{"title":"Near-field flow features of underexpanded microjets emerging from a rectangular convergent nozzle with a high-aspect-ratio","authors":"Shota Yoshimi, Takahiro Yamashita , Shinichiro Nakao , Yoshiaki Miyazato","doi":"10.1016/j.flowmeasinst.2025.102945","DOIUrl":"10.1016/j.flowmeasinst.2025.102945","url":null,"abstract":"<div><div>Underexpanded microjets emerging from a rectangular convergent nozzle with an aspect ratio of 10 at the exit face are quantitatively visualized via Mach–Zehnder tomography (MZT) with the finite-fringe setting. Multiview interferograms around the central axis of the microjet are taken at a nozzle pressure ratio (NPR) of 4.0. The Reynolds number based upon the height in the minor-axis plane and flow properties at the nozzle exit is 1.74 × 10<sup>4</sup>. Fourier fringe analysis is utilized to extract the phase shifts between the background fringe and deformed fringe patterns. The density fields of the microjets are subsequently reconstructed via the convolution back-projection (CBP) method. Near-field flow features of the microjets are demonstrated with the isopycnic surface as well as the density contour plots in the minor-axis and major-axis planes. In addition, microjets issuing from the nozzle with the same geometry as in the experiment are solved via the Reynolds-averaged Navier–Stokes (RANS) equations with Menter’s shear stress transport (SST) <span><math><mrow><mi>k</mi><mo>−</mo><mi>ω</mi></mrow></math></span> turbulence model for mutual comparison with the experimental results. The streamwise density profiles along the jet centerline as well as the liplines in the minor-axis and major-axis planes are quantitatively compared between the experimental and simulation results. Shock structures and topology showing the streamwise evolution of a shock system in a high-aspect-ratio rectangular microjet are experimentally clarified for the first time with a high spatial resolution of approximately <span><math><mrow><mn>5</mn><mo>.</mo><mn>0</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102945"},"PeriodicalIF":2.3,"publicationDate":"2025-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213244","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}
Qiguang Li , Yulin Zhuang , Xiaokai Liu , Fangmin Xu , Yunbi Zhang , Mingyi Sun
{"title":"A novel method for flow soft measurement of pipeline impact force using Swin-CLG algorithm","authors":"Qiguang Li , Yulin Zhuang , Xiaokai Liu , Fangmin Xu , Yunbi Zhang , Mingyi Sun","doi":"10.1016/j.flowmeasinst.2025.102933","DOIUrl":"10.1016/j.flowmeasinst.2025.102933","url":null,"abstract":"<div><div>In response to the challenge of insufficient accuracy in soft measurement of liquid flow based on impact force in curved pipelines, as identified in previous research (Li et al., 2024), this paper proposes a novel approach that transforms one-dimensional impact force sequence data into a two-dimensional representation. An enhanced Swin-Transformer network architecture is introduced, which integrates a CNN-based feature extraction network with Long Short-Term Memory (LSTM). Furthermore, a Efficient Double Feature layer (EDF layer) and a global attention mechanism (GAM) are incorporated to further refine feature extraction and improve model performance. Experimental results obtained from a fluid impact force and flow collection platform demonstrate that the proposed deep learning model significantly reduces the Mean Absolute Error (MAE) from 7 g to 1.98 g, while increasing the Qualification Rate from 60% to 95%. These findings highlight the substantial improvements in measurement accuracy, underscoring the method’s broad potential and practical value in the field of fluid transport measurement.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102933"},"PeriodicalIF":2.3,"publicationDate":"2025-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203264","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}
Muhammet Ali Karadağ , Pınar Göklüberk , Ali Kibar
{"title":"Experimental and numerical investigation of flow and pressure drop in hydraulic quick connect couplings","authors":"Muhammet Ali Karadağ , Pınar Göklüberk , Ali Kibar","doi":"10.1016/j.flowmeasinst.2025.102960","DOIUrl":"10.1016/j.flowmeasinst.2025.102960","url":null,"abstract":"<div><div>Quick-connect couplings are essential components of hydraulic systems because they offer effective and convenient fluid-line connections. However, conventional ISO 16028 DN 6.3 flat-face valve designs often incur significant energy losses owing to turbulence, flow separation, and abrupt geometric transitions. This study combines experimental and numerical methods to investigate the pressure drops in these couplings, identifying critical energy-loss regions: the socket rear, valve-to-socket junction, and plug rear. Experimental measurements using a centrifugal pump, magnetic flow sensors, and pressure gauges were validated against numerical simulations performed in ANSYS Fluent using the <em>k-ω</em> (SST) turbulence model. The optimized coupling features smoother