leakage and the through-flow capacity difference between throttling grooves affect the flow field characteristics of the valve. When the pump pressure is 3 MPa and the valve opening is at the middle position, the internal leakage increases the flow rate from 2.25 L/min to 2.38 L/min, and the through-flow capacity difference reduces the control port pressure from the theoretical analysis of 1.5 MPa–1.41 MPa. Furthermore, combined with the analysis of the external liquid resistance, the AMESim model of the pressure difference control valve is modified. When the pump pressure is 3 MPa, the pressure difference and flow rate average deviations between the modified AMESim model and the experiment are 0.021 MPa and 0.048 L/min. Finally, a rotational angle experiment for a water hydraulic artificial muscle joints showed satisfactory control effects, suggesting the valve's application in controlling hydraulic tools and actuators.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102723"},"PeriodicalIF":2.3,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533087","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
One of the essential challenges of flow measurement using the flume structure is whether the flow is free or submerged. Therefore, determining the free-submerged flow boundary is a vital topic. This study experimentally investigates the modular limit/threshold submergence of two kinds of flumes: trapezoidal throat flume (TraTF) and triangular throat flume (TriTF). To this end, the general form of empirical models of the flumes' modular limit index was presented based on dimensional analysis and incomplete self-similarity theory. Then, a set of experimental data was collected. In the next step, empirical relationships were developed using non-linear multivariate regression. The experimental modeling was done in a channel that was 20 m long, 0.6 m wide, and 0.5 m high. A total of 271 tests were conducted, examining nine flumes with trapezoidal throats and four with triangular throats at various flow rates. The TraTF formula has been developed, with 98 % of its predictions having an error of less than 10 % and an average error of 3 %. For the TriTF formula, 96 % of its predictions have an error of less than 10 %, and the average error is 3.6 %.
{"title":"Development of empirical models for the modular limit of trapezoidal and triangular throat flumes","authors":"Hossein Soltani Kazemi , Mohsen Solimani Babarsad , Mohammad Hossein Pourmmohamadi , Hossein Eslami , Hossein Ghorbanizadeh Kharazi","doi":"10.1016/j.flowmeasinst.2024.102721","DOIUrl":"10.1016/j.flowmeasinst.2024.102721","url":null,"abstract":"<div><div>One of the essential challenges of flow measurement using the flume structure is whether the flow is free or submerged. Therefore, determining the free-submerged flow boundary is a vital topic. This study experimentally investigates the modular limit/threshold submergence of two kinds of flumes: trapezoidal throat flume (TraTF) and triangular throat flume (TriTF). To this end, the general form of empirical models of the flumes' modular limit index was presented based on dimensional analysis and incomplete self-similarity theory. Then, a set of experimental data was collected. In the next step, empirical relationships were developed using non-linear multivariate regression. The experimental modeling was done in a channel that was 20 m long, 0.6 m wide, and 0.5 m high. A total of 271 tests were conducted, examining nine flumes with trapezoidal throats and four with triangular throats at various flow rates. The TraTF formula has been developed, with 98 % of its predictions having an error of less than 10 % and an average error of 3 %. For the TriTF formula, 96 % of its predictions have an error of less than 10 %, and the average error is 3.6 %.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102721"},"PeriodicalIF":2.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-18DOI: 10.1016/j.flowmeasinst.2024.102720
Yongping Liu , Linyue Wu , Changbin Dong
As a basic component of the non-circular gear hydraulic motor (NGHM), the non-circular planetary gear train (NPGT) offers a number of advantages, including low velocity, high output torque and compact design. Two different types of NPGT pitch curves have been designed using the 4–6 type of NGHM as an example. Aiming at two kinds of pitch curves, the contact ratio solution methods for the planetary gear meshing respectively with the sun gear and the inner gear ring are proposed. A comparative analysis of an integrated pitch curve design and a segmented pitch curve design is conducted to evaluate the effects of varying addendum coefficient (AC) and tool tooth profile angle (TTPA) on the contact ratio. Furthermore, the influence of load, velocity, and contact ratio on the dynamic characteristics (DC) of the NPGT with a segmented pitch curve is investigated through dynamic simulation. The results show that AC and TTPA significantly affect the contact ratio, with an increase in contact ratio observed as TTPA decreases and AC increases. Additionally, the load has a notable impact on the dynamic meshing force and its fluctuation. A higher contact ratio is associated with greater transmission stability in the gear train. This study provides a theoretical foundation for the design and optimization of NGHMs, and expands the potential application of contact ratio effects on NPGTs in this field.
