Pub Date : 2025-02-27DOI: 10.1016/j.flowmeasinst.2025.102869
Oliver Büker , Krister Stolt , Corinna Kroner , Alexander Borchling , Manfred Werner , Günter Hagemann , Heiko Warnecke
The maritime sector is working hard to reduce greenhouse gas emissions. Overall, the shipping industry is under considerable pressure to identify innovative solutions, including a transition from conventional to cleaner fuels by 2050.
The most promising future fuels are ammonia, ethanol and methanol, which have lower viscosities than current fuels. These new generation fuels are sustainable and have the potential to significantly reduce greenhouse gas emissions.
Positive displacement meters are one of the most common types of flow meters used to measure fuel in the marine sector. However, they usually require a certain viscosity to perform properly. The aim of this study is to investigate the measurement performance of a prototype positive displacement fuel consumption meter capable of measuring next generation marine fuels and fuel blends with these and established fuels. The paper outlines the development of the prototype and how it was subsequently improved. Measurements were carried out on the prototype with fuels of different viscosities and line pressures relevant to shipping. The results prove that the meter operates almost independently of viscosity and pressure, making it suitable to accurately measure today's (current fuels), tomorrow's (blended fuels) and future fuels. Finally, suggestions for further improvements are given.
{"title":"Development of a prototype for measuring the fuel consumption of ocean-going ships","authors":"Oliver Büker , Krister Stolt , Corinna Kroner , Alexander Borchling , Manfred Werner , Günter Hagemann , Heiko Warnecke","doi":"10.1016/j.flowmeasinst.2025.102869","DOIUrl":"10.1016/j.flowmeasinst.2025.102869","url":null,"abstract":"<div><div>The maritime sector is working hard to reduce greenhouse gas emissions. Overall, the shipping industry is under considerable pressure to identify innovative solutions, including a transition from conventional to cleaner fuels by 2050.</div><div>The most promising future fuels are ammonia, ethanol and methanol, which have lower viscosities than current fuels. These new generation fuels are sustainable and have the potential to significantly reduce greenhouse gas emissions.</div><div>Positive displacement meters are one of the most common types of flow meters used to measure fuel in the marine sector. However, they usually require a certain viscosity to perform properly. The aim of this study is to investigate the measurement performance of a prototype positive displacement fuel consumption meter capable of measuring next generation marine fuels and fuel blends with these and established fuels. The paper outlines the development of the prototype and how it was subsequently improved. Measurements were carried out on the prototype with fuels of different viscosities and line pressures relevant to shipping. The results prove that the meter operates almost independently of viscosity and pressure, making it suitable to accurately measure today's (current fuels), tomorrow's (blended fuels) and future fuels. Finally, suggestions for further improvements are given.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"104 ","pages":"Article 102869"},"PeriodicalIF":2.3,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526694","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 : 2025-02-25DOI: 10.1016/j.flowmeasinst.2025.102865
Dongmei Wang , Dan Zhang , Yang Wu , Dandi Yang , Peng Wang , Jingyi Lu
The safe operation of oil and gas pipelines is of vital importance for maintaining national energy security. Therefore, the implementation of efficient pipeline leakage detection is an important link to ensure the safe and stable operation of pipelines. In this paper, a pipeline leakage detection method based on an improved spiking residual network is proposed. First, a coding method is proposed to encode the original signal into a spiking sequence. The input oil and gas pipeline signals are encoded using short-time Fourier transform combined with spatial gating mechanism and LIF neurons. Second, wavelet convolution was introduced to improve the original spiking residual network. Finally, the improved spiking residual network is used to classify the pipeline signals after the coding process. The experimental results show that the classification accuracy of the model proposed in this paper reaches 100 % on the original signal data, and 95.62 % with the addition of 5 dB Gaussian white noise, which effectively shows that the method has high accuracy and strong robustness, and can effectively improve the oil and gas pipeline leakage detection effect.
