Abbas Parsaie, Mahziar BasitNejad, Mohammad Bahrami-Yarahmadi
{"title":"Numerical modeling and discharge coefficient analysis of semi-elliptical sharp-crested weirs","authors":"Abbas Parsaie, Mahziar BasitNejad, Mohammad Bahrami-Yarahmadi","doi":"10.1016/j.flowmeasinst.2025.103035","DOIUrl":"10.1016/j.flowmeasinst.2025.103035","url":null,"abstract":"<div><div>Sharp-crested weirs are commonly used for flow measurement in confined channels and low-velocity hydraulic systems, where the head-discharge relationship (H-Q) and discharge coefficient (Cd) are vital for performance assessment. While deriving the H-Q equation analytically involves integrating the velocity profile across the weir's flow section, complex geometries like semi-elliptical weirs introduce elliptic integrals that need numerical solutions. This study introduces a computational framework using Simpson's numerical integration (implemented in Python via Google Colab) to analyze the H-Q relationship for semi-elliptical sharp-crested weirs (SCSCWs). The calibrated model showed an average deviation of 10.2 % from experimental data, indicating acceptable predictive accuracy. Results indicate Cd values between 1.5 and 2.2 for relative heads (H/P = 0.1–0.8), with orientation-dependent trends: horizontal major axis (HMA) configurations show increasing Cd with head, while vertical major axis (VMA) configurations display decreasing Cd. Two orientation-specific regression models were developed and validated against laboratory data, achieving ∼4 % accuracy for HMA and ∼13 % for VMA.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103035"},"PeriodicalIF":2.7,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917746","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}
Jing Zhang , Weiguo Zhao , Jianhui Bao , Xinlong Li , Huiyun Gao
{"title":"Research on cavitation flow characteristics of rotating disc under different cavitation numbers","authors":"Jing Zhang , Weiguo Zhao , Jianhui Bao , Xinlong Li , Huiyun Gao","doi":"10.1016/j.flowmeasinst.2025.103026","DOIUrl":"10.1016/j.flowmeasinst.2025.103026","url":null,"abstract":"<div><div>Cavitation has always been a research hotspot in the field of fluid machinery. As one of the components of an impeller—the core component of fluid machinery—the hydrodynamic and cavitation characteristics of airfoils are of vital importance to fluid machinery performance. Currently, cavitation flow characteristics around stationary hydrofoils have been extensively studied, but research on rotating hydrofoils remains limited. This paper takes the NACA 0015 airfoil mounted on a rotating disc as a research object. By combining experimental and numerical simulation methods, it investigates the cavitation flow characteristics around the airfoil under different cavitation numbers by varying rotational speed. Meanwhile, based on entropy generation theory, the study analyzes energy loss characteristics in the disc induced by cavitation. Results show that the disc's cavitation number decreases with increasing rotational speed, and cavitation occurs at the airfoil trailing edge under all cavitation numbers, primarily due to wake effects. When the cavitation number <em>σ</em> ≤ 0.55, cavitation emerges on the airfoil suction surface. As the cavitation number decreases, cavitation extends from the leading to trailing edge, intensifying the phenomenon and increasing disc energy loss—largely caused by low-pressure region formation. Studying the rotating disc's cavitation characteristics provides theoretical support for the stable and safe operation of hydraulic machinery.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103026"},"PeriodicalIF":2.7,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917743","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":"Model experimental study on draft vortex characteristics based on motion information analysis","authors":"Min Sheng, Ruhao Dai, Bo Yang","doi":"10.1016/j.flowmeasinst.2025.103037","DOIUrl":"10.1016/j.flowmeasinst.2025.103037","url":null,"abstract":"<div><div>In the model test of hydraulic turbine, it is necessary to observe the vortex to confirm the hydraulic development process and operation stability. In order to record more static and dynamic information at the test conditions, observing and recording method based on tests experience was proposed in this paper. This method differs from existing methods of directly observing and recording the draft vortex, as it can simultaneously extract the motion information of the vortex. The application of this method to a Francis turbine model was carried out on the Toshiba Hydraulic General Test Platform, and the variation laws of vortex flow regime and characteristics under different flow rates were studied. Furthermore, Swirl Number was attempted to use to characterize the information obtained from organizing and recording. The results show that the observation and test information can be supplemented and improved by this method implementation, thus the numerical simulation results in the development process can be verified, and this also have reference significance for the prototype operation.