transitions, reduced contractions, and an innovative two-slot valve configuration, achieving a 2.22 × improvement in the flow coefficient (<em>K</em><sub><em>v</em></sub> = 1.46 vs. 0.68) and a pressure drop reduction from 1.120 bar to 0.244 bar at Re = 28,797. Additionally, peak flow velocity decreased by 51 % (from 16.73 m/s to 8.21 m/s), effectively eliminating cavitation risks. These enhancements comply with ISO 16028 standards while significantly improving the hydraulic efficiency. The bidirectional flow analysis revealed slightly higher pressure losses in the socket-to-plug direction, emphasizing the need for directional optimization. The design delivers lower operational costs, improved reliability, and reduced environmental impacts through energy savings, making it ideal for high-pressure systems and construction equipment. This study demonstrates a sustainable and practical solution, paving the way for future advances in quick-connect coupling designs.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102960"},"PeriodicalIF":2.3,"publicationDate":"2025-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144213243","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":"High-resolution electrical capacitance tomography image reconstruction in oil and gas production processes based on adaptive KAN mechanism","authors":"Chunman Yan, Kai Li","doi":"10.1016/j.flowmeasinst.2025.102948","DOIUrl":"10.1016/j.flowmeasinst.2025.102948","url":null,"abstract":"<div><div>In the oil and gas production process, accurate monitoring of the two-phase flow distribution of petroleum and air within pipelines is crucial for improving transportation efficiency and optimizing production. Electrical Capacitance Tomography (ECT) has emerged as one of the most promising technologies in multiphase flow measurement due to its low cost and non-invasive nature. However, the inherent nonlinear characteristics between capacitance and permittivity, caused by uneven sensitivity distribution in ECT sensitivity fields, remain a key challenge for improving imaging quality. This paper proposes a high-resolution ECT imaging model based on an adaptive KAN mechanism (ECT-KHR). The model employs a two-stage network approach to address the non-linear mapping between capacitance and permittivity, thereby enhancing imaging resolution. Specifically, the first-stage network introduces KANs for adaptive fitting of the non-linear mapping. The second-stage network combines deep residual networks and sub-pixel convolution to repair and reconstruct low-resolution images from the first stage, thus reducing imaging artifacts and improving accuracy. Experimental results indicate that the ECT-KHR model achieves an average correlation coefficient exceeding 0.991, an average relative image error of approximately 0.098, and an average peak signal-to-noise ratio (PSNR) of 36.52. Notably, the model approaches direct algorithms in computation time, indicating superior accuracy and adaptability for multiphase flow monitoring under various flow regimes in oil and gas production processes.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102948"},"PeriodicalIF":2.3,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144203263","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":"CFD analysis of geometry configuration and sensor placement for hybrid triangular-T bluff body in vortex flowmeter","authors":"Payam Margan , Seyed Hassan Hashemabadi","doi":"10.1016/j.flowmeasinst.2025.102950","DOIUrl":"10.1016/j.flowmeasinst.2025.102950","url":null,"abstract":"<div><div>Vortex flowmeters are extensively employed in industrial settings for precise fluid flow measurement. This study aims to enhance vortex generation and pressure oscillation by extending tails in various lengths downstream of a triangular bluff body. Computational Fluid Dynamics (CFD) simulations were performed employing the Realizable k-ε turbulence model to study the geometry of the T-shaped bluff body and sensor placement for accurate flow measurement. A tail-to-width ratio (T/W) of 0.7 was identified as the most effective configuration for strong pressure fluctuations. Analysis of sensor placement indicated that the highest intensity of dynamic pressure oscillations was found at a distance of 7.9 times the width of the bluff body (X/W = 7.9) from the inlet. Additionally, variations in velocity, dynamic and static pressure, and turbulent kinetic energy production and dissipation were investigated along the flowmeter's axis to confirm the ideal sensor location. Results demonstrated signal clarity and sensitivity of the flowmeter for the proposed geometry configuration and sensor placement, indicating the potential for improved measurement consistency. Rangeability assessment revealed a stable Strouhal number (0.26–0.27) over a broad range of Reynolds numbers, ensuring reliable performance across diverse flow rates compared to conventional flowmeters.