{"title":"Investigation of contact ratio and dynamic characteristics of non-circular planetary gear train in hydraulic motor","authors":"Yongping Liu , Linyue Wu , Changbin Dong","doi":"10.1016/j.flowmeasinst.2024.102720","DOIUrl":"10.1016/j.flowmeasinst.2024.102720","url":null,"abstract":"<div><div>As a basic component of the non-circular gear hydraulic motor (NGHM), the non-circular planetary gear train (NPGT) offers a number of advantages, including low velocity, high output torque and compact design. Two different types of NPGT pitch curves have been designed using the 4–6 type of NGHM as an example. Aiming at two kinds of pitch curves, the contact ratio solution methods for the planetary gear meshing respectively with the sun gear and the inner gear ring are proposed. A comparative analysis of an integrated pitch curve design and a segmented pitch curve design is conducted to evaluate the effects of varying addendum coefficient (AC) and tool tooth profile angle (TTPA) on the contact ratio. Furthermore, the influence of load, velocity, and contact ratio on the dynamic characteristics (DC) of the NPGT with a segmented pitch curve is investigated through dynamic simulation. The results show that AC and TTPA significantly affect the contact ratio, with an increase in contact ratio observed as TTPA decreases and AC increases. Additionally, the load has a notable impact on the dynamic meshing force and its fluctuation. A higher contact ratio is associated with greater transmission stability in the gear train. This study provides a theoretical foundation for the design and optimization of NGHMs, and expands the potential application of contact ratio effects on NPGTs in this field.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102720"},"PeriodicalIF":2.3,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.flowmeasinst.2024.102712
Mumtaz Hussain Qureshi , Abdul Qadir , Wei-Hsin Tien
In this study, a novel streak direction-resolving algorithm is introduced to determine the direction of the flow field for a single image frame with multiple streaks. The streak direction was resolved by varying its intensity from 100 % to 50 % of the total intensity of the streak image. This technique was applied to two main types of flows parallel and Hill's vortex flows, parallel flows were divided into further two types constant velocity parallel flow and accelerating parallel flow. The purpose of using different types of flows was to test the robustness of the algorithm with easy and complex flows. The performance of the algorithm was checked by the angular deviation between the true and least-square fitted velocity vectors. The number of correct synthetic streak directions was measured with the success rate in percentage. A high success rate means low angular deviation and a high number of velocity vectors with correct direction was obtained. In this research, four different types of image formats were considered DP (double precision), 16-bit (without noise), 16-bit (1.0 % noise), 16-bit (5.0 % noise), and 8-bit (without noise) and the best results were obtained for DP and 16-bit image formats. The results of the parallel flows indicated a 100 % streak direction success rate, Hill's vortex was a type of complex flow therefore, the algorithm hard to resolve some streak directions due to very low velocities (less than 0.1 px (pixel)/interval) and very high-velocity gradients (greater than 52 px/interval). The observation shows that Hill's vortex synthetic streak images were resolved with a success rate of 92.76 % which means that the majority of the synthetic streaks were resolved. Experimental analysis was also done by using the PDMS microchannel setup. Intensity variation streaks were recorded with long camera exposure time and for maintaining the intensity variation, as the LED switched on maximum illumination was started, and continuous decrement in illumination was set by switching off at 50 % of the total illumination intensity. The best results were achieved with a 94 % success rate. Therefore, the proposed novel approach can be used with less expensive hardware for image processing with a single image frame and is useful for multiple applications.