油气管道的安全运行对于维护国家能源安全至关重要。因此，实施高效的管道泄漏检测是确保管道安全稳定运行的重要环节。本文提出了一种基于改进型尖峰残差网络的管道泄漏检测方法。首先，提出一种编码方法，将原始信号编码为尖峰序列。输入的油气管道信号通过短时傅立叶变换结合空间门控机制和 LIF 神经元进行编码。其次，引入小波卷积来改进原始的尖峰残差网络。最后，利用改进后的尖峰残差网络对编码后的管道信号进行分类。实验结果表明，本文提出的模型在原始信号数据上的分类准确率达到 100%，在加入 5 dB 高斯白噪声后的分类准确率达到 95.62%，有效说明了该方法具有较高的准确率和较强的鲁棒性，能有效提高油气管道泄漏检测效果。
{"title":"Leakage fault diagnosis of oil and gas pipelines based on improved spiking residual network","authors":"Dongmei Wang , Dan Zhang , Yang Wu , Dandi Yang , Peng Wang , Jingyi Lu","doi":"10.1016/j.flowmeasinst.2025.102865","DOIUrl":"10.1016/j.flowmeasinst.2025.102865","url":null,"abstract":"<div><div>The safe operation of oil and gas pipelines is of vital importance for maintaining national energy security. Therefore, the implementation of efficient pipeline leakage detection is an important link to ensure the safe and stable operation of pipelines. In this paper, a pipeline leakage detection method based on an improved spiking residual network is proposed. First, a coding method is proposed to encode the original signal into a spiking sequence. The input oil and gas pipeline signals are encoded using short-time Fourier transform combined with spatial gating mechanism and LIF neurons. Second, wavelet convolution was introduced to improve the original spiking residual network. Finally, the improved spiking residual network is used to classify the pipeline signals after the coding process. The experimental results show that the classification accuracy of the model proposed in this paper reaches 100 % on the original signal data, and 95.62 % with the addition of 5 dB Gaussian white noise, which effectively shows that the method has high accuracy and strong robustness, and can effectively improve the oil and gas pipeline leakage detection effect.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"104 ","pages":"Article 102865"},"PeriodicalIF":2.3,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526693","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 : 2025-02-23DOI: 10.1016/j.flowmeasinst.2025.102847
Stephan Wernli , Lilach Goren Huber , Nicolas P. Avdelidis , Alfred Rieder
The Coriolis mass flow meter is a critical instrument used in various industries for the precise measurement of mass flow rate and density of a fluid. Despite its widespread use, the impact of entrained particles within the fluid can significantly affect the accuracy of the meter, leading to potential errors and inefficiencies. Previous calculations of the mass flow errors assumed that the entrained particles are uniformly distributed along the axis of the measurement tube. In this paper we extend the analytical investigation of the measurement errors beyond the previous work to the regime of non-uniform density distribution of the entrained particles. We provide a clear analysis of the contributions of various physical effects in this regime to the mass-flow measurement error.
{"title":"Coriolis massflow measurement errors due to inhomogeneous entrained particles: An analytical model","authors":"Stephan Wernli , Lilach Goren Huber , Nicolas P. Avdelidis , Alfred Rieder","doi":"10.1016/j.flowmeasinst.2025.102847","DOIUrl":"10.1016/j.flowmeasinst.2025.102847","url":null,"abstract":"<div><div>The Coriolis mass flow meter is a critical instrument used in various industries for the precise measurement of mass flow rate and density of a fluid. Despite its widespread use, the impact of entrained particles within the fluid can significantly affect the accuracy of the meter, leading to potential errors and inefficiencies. Previous calculations of the mass flow errors assumed that the entrained particles are uniformly distributed along the axis of the measurement tube. In this paper we extend the analytical investigation of the measurement errors beyond the previous work to the regime of non-uniform density distribution of the entrained particles. We provide a clear analysis of the contributions of various physical effects in this regime to the mass-flow measurement error.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102847"},"PeriodicalIF":2.3,"publicationDate":"2025-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143508814","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}
Steam, as a recyclable energy source, has a wide range of applications. The accurate measurement of steam flowrate is closely related to the selection and installation of steam flowmeters. Combining the advantages of differential pressure (DP) measurement and vortex street measurement methods, a vortex uniform velocity tube integrated sensor is designed in this paper. Based on the condensation weighing standard device of the national steam metering station, experimental measurements and performance verification are conducted on the sensor using superheated steam as the medium. The results show that the vortex uniform velocity tube integrated sensor designed in this study has a relative error(RE) of less than 1 % in measuring steam mass flow rate and steam density, and a repeatability of less than 0.7 %. This sensor can achieve high-precision measurement of steam under high temperature and high pressure.
