Flow Measurement and Instrumentation最新文献

{"title":"Back to basics: On the proper determination of free-surface slope (FSS) in gradually varied open channel flows","authors":"Emma House ,&nbsp;Kyeongdong Kim ,&nbsp;Marian Muste ,&nbsp;Ehab Meselhe ,&nbsp;Ibrahim Demir","doi":"10.1016/j.flowmeasinst.2025.102979","DOIUrl":"10.1016/j.flowmeasinst.2025.102979","url":null,"abstract":"<div><div>This study is a fundamental evaluation of the fluvial wave propagation in river reaches affected by hysteresis, one of the most complex open-channel topics, materialized in loops and lags among hydraulic variables. Hysteresis processes are still understudied as measurements in natural streams for the whole wave propagation duration are hardly available, while the data from existing gaging sites (almost exclusively relying on stage-discharge relationships) can deviate up to 65 % from the actual flows. A better understanding of hysteresis in general and its impact on streamflow monitoring in unsteady flows can be obtained if the free-surface slope (FSS) is determined and analyzed for its variation during wave propagation. Reliable FSS replication in such flows requires a robust understanding of the spatial-temporal sampling constraints. The study addresses the basic, but still weakly resolved, issue of tracing the FSS for waves of different magnitudes and durations. We do so by translating theoretical concepts on oscillatory waves to fluvial counterparts and observing rules for sampling continuous-time signals with discrete-time measurements. The conceptual understanding is verified with numerical simulations and experimental data represented in Eulerian and Lagrangian observation frameworks. We demonstrate that sampling stream stages with spatial and temporal resolutions (expressed in terms of fractions of the wavelength, <em>dx</em>_<em>i</em><em>/λ</em>_<em>R,</em> and duration, <span><math><mrow><msub><mrow><mo>Δ</mo><mi>T</mi></mrow><mi>i</mi></msub><mo>/</mo><msub><mi>T</mi><mi>R</mi></msub></mrow></math></span> for the flood wave to reach its peak) between approximately<span><math><mrow><msub><mrow><mspace></mspace><msub><mrow><mspace></mspace><mn>0.0075</mn><mo>≤</mo><mi>d</mi><mi>x</mi></mrow><mi>i</mi></msub><mo>/</mo><mi>λ</mi></mrow><mi>R</mi></msub><mo>≤</mo><mn>0.01</mn></mrow></math></span> and, 0.004 <span><math><mrow><mo>≤</mo><msub><mrow><mo>Δ</mo><mi>T</mi></mrow><mi>i</mi></msub><mo>/</mo><msub><mi>T</mi><mi>R</mi></msub><mo>≤</mo><mn>0.06</mn></mrow></math></span>, respectively, are required to properly trace FSS for subsequent usage in experimental or numerical simulation contexts.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102979"},"PeriodicalIF":2.3,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322123","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}

{"title":"Experimental investigation of leakage flow measurement and surface morphology in small-scale liquid mechanical seals","authors":"Shaolin Liu,&nbsp;Amine Ben-Abdelwahed,&nbsp;Alain Sommier,&nbsp;David Reungoat,&nbsp;Philippe Darnis","doi":"10.1016/j.flowmeasinst.2025.102957","DOIUrl":"10.1016/j.flowmeasinst.2025.102957","url":null,"abstract":"<div><div>This study presents an experimental investigation into the fluid leakage behavior of small-scale liquid mechanical seals, with a focus on precise leakage flow characterization under controlled conditions. An advanced experimental platform was developed to simulate realistic operating conditions, including varying pressures and rotational speeds, enabling accurate assessment of fluid transport mechanisms in mechanical seals. The investigation involved detailed leakage flow rate measurements and surface roughness characterization for two types of seals: a worn seal (3000 h of industrial use) and a new, unused seal. Leakage flow rates were measured using a volumetric collection method to capture flow variations under controlled pressure (up to 12 bars) and rotational speed conditions (up to 6000 rpm). Non-contact surface roughness analysis was conducted using the AltiSurf 500 profilometer, providing 1D, 2D roughness profiles, and 3D surface reconstructions. Results indicate that the worn seal exhibited a lower average roughness (Ra = 0.08928–0.1397 <span><math><mi>μ</mi></math></span>m) compared to the new seal (Ra = 0.1203–0.2023 <span><math><mi>μ</mi></math></span>m). Despite this smoother surface, kurtosis (Rku) analysis revealed higher peak sharpness in the worn seal (Rku = 13.7611) versus the new seal (Rku = 6.5860), indicating localized surface peaks induced by prolonged operational wear. Leakage flow rate measurements revealed distinct trends. At a constant differential pressure of 4 bars, the worn seal exhibited unstable leakage flow at rotational speeds below 3000 rpm but stabilized at 12.0 mL/h (±0.5 mL/h) above this threshold. Under constant speed conditions (4000 rpm), leakage remained minimal at low pressure differentials (<span><math><mo>&lt;</mo></math></span>1 bar) but increased significantly beyond 5 bars, marking a transition in leakage mechanisms. The new seal exhibited minimal leakage under all conditions, highlighting the strong correlation between surface evolution and leakage characteristics. These findings provide valuable insights into leakage flow measurement techniques and reveal the influence of surface morphology changes on fluid transport in mechanical seals. The results contribute to improved measurement methodologies and provide guidance for optimizing seal design in aerospace applications.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102957"},"PeriodicalIF":2.3,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144280837","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}