{"title":"A novel technique to resolve directional ambiguity for Particle Streak Velocimetry","authors":"Mumtaz Hussain Qureshi , Abdul Qadir , Wei-Hsin Tien","doi":"10.1016/j.flowmeasinst.2024.102712","DOIUrl":"10.1016/j.flowmeasinst.2024.102712","url":null,"abstract":"<div><div>In this study, a novel streak direction-resolving algorithm is introduced to determine the direction of the flow field for a single image frame with multiple streaks. The streak direction was resolved by varying its intensity from 100 % to 50 % of the total intensity of the streak image. This technique was applied to two main types of flows parallel and Hill's vortex flows, parallel flows were divided into further two types constant velocity parallel flow and accelerating parallel flow. The purpose of using different types of flows was to test the robustness of the algorithm with easy and complex flows. The performance of the algorithm was checked by the angular deviation between the true and least-square fitted velocity vectors. The number of correct synthetic streak directions was measured with the success rate in percentage. A high success rate means low angular deviation and a high number of velocity vectors with correct direction was obtained. In this research, four different types of image formats were considered DP (double precision), 16-bit (without noise), 16-bit (1.0 % noise), 16-bit (5.0 % noise), and 8-bit (without noise) and the best results were obtained for DP and 16-bit image formats. The results of the parallel flows indicated a 100 % streak direction success rate, Hill's vortex was a type of complex flow therefore, the algorithm hard to resolve some streak directions due to very low velocities (less than 0.1 px (pixel)/interval) and very high-velocity gradients (greater than 52 px/interval). The observation shows that Hill's vortex synthetic streak images were resolved with a success rate of 92.76 % which means that the majority of the synthetic streaks were resolved. Experimental analysis was also done by using the PDMS microchannel setup. Intensity variation streaks were recorded with long camera exposure time and for maintaining the intensity variation, as the LED switched on maximum illumination was started, and continuous decrement in illumination was set by switching off at 50 % of the total illumination intensity. The best results were achieved with a 94 % success rate. Therefore, the proposed novel approach can be used with less expensive hardware for image processing with a single image frame and is useful for multiple applications.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102712"},"PeriodicalIF":2.3,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-10-16DOI: 10.1016/j.flowmeasinst.2024.102716
Xianfang Wu , Chen Shao , Minggao Tan , Houlin Liu , Runan Hua , Honggang Li
The impeller in vortex pumps is installed at the side of the volute, which causes the flow instability and vibration. This study employs the Renormalization Group k-epsilon (RNG k-ε) turbulence model to investigate the unsteady flow and excitation characteristics within a vortex pump under various flow rates. The results show that increasing the flow rate reduces the low-pressure area in the vaneless chamber, with flow instability primarily occurring in the middle of the vaneless chamber and intensifying with higher flow rate. Pressure pulsation within the vaneless chamber at nominal flow rate is driven by periodic changes in the vortex structure, occurring at approximately twice the shaft frequency (96Hz). As the impeller rotates, pulsation energy propagates from the vaneless chamber to the tongue and outlet. With increasing flow rates, variations of inlet axial flow velocity cause the rise in pressure pulsation in the vaneless chamber. At high flow rate, pressure pulsation in the vaneless chamber increases tenfold compared to low flow rate. The pressure pulsation at the tongue is significantly smaller than that in the vaneless chamber. The rise in pressure pulsation with increasing flow rates is attributed to the displacement of the circulation flow position towards the tongue.
{"title":"Unsteady flow and excitation characteristics in a vortex pump","authors":"Xianfang Wu , Chen Shao , Minggao Tan , Houlin Liu , Runan Hua , Honggang Li","doi":"10.1016/j.flowmeasinst.2024.102716","DOIUrl":"10.1016/j.flowmeasinst.2024.102716","url":null,"abstract":"<div><div>The impeller in vortex pumps is installed at the side of the volute, which causes the flow instability and vibration. This study employs the Renormalization Group k-epsilon (RNG k-ε) turbulence model to investigate the unsteady flow and excitation characteristics within a vortex pump under various flow rates. The results show that increasing the flow rate reduces the low-pressure area in the vaneless chamber, with flow instability primarily occurring in the middle of the vaneless chamber and intensifying with higher flow rate. Pressure pulsation within the vaneless chamber at nominal flow rate is driven by periodic changes in the vortex structure, occurring at approximately twice the shaft frequency (96Hz). As the impeller rotates, pulsation energy propagates from the vaneless chamber to the tongue and outlet. With increasing flow rates, variations of inlet axial flow velocity cause the rise in pressure pulsation in the vaneless chamber. At high flow rate, pressure pulsation in the vaneless chamber increases tenfold compared to low flow rate. The pressure pulsation at the tongue is significantly smaller than that in the vaneless chamber. The rise in pressure pulsation with increasing flow rates is attributed to the displacement of the circulation flow position towards the tongue.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"100 ","pages":"Article 102716"},"PeriodicalIF":2.3,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142533092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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