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102950"},"PeriodicalIF":2.3,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144298338","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 study on flow characteristics and flow prediction of CO2 through a combinational flow regulator","authors":"Bin Qin , Jingwen Lin , Jiaxu Hao , Quan Zhang","doi":"10.1016/j.flowmeasinst.2025.102961","DOIUrl":"10.1016/j.flowmeasinst.2025.102961","url":null,"abstract":"<div><div>Flow regulators are extensively utilized in the flow control of pipeline systems, as the internal flow characteristics significantly affect the system's operational conditions. This study proposes a combinational flow regulator featuring four branch channels and orifice plates, aiming to improve CO<sub>2</sub> flow control and regulation precision. Initially, the variations in pressure, temperature, and flow rate during the passage of CO<sub>2</sub> through the combinational flow regulator are analyzed. Subsequently, the influence of pressure difference and the number of orifices on the flow rate is examined. Furthermore, an analysis of the effect of the orifice throttling area on pressure distribution leads to the establishment of a fitting equation. This equation correlates the pressure difference with parameters like the upstream pressure and the orifice throttling area. Finally, the original experimental data undergoes statistical analysis to develop a new correlation, which is employed to predict the flow rate under varying initial conditions. This research has significant implications for the regulation of CO<sub>2</sub> flow rates in flow regulators, which contributes to the enhancement of system stability and efficiency.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102961"},"PeriodicalIF":2.3,"publicationDate":"2025-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144254578","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":"Optimized design and test based on Fluent cyclone dust removal device","authors":"Haiyang Xu, Mingyu Luo, Yuyang Chen, Xiao Fu, Yilong Dong, Dejun Liu","doi":"10.1016/j.flowmeasinst.2025.102953","DOIUrl":"10.1016/j.flowmeasinst.2025.102953","url":null,"abstract":"<div><div>This study aimed to optimize the design of a cyclone dust removal device for a waste textile opening machine to improve the dust removal efficiency. Theoretical analysis and structural parameter design were conducted, followed by computational particle fluid mechanics simulations to investigate the gas-solid two-phase flow characteristics inside the device. The effects of the inlet aspect ratio, exhaust pipe diameter, and exhaust pipe insertion depth on the separation efficiency and pressure drop were analyzed using the Design-Expert software. The optimal combination of structural parameters was an inlet aspect ratio of 2:1, exhaust pipe diameter of 140 mm, and exhaust pipe insertion depth of 155 mm. An optimized cyclone dust removal device was fabricated and tested, demonstrating a dust removal efficiency of 87 %, which met the expected level and emission standards. The results of this study provide a valuable reference for the design of dust-removal devices for related machinery.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102953"},"PeriodicalIF":2.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144222681","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 novel underwater multi-dimensional tactile and flow velocity perception method based on micro thermoelectric generator","authors":"Yuncong Wang, Changxin Liu, Zhenyao Ma, Tong Shao, Kailin Lei, Peihan Huang, Xing Feng","doi":"10.1016/j.flowmeasinst.2025.102955","DOIUrl":"10.1016/j.flowmeasinst.2025.102955","url":null,"abstract":"<div><div>With the continuous advancement in ocean resource development and deep-sea exploration, the demands for underwater robots' environmental adaptability, reaction speed, and operational precision are increasingly growing. A novel underwater multi-dimensional tactile perception method based on the micro thermoelectric generator (MTEG) is proposed in this study, which is enabled to perceive underwater characteristic materials, water flow velocity, and water flow direction. By monitoring the voltage output changes resulting from temperature changes on the cold side of the MTEG module after heat exchange, this method utilizes the Seebeck effect to convert thermal energy into electrical energy, thereby achieving perception of the underwater environment. A theoretical model for underwater multi-dimensional tactile perception based on MTEG is established in this study, and theoretical models for underwater characteristic material perception, water flow velocity perception, and water flow direction perception are derived. The experimental results indicate that the perception unit can effectively identify characteristic materials with different thermal conductivity coefficients within 2 s and recognize water flow velocity changes within the range of −8 to 8 m/s, with a recognition accuracy of 0.5 m/s. Moreover, the water flow direction perception unit is capable of recognizing the direction of water flow under rapidly changing conditions and maintains a rapid response even in high-flow environments. The underwater multi-dimensional tactile perception method proposed in this study provides technical support for exploration and development operations of marine resources in complex marine environments.