{"title":"Research on hydraulic characteristics and discharge calculation methods for top-hinge trapezoidal gates","authors":"Wanshang Meng ,&nbsp;Lin Li ,&nbsp;Wenming Zhang","doi":"10.1016/j.flowmeasinst.2025.102978","DOIUrl":"10.1016/j.flowmeasinst.2025.102978","url":null,"abstract":"<div><div>This study proposes a novel type of flat sluice gate – top-hinge trapezoidal gate, which is suitable for integrated flow measurement and control in canal systems at various levels in irrigation districts or for medium and small-scale water diversion canals. This paper investigates the hydraulic characteristics of the top-hinge trapezoidal gate under free-flow and submerged-flow through both theoretical and experimental methods. A total of 192 groups of free-flow tests and 384 groups of submerged-flow tests were conducted. Based on the experimental data and theoretical analysis, threshold condition formulas were proposed, achieving accuracy rates of 100 % for free flow and 98 % for submerged flow. Discharge equations for the top-hinge trapezoidal gate were established and evaluated. The average relative errors were 2.05 % for free-flow and 2.21 % for submerged-flow when derived from dimensional analysis, and 3.04 % and 3.39 %, respectively, when using the equations derived from the energy conservation method. The dimensional analysis method yielded slightly higher accuracy than the energy conservation method. The research findings provide important theoretical and practical guidance for the application of top-hinge trapezoidal gates.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102978"},"PeriodicalIF":2.3,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144306470","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}

{"title":"Developing the next generation of dual-tip phase-detection probes for air–water flow experiments","authors":"Matthias Kramer","doi":"10.1016/j.flowmeasinst.2025.102949","DOIUrl":"10.1016/j.flowmeasinst.2025.102949","url":null,"abstract":"<div><div>Self-aeration is a fascinating phenomenon that commonly occurs in high Froude-number flows in natural or human made environments. The most common air–water flow measurement instrument to characterise such flows is the intrusive dual-tip phase-detection needle probe, which identifies phase changes around the needle tips due to a change of resistivity (phase-detection conductivity probe) or light refraction (phase-detection fibre optical probe). Phase-detection conductivity probes are typically custom made for research purposes, with current design dating back to the 1980ies. In the present study, the next generation of dual-tip conductivity probes is developed and validated against a state-of-the-art system. The novel probe design comprises two main features, including (1) a printed circuit board of the sensor’s electrodes and (2) a detachable sensor head. These features offer many advantages over the classical needle-type design. For example, the circuit boards can be manufactured with high precision and the sensor head can be easily replaced in case of damage or deterioration. As such, it is anticipated that this relatively cheap and robust design will enable a better repeatability of air–water flow experiments, combined with an enhanced accessibility for the air–water flow research community.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102949"},"PeriodicalIF":2.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144312795","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}