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103037"},"PeriodicalIF":2.7,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144891877","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":"A method for identifying the factors impacting the stability of the pressure difference control component in aero-engine fuel metering unit","authors":"Wenqiang Li, Xin Li, Zhifeng Ye","doi":"10.1016/j.flowmeasinst.2025.103027","DOIUrl":"10.1016/j.flowmeasinst.2025.103027","url":null,"abstract":"<div><div>The pressure difference control component (PDCC) plays a crucial role in maintaining the metering flow stability of the aero-engine fuel metering unit(FMU). To ensure the stability of metering flow, a method for identifying factors impacting the stability of PDCC by analyzing the eigenvalue trajectories is proposed based on Lyapunov’s first method. The high-confidence nonlinear state space model of the PDCC is established, and its linear model is obtained by the Jacobian matrix. The original eigenvalue trajectories are extremely chaotic, which makes it difficult to analyze the stability influence law of design parameters. To address the issue, an eigenvalue classifier is designed according to the principle of minimum distance and position assignment criterion. 6 factors which have a key effect on the stability of PDCC, such as throttling orifice opening area of the pressurized locking valve(PLA), are effectively identified from 28 design parameters by this method. Based on the results, the mechanism of low-frequency pulsations in metering flow at low flowrate during FMU testing is revealed, and the low-frequency oscillation phenomenon at an unstable operating point(with the oscillation frequency of 28 Hz) is eliminated by adjusting the stability-impacting factors. The proposed method mechanistically reveals how design parameters govern PDCC stability, requiring only a state-space model formulation while eliminating complex model conversions. The approach provides direct guidance for stability-oriented PDCC design and actionable solutions for fault handling of metering flow fluctuation, demonstrating strong industrial applicability.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103027"},"PeriodicalIF":2.7,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144931670","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":"A compact non-contact microstrip sensor integrated with lightweight CNN for accurate water–oil mixture purity estimation","authors":"Seyed Maziar Shah‐Ebrahimi, Mohsen Hayati","doi":"10.1016/j.flowmeasinst.2025.103034","DOIUrl":"10.1016/j.flowmeasinst.2025.103034","url":null,"abstract":"<div><div>This study presents a novel non-contact microwave sensing system based on a microstrip antenna array, developed for precise estimation of water content in oil–water mixtures. The system employs two identical narrowband bandpass antennas operating at a resonant frequency of 2.925 GHz, carefully positioned to maintain measurement consistency. A series of oil samples with varying water concentrations (0 %–100 %) were analyzed, and their S<sub>11</sub> and S<sub>21</sub> parameters were recorded. From these, key features including resonance frequency shift (ΔF), return loss (RL), and insertion loss (IL) were extracted and directly fed into a lightweight convolutional neural network (CNN) without additional feature engineering. The model achieved a root mean square error (RMSE) of 1.80, demonstrating strong predictive accuracy. Furthermore, the sensor exhibited a high sensitivity of approximately 13.4 MHz per unit change in relative permittivity (εr), enabling it to detect subtle dielectric differences across the mixture compositions. The proposed method offers a compact, efficient, and scalable solution for real-time, non-invasive purity monitoring, with potential applications in petrochemical processing, oil quality control, and environmental monitoring.