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"106 ","pages":"Article 102955"},"PeriodicalIF":2.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144190529","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-objective optimization of DBD plasma actuator characteristics for turbulent flow separation control over airfoils","authors":"A. Rahni, A. Jahangirian","doi":"10.1016/j.flowmeasinst.2025.102951","DOIUrl":"10.1016/j.flowmeasinst.2025.102951","url":null,"abstract":"<div><div>The optimal characteristics of a plasma actuator for effective control of high Reynolds number turbulent flow separation around airfoils are investigated. The actuator position on the airfoil and its voltage are chosen as variable parameters. A multi-objective optimization using a Genetic Algorithm is used with two objective functions of maximizing aerodynamic efficiency and minimizing power consumption. The numerical simulation of the plasma actuator effect on the flow is carried out using Maxwell equations for the electro-hydrodynamic (EHD) field coupled with Reynolds Averaged Navier-Stokes equations through the Suzen model. An algorithm is developed to automatically adjust the actuator position, generate the mesh, and analyze the flow for a Reynolds number of one million. A detailed analysis of the results revealed that the actuator position significantly impacts aerodynamic efficiency, depending on the airfoil type and voltage applied to the actuator. Further study is carried out to investigate the separation control by plasma actuator over two airfoils with similar thicknesses, i.e., NACA0012 and NACA4412. Results indicated that the optimal actuator position for the symmetric airfoil is the leading edge, while that of the cambered airfoil (NACA4412) is near the middle of the airfoil. Furthermore, increasing the voltage beyond a specific threshold results in a rise in the drag coefficient, thereby diminishing the aerodynamic efficiency. The optimization analysis ultimately demonstrated that the peak aerodynamic efficiency for NACA0012 and NACA4412 airfoils is achieved at distinct voltage levels, specifically 18 kV and 21–22 kV, respectively.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"105 ","pages":"Article 102951"},"PeriodicalIF":2.3,"publicationDate":"2025-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169512","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}
Yongping Liu , Linyue Wu , Fuqiang Wang , Changbin Dong
{"title":"Investigation of flow field simulation and pulsation performance of non-circular gear hydraulic motor","authors":"Yongping Liu , Linyue Wu , Fuqiang Wang , Changbin Dong","doi":"10.1016/j.flowmeasinst.2025.102954","DOIUrl":"10.1016/j.flowmeasinst.2025.102954","url":null,"abstract":"<div><div>The non-circular gear hydraulic motor is widely used in hydraulic transmission systems for mining and underground machinery, owing to its low velocity, high output torque, and compact structure. This paper focuses on the 4–6 type non-circular gear hydraulic motor as the research object. The influence of the coupling between the motor's internal flow field and the operation of the gear train on the motor's power pulsation performance is analysed using the mesh and particle-based methods. A three-dimensional fluid model of the motor is developed to systematically investigate the effects of pressure and flow velocity on the motor's stability. With regard to the pulsation rate of the motor, this study analyses the comparative relationship between the theoretical torque pulsation rate and the theoretical flow pulsation rate, while simultaneously considering the variation of the flow pulsation rate under the influence of oil entrapment in the gear teeth. The results show that the theoretical flow pulsation rate of the motor is basically consistent with the theoretical torque pulsation rate. However, when considering the oil entrapment in the motor gear teeth, the flow pulsation rate increases. In the flow field simulation, the flow velocity distribution in the flow field is found to be uneven. Specifically, high-velocity flow is formed in the air gap area, while in the area close to the sun gear and the inner gear ring, the flow is poor and stagnation phenomena occur, which aggravates the oil entrapment phenomenon. The findings of this study provide a theoretical basis for optimizing the performance of non-circular gear hydraulic motors and offer new insights into the simulation analysis of complex moving flow field, as well as the relationship between flow pulsation rate and oil entrapment characteristics.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"105 ","pages":"Article 102954"},"PeriodicalIF":2.3,"publicationDate":"2025-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144169511","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}