{"title":"Time series identification, classification, and display methods for periodic flow patterns","authors":"Jie Fang ,&nbsp;Rui Li ,&nbsp;Tongyang Zhang ,&nbsp;Jiaxin Zhang ,&nbsp;Kang Zheng ,&nbsp;Jinfan Liu ,&nbsp;Guobiao Cai","doi":"10.1016/j.flowmeasinst.2025.102977","DOIUrl":"10.1016/j.flowmeasinst.2025.102977","url":null,"abstract":"<div><div>In the oxygen turbopump of a LOX/kerosene rocket engine, low-temperature gas-liquid flow and phase change processes occur, representing a typical case of direct contact condensation (DCC). DCC exhibits periodic flow characteristics under certain operating conditions, which are crucial for the normal operation of the rocket engine. This study aims to propose a temporal identification method for flow patterns with periodic characteristics and introduce a new method for displaying flow pattern diagrams to enhance the accuracy of flow pattern identification and description. Through experimental observations, the flow conditions are classified into three main flow patterns: crawling, chugging, and condensation oscillation. This study used You Only Look Once (YOLO) to extract single frame image features and Long Short-Term Memory (LSTM) to extract time series features. After evaluating the confidence of the model, the average accuracy of YOLO and LSTM were 99.33 % and 88.33 %, respectively. Furthermore, the flow pattern diagram proposed in this study effectively integrates temporal information of flow pattern variations with the proportions of different flow patterns. Based on the new flow pattern diagram, the variation rules of flow patterns under low mixing pressure and low mass flow rate were discussed. The trends of flow pattern proportion changes at non-operating points were effectively predicted, and the results align closely with traditional flow pattern diagrams. These findings provide an analytical basis for the mixing process of oxygen-rich gas and liquid oxygen in the inter-pump tubing of LOX/kerosene engines and can support future research.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102977"},"PeriodicalIF":2.3,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144298339","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}

{"title":"Design and development of interdigital capacitive sensor for void fraction measurement","authors":"Amit Pal,&nbsp;B. Vasuki","doi":"10.1016/j.flowmeasinst.2025.102974","DOIUrl":"10.1016/j.flowmeasinst.2025.102974","url":null,"abstract":"<div><div>Two-phase flow is a common occurrence in various industries. Void fraction measurement is a crucial parameter in any two-phase flow because it gives the qualitative and quantitative information about the material in flow channel. This measurement is also important for scheduling maintenance and operation monitoring. In the present research work a novel noninvasive interdigital electrode based capacitive sensor for measurement of void fraction/phase fraction in two phase flow with multiple dimensions and multiple signal conditioning circuits are presented. These sensors are simulated using FEA method and experimentally evaluated on a custom designed experimental setup. The output characteristics of the sensors are analyzed and the capacitance change is in pF range for the whole range of void Fraction i.e. 0 %–100 %.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102974"},"PeriodicalIF":2.3,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144291318","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}

{"title":"Research on non-intrusive particle size measurement method based on acoustic emission technology","authors":"Heming Gao,&nbsp;Bingbing Zhao,&nbsp;Hao Wang","doi":"10.1016/j.flowmeasinst.2025.102975","DOIUrl":"10.1016/j.flowmeasinst.2025.102975","url":null,"abstract":"<div><div>In order to overcome the interference of the waveguide on the flow field in the pipe and its own wear, a novel non-intrusive particle size measurement method is proposed by fusing an acoustic emission sensor and an interdigital-type electrostatic sensor. Firstly, based on the theoretical model of Hertz collision, the mathematical model between particle size and particle velocity, as well as the acoustic emission frequency, is established through theoretical analysis. To address the challenge of obtaining the vertical impact velocity of particles against the pipe wall, a method combining spatial filtering and cross-correlation is introduced to acquire the vertical impact velocity. Then RIME-VMD-FastICA algorithm is proposed for denoising the raw acoustic emission signal. Finally, a pneumatic conveying system is set up, and experiments are conducted on quartz sand particles with five sizes of 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, and 1.2 mm. By analyzing the influence of the spatial filtering velocity, the cross-correlation velocity, and the vertical impact velocity on the particle size measurement results, the feasibility of the non-invasive measurement method is proved, and it is found that the particle size error is the smallest when the vertical impact velocity is used, with the error of less than 10 % for all five particle sizes.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102975"},"PeriodicalIF":2.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242510","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}