{"title":"Research on steam flowrate measurement based on vortex uniform velocity tube integrated sensor","authors":"Lide Fang , Xinyuan Zhang , Zeqi Wang , Danlei Zhao , Yue Feng","doi":"10.1016/j.flowmeasinst.2025.102854","DOIUrl":"10.1016/j.flowmeasinst.2025.102854","url":null,"abstract":"<div><div>Steam, as a recyclable energy source, has a wide range of applications. The accurate measurement of steam flowrate is closely related to the selection and installation of steam flowmeters. Combining the advantages of differential pressure (DP) measurement and vortex street measurement methods, a vortex uniform velocity tube integrated sensor is designed in this paper. Based on the condensation weighing standard device of the national steam metering station, experimental measurements and performance verification are conducted on the sensor using superheated steam as the medium. The results show that the vortex uniform velocity tube integrated sensor designed in this study has a relative error(RE) of less than 1 % in measuring steam mass flow rate and steam density, and a repeatability of less than 0.7 %. This sensor can achieve high-precision measurement of steam under high temperature and high pressure.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102854"},"PeriodicalIF":2.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143480035","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 : 2025-02-21DOI: 10.1016/j.flowmeasinst.2025.102851
Xiaoxue Liu, Yaobao Yin, Yifan Wang, Weiqi Wang, Xinyi Wang, Hong Wang
The deflector jet servo valve (DJSV) is a critical component in modern hydraulic control systems, widely used in aerospace, industrial automation, and precision machinery due to its high response speed and reliability. The pilot stage, as a core component of the servo valve, plays a crucial role in converting the displacement signal from the torque motor into the pressure signal to drive the movement of the power stage spool valve. However, the pilot stage flow field structure of the DJSV is intricate, involving multiple phases of energy conversion, and existing studies lack a complete mathematical model that can accurately describe its performance. This limitation has hindered the optimization of servo valve design and performance analysis. To address this gap, this paper proposes a novel method for modeling and performance analysis of the pilot stage flow field of the DJSV. Based on the working principles of the pilot stage and the mechanisms of energy transfer and conversion during the jet flow process, the pilot stage jet flow is divided into five distinct phases to develop a mathematical model of the flow field. Furthermore, the performance of the pilot stage and the influence of key structural parameters are analyzed, then a mapping relationship between them is established. This paper conducted a pressure characteristic test of the pilot stage to verify the correctness of the proposed method. The proposed model offers significant practical value for optimizing servo valve design, reducing development time, and improving system performance in various industrial applications.
{"title":"The flow field modeling and performance analysis method for the pilot stage of deflector jet servo valve","authors":"Xiaoxue Liu, Yaobao Yin, Yifan Wang, Weiqi Wang, Xinyi Wang, Hong Wang","doi":"10.1016/j.flowmeasinst.2025.102851","DOIUrl":"10.1016/j.flowmeasinst.2025.102851","url":null,"abstract":"<div><div>The deflector jet servo valve (DJSV) is a critical component in modern hydraulic control systems, widely used in aerospace, industrial automation, and precision machinery due to its high response speed and reliability. The pilot stage, as a core component of the servo valve, plays a crucial role in converting the displacement signal from the torque motor into the pressure signal to drive the movement of the power stage spool valve. However, the pilot stage flow field structure of the DJSV is intricate, involving multiple phases of energy conversion, and existing studies lack a complete mathematical model that can accurately describe its performance. This limitation has hindered the optimization of servo valve design and performance analysis. To address this gap, this paper proposes a novel method for modeling and performance analysis of the pilot stage flow field of the DJSV. Based on the working principles of the pilot stage and the mechanisms of energy transfer and conversion during the jet flow process, the pilot stage jet flow is divided into five distinct phases to develop a mathematical model of the flow field. Furthermore, the performance of the pilot stage and the influence of key structural parameters are analyzed, then a mapping relationship between them is established. This paper conducted a pressure characteristic test of the pilot stage to verify the correctness of the proposed method. The proposed model offers significant practical value for optimizing servo valve design, reducing development time, and improving system performance in various industrial applications.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102851"},"PeriodicalIF":2.3,"publicationDate":"2025-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143487288","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 : 2025-02-20DOI: 10.1016/j.flowmeasinst.2025.102852
Han Lian-fu , Zhang Yin-hao , Wang Hai-xia , Gu Jian-fei , Liu Xingbin , Fu Chang-feng
PTV is an active study method of oil-water two-phase flow characteristic based on photogrammetry. It has advantages of undisturbed, no-contact and high measurement accuracy which directly related to the image quality. However, analogous oil droplet attachments on inner transparent pipe wall are often recorded as part of image, thus reducing measurement accuracy. To overcome the obstacle, it is necessary to identify and locate the outline of analogous oil droplet attachments. Extracting color and motion characters of oil-water two-phase flow images as features for clustering and applying K-means algorithm to identify and locate the outline of the analogous oil droplet attachment. K-means algorithm's clustering result is greatly affected by initial clustering centers and outlier data in practical applications, so Isolation Forest is adopted to improve K-means algorithm. The new algorithm proposed in this paper is called ILF-Kmeans. Simulation and experiment verification are carried out on ILF-Kmeans algorithm. Simulation results show that ILF-Kmeans algorithm has better clustering effect and higher identification accuracy than K-means algorithm; Experiment results show that measurement accuracy of PTV based on ILF-Kmeans to measure the oil phase velocity of oil-water two-phase flow increases by 4.25 %.