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103034"},"PeriodicalIF":2.7,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913025","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":"Multi-channel signal processing method for vortex flowmeter based on parallel filtering","authors":"Jie Chen, Kai Li, Shuxu Wan, Bin Li","doi":"10.1016/j.flowmeasinst.2025.103010","DOIUrl":"10.1016/j.flowmeasinst.2025.103010","url":null,"abstract":"<div><div>The vortex flowmeter holds a significant position in the field of flow measurement, owing to its advantages such as the absence of mechanical moving parts, adaptability to various media, and low pressure loss. The vortex signal detected by piezoelectric elements undergoes a series of amplification, filtering, and other processing steps through analog and digital circuits to achieve accurate flow measurement. To enhance the dynamic response of the vortex flowmeter, a multi-channel parallel signal processing method with a 1/<span><math><msup><mrow><mi>f</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> amplitude–frequency modulation characteristic is proposed. By employing a 1/<span><math><msup><mrow><mi>f</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> filter unit (–40 dB/dec) to lower the minimum detectable flow while keeping the maximum flow unchanged and thus increasing the turndown ratio, the measurement channel is divided into multiple parallel channels. A fast channel selection method is designed to effectively address the issue of slow dynamic response in vortex flowmeter signal processing. Results indicate that the vortex flowmeter, integrated with a four-channel algorithm, achieves a precision level of 0.5 and demonstrates superior dynamic response performance compared to Yokogawa flowmeters.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103010"},"PeriodicalIF":2.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144878324","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}
G. Bharathwaj, Amir Khurshid, S. Venkatavijayan, Ajaya Kumar Pani
{"title":"Industrial process monitoring using support vector data description: A systematic review and application for fault detection in multiphase flow system","authors":"G. Bharathwaj, Amir Khurshid, S. Venkatavijayan, Ajaya Kumar Pani","doi":"10.1016/j.flowmeasinst.2025.103031","DOIUrl":"10.1016/j.flowmeasinst.2025.103031","url":null,"abstract":"<div><div>In the era of Industry 4.0, machine learning based data-driven techniques are increasingly explored for industrial process monitoring. This article presents a review on application of support vector data description (SVDD) for industrial process monitoring followed by the design of SVDD model for fault detection in a multiphase flow system. In the review section, the basic technique, open design issues and a detailed survey on industrial applications are presented. In the application part, PRONTO benchmark multiphase flow dataset, is used to design SVDD model for detection of three faults: air leakage, air blockage and diverted flow. The Gaussian kernel parameter of the SVDD model is determined using particle swarm optimization (PSO) and the starting value for PSO, is obtained from literature provided analytical formula. Simulation of PSO-SVDD models shows promising results for fault detection in multiphase flow system.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103031"},"PeriodicalIF":2.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144924984","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}
Xianglong Liu , Yazhe Liu , Ying Wang , Nan Wang , Huilin Feng , Kun Zhang
{"title":"A hybrid Swin Transformer model for image reconstruction of electrostatic tomography","authors":"Xianglong Liu , Yazhe Liu , Ying Wang , Nan Wang , Huilin Feng , Kun Zhang","doi":"10.1016/j.flowmeasinst.2025.103033","DOIUrl":"10.1016/j.flowmeasinst.2025.103033","url":null,"abstract":"<div><div>The inverse problem of electrostatic tomography (EST) suffers from limited reconstruction accuracy due to its underdetermined and ill-posed properties. Traditional algorithms and CNN models often exhibit significantly reduced performance in noisy environments. To address this challenge, this study proposes a hybrid model that combines ResNet and Swin Transformer. By integrating the residual connections of ResNet with the multi-scale window attention mechanism of Swin Transformer, the proposed model achieves collaborative optimization for local feature extraction and global dependency modeling. The residual structure of ResNet alleviates the gradient vanishing problem and enhances noise robustness. The window attention mechanism of Swin Transformer enhances the model's ability to capture global features of the charge distribution while reducing computational complexity. By compressing the channel dimension via 1D convolution, the model addresses the feature redundancy problem of Swin Transformer's 2D block partitioning, adapting to the 1D boundary signals of EST. Compared with traditional algorithms, the reconstructed