{"title":"Numerical and experimental study on delivery flow characteristics for a micro two-dimensional piston pump","authors":"Chuan Ding ,&nbsp;Hanyu Xu ,&nbsp;Yu Huang ,&nbsp;Shuo Liu ,&nbsp;Jian Ruan","doi":"10.1016/j.flowmeasinst.2025.102956","DOIUrl":"10.1016/j.flowmeasinst.2025.102956","url":null,"abstract":"<div><div>The micro two-dimensional piston pump, featuring a unique transmission mechanism and ‘single piston-double displacement chamber’ work mode, is well-suited for high-speed and miniaturized applications. However, due to its small displacement characteristics, flow loss is significantly amplified, which impacts the delivery flow characteristics and introduces ambiguity. This paper focuses on the delivery flow characteristics of the micro two-dimensional piston pump. A computational fluid dynamics model of the pump is established, and its reliability is verified through experiments. The research results show that the micro two-dimensional piston pump has excellent self-priming ability, and the rated maximum speed can reach 9000 r/min at an inlet pressure of 0.3 MPa. When operating at its rated maximum speed, the delivery flow rate is 0.58 L/min at a load pressure of 8 MPa and 0.44 L/min at 28 MPa, exceeding the delivery flow rate of micro axial piston pumps of the same size by more than 1.7 times. The pump adopts the distribution spindle design that increases flow loss due to internal leakage and flow backward under high load pressure, with these losses accounting for 62 % and 33 % of the total flow loss, respectively.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102956"},"PeriodicalIF":2.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242509","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}

{"title":"Unsteady flow discharge measurement over sharp-crested weirs: Insights from a comprehensive experimental dataset","authors":"Salah Kouchakzadeh ,&nbsp;Mohammad R. Nabati ,&nbsp;Ali Haghighi ,&nbsp;Shayan Erfani ,&nbsp;Ava Baradaran-Ketabchi ,&nbsp;Fatemeh Rezaei-Shadehi","doi":"10.1016/j.flowmeasinst.2025.102970","DOIUrl":"10.1016/j.flowmeasinst.2025.102970","url":null,"abstract":"<div><div>Sharp-crested rating curves, traditionally derived from steady-flow conditions, have been used for discharge measurements in both steady and unsteady flow scenarios. Although numerous studies have employed the reservoir drawdown method to calibrate large weirs since the 1960s, data on flow measurements during the passage of hydrographs remain scarce. This article investigates the behavior of unsteady flow over rectangular and triangular sharp-crested weirs under various hydrograph shapes with differing intensities of unsteadiness. Two experimental setups were constructed to collect the data and to observe the performance of these weirs. The collected data were then used to evaluate the accuracy of applying steady-flow rating curves for discharge measurements under unsteady flow conditions. A new index, the Relative Loop Width Index (RLWI), is introduced to quantify the effects of unsteadiness on discharge measurements and the associated errors when utilizing conventional steady flow rating curves. The findings indicate that using steady-flow rating curves in unsteady conditions, which are dominant in field conditions, can result in errors in water volume estimation ranging from +10 % to −20 %. Furthermore, steady-flow rating curves applied to flow measurements during hydrograph passage tend to overestimate peak flows and predict earlier occurrence of peak times. Sensitivity analysis reveals that weir geometry and reservoir capacity significantly influence measurement errors.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102970"},"PeriodicalIF":2.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144242511","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}

{"title":"Exploring the role of filaments in channel flow modification using the immersed boundary lattice Boltzmann method","authors":"Hamid Hassanzadeh Afrouzi ,&nbsp;Saeid Shiri ,&nbsp;MohammadAmir Hasani ,&nbsp;Seyyed Mostafa Seyyedi ,&nbsp;Soheil Salahshour ,&nbsp;Abbasali Abouei Mehrizi ,&nbsp;Xiaohu Chen ,&nbsp;Pouya Pashaie","doi":"10.1016/j.flowmeasinst.2025.102952","DOIUrl":"10.1016/j.flowmeasinst.2025.102952","url":null,"abstract":"<div><div>Manipulating flow at the miniature is a challenging task. This study explores the potential application of elastic filaments to manipulate the flow field in a channel using the immersed boundary-lattice Boltzmann (IB-LBM) method. The channel width and the initial elastic filament length were 4 cm and 1.3 cm, respectively. The presence of the filaments on the channel's center and walls is investigated separately. For the case with two inclined elastic filaments in the middle of the channel, the results showed that the elastic filament deviates from its original state under the influence of the fluid momentum and tends to move in the direction of the flow. The filaments stretch and reach their final position, then start to oscillate under the influence of elasticity and vortexes formed behind them. For the case with 10 filaments distributed over the top and bottom walls with a constant distance between them, the results show that initially the filaments near the entrance cause a disturbance in the flow and induce large vortexes at the end of the channel. However, over time, as the flow reaches a steady state, small vortexes form behind the filaments and, the filaments start to oscillate and the main flow inside the channel remains pretty uniform without obvious vortexes.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102952"},"PeriodicalIF":2.3,"publicationDate":"2025-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144280836","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}