image shows clearer edges and fewer artifacts. The robustness of the model is verified by samples with different signal-to-noise ratios. In addition, random samples are used to verify the generalization ability of the model. The imaging results demonstrate that within the range of 0–50 dB noise, with the increase of noise level, the correlation coefficient decreases and the image error increases. The improved model still maintains higher correlation coefficients and lower image errors under different noise levels, demonstrating good anti-noise performance. Compared with other algorithms, the improved model achieves the highest correlation coefficient (0.9652) and the smallest image error (0.1076), indicating the best imaging performance. The research promotes the practical application of deep learning in solving the EST inverse problem.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103033"},"PeriodicalIF":2.7,"publicationDate":"2025-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144878325","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":"Enhancement in heat transfer characteristics, thermal performance and optimized jet height of an ultrasonic pulsating jet of a piezoelectric micro-blower","authors":"Bhola Keshao Rode, Sanjeevi Bharath, V.P. Chandramohan","doi":"10.1016/j.flowmeasinst.2025.103030","DOIUrl":"10.1016/j.flowmeasinst.2025.103030","url":null,"abstract":"<div><div>A micro-blower is a compact device used for cooling compact electronic components through forced convection. The primary objective of this study is to numerically investigate the thermal performance of an ultrasonic pulsating jet produced by a micro-blower impinging on a heated surface and to determine the optimum nozzle-to-surface distance (<em>H</em>) for maximum heat transfer. A commercial 20 × 20 mm<sup>2</sup> micro blower with a nozzle diameter of 0.8 mm and height of 3.65 mm is used for this analysis. The <em>H</em> was varied from 1 to 8 mm and the optimum <em>H</em> for the maximum performance of the system was proposed. The heat transfer coefficient (<em>h</em>), Nusselt number (<em>Nu</em>), temperature of the hot surface (<em>T</em><sub><em>s</em></sub>) and enhancement factor (EF) were estimated. The <em>h</em> profile stabilized within 10 s proving that the micro blower reached its stability within 10 s. The <em>h</em> value was high that is more than 162 W/(m<sup>2</sup>.K) at <em>H</em> = 2, 3 and 4 mm and proved that these heights can be chosen for better performance of micro blower. The maximum EF of 35.12 was achieved at <em>H</em> = 2 mm with an average <em>h</em> of 162.904 W/(m<sup>2</sup>.K) and <em>Nu</em> of 4.446 hence this <em>H</em> can be proposed for better thermal performance. The results were compared to the existing literature and were in good accord. Such analysis was not found for micro-blower jet impingement hence the present study is an innovative approach.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103030"},"PeriodicalIF":2.7,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144864616","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":"Prototype spillway observations: self-aeration on a smooth chute","authors":"H. Chanson","doi":"10.1016/j.flowmeasinst.2025.103019","DOIUrl":"10.1016/j.flowmeasinst.2025.103019","url":null,"abstract":"<div><div>Dams and reservoirs constitute an essential means of water security and flood protection. The hydraulic structure must be equipped with a spillway system to pass safely excess flood waters during natural disasters. To date the literature remains very limited on prototype observations of spillway chute flows. The current contribution presents field observations conducted between 1997 and 2025 at a large dam equipped with a smooth-invert spillway. For all investigated flood events, the overflow consisted of an upstream non-aerated flow region followed by a self-aerated flow region with significant air-water mixing. The location of the onset of free-surface aeration presented some three-dimensional features. Downstream, the air-water flow region exhibited some rapid time variations in air-water surface structures. Long-exposure photography and stacked imaging highlighted the extremely complicated nature of the air-water surface region in the high-Reynolds number flows. The air-water surface was a highly turbulent region corresponding to the outer edge of the boundary layer region, while further self-aeration took place in the hydraulic jump at the downstream end.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 103019"},"PeriodicalIF":2.7,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144893549","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}