{"title":"Recognition of analogous oil droplet attached to transparent pipe wall","authors":"Han Lian-fu , Zhang Yin-hao , Wang Hai-xia , Gu Jian-fei , Liu Xingbin , Fu Chang-feng","doi":"10.1016/j.flowmeasinst.2025.102852","DOIUrl":"10.1016/j.flowmeasinst.2025.102852","url":null,"abstract":"<div><div>PTV is an active study method of oil-water two-phase flow characteristic based on photogrammetry. It has advantages of undisturbed, no-contact and high measurement accuracy which directly related to the image quality. However, analogous oil droplet attachments on inner transparent pipe wall are often recorded as part of image, thus reducing measurement accuracy. To overcome the obstacle, it is necessary to identify and locate the outline of analogous oil droplet attachments. Extracting color and motion characters of oil-water two-phase flow images as features for clustering and applying K-means algorithm to identify and locate the outline of the analogous oil droplet attachment. K-means algorithm's clustering result is greatly affected by initial clustering centers and outlier data in practical applications, so Isolation Forest is adopted to improve K-means algorithm. The new algorithm proposed in this paper is called ILF-Kmeans. Simulation and experiment verification are carried out on ILF-Kmeans algorithm. Simulation results show that ILF-Kmeans algorithm has better clustering effect and higher identification accuracy than K-means algorithm; Experiment results show that measurement accuracy of PTV based on ILF-Kmeans to measure the oil phase velocity of oil-water two-phase flow increases by 4.25 %.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102852"},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143471745","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 : 2025-02-20DOI: 10.1016/j.flowmeasinst.2025.102849
Parisa Ebadzadeh , Rasoul Daneshfaraz , Bahram Nourani , John Abraham
Sluice gates with a semi-cylindrical sill are flow control structures that are used in irrigation canals to regulate water level and flow discharge. To estimate the flow discharge through these structures, it is necessary to accurately estimate the discharge coefficient. The aim of this study is to present a new approach based on data-mining to accurately estimate the Cd based on experimental data. First, standalone data-mining models such as Artificial Neural Network (ANN) and Gaussian Process Regression (GPR) were developed. Then, to improve the performance of the standalone models, a multiple model (MM) strategy was used to develop new multiple models handled by ANN (MM-ANN) and GPR (MM-GPR). Next, an ensemble model (EM) strategy was developed. A total of 107 experiments were conducted to investigate the effect of the semi-cylindrical sill geometry on the discharge coefficient. 70 % of the data was reserved for the training phase, and the remaining 30 % for the testing phase. The ratio of energy head to sill width (h/b) and approach energy head to wetted parameter (h/P) were as input variables and the discharge coefficient (Cd) was an output variable. The outcomes of the multiple models and ensemble model were compared to the standalone methods using statistical metrics (R2, RE%, RMSE, and MAE) and graphical tools (Taylor, Violin, RE%, and scatter plots). The MM-ANN model with R = 0.951, R2 = 0.904, SI = 0.012, RE% = 0.891, MAE = 0.005, and RMSE = 0.007 outperformed the ANN, GPR, MM-GPR, and EM models in accuracy. The h/p variable had the greatest effect on the target variable of MM-ANN evidenced by a SHAP value of 0.45. The MM-ANN model provided reasonable estimates the experimental results. It is recommended to implement the multiple model strategy in order to improve the calculation accuracy of the models in this field.
{"title":"Estimating discharge coefficient of the sluice gate including, the semi-cylindrical sill utilizing multiple model strategy","authors":"Parisa Ebadzadeh , Rasoul Daneshfaraz , Bahram Nourani , John Abraham","doi":"10.1016/j.flowmeasinst.2025.102849","DOIUrl":"10.1016/j.flowmeasinst.2025.102849","url":null,"abstract":"<div><div>Sluice gates with a semi-cylindrical sill are flow control structures that are used in irrigation canals to regulate water level and flow discharge. To estimate the flow discharge through these structures, it is necessary to accurately estimate the discharge coefficient. The aim of this study is to present a new approach based on data-mining to accurately estimate the <em>C</em><sub><em>d</em></sub> based on experimental data. First, standalone data-mining models such as Artificial Neural Network (<em>ANN</em>) and Gaussian Process Regression (<em>GPR</em>) were developed. Then, to improve the performance of the standalone models, a multiple model (<em>MM</em>) strategy was used to develop new multiple models handled by <em>ANN</em> (<em>MM</em>-<em>ANN</em>) and <em>GPR</em> (<em>MM-GPR</em>). Next, an ensemble model (<em>EM</em>) strategy was developed. A total of 107 experiments were conducted to investigate the effect of the semi-cylindrical sill geometry on the discharge coefficient. 70 % of the data was reserved for the training phase, and the remaining 30 % for the testing phase. The ratio of energy head to sill width (<em>h/b</em>) and approach energy head to wetted parameter (<em>h/P)</em> were as input variables and the discharge coefficient (<em>C</em><sub><em>d</em></sub>) was an output variable. The outcomes of the multiple models and ensemble model were compared to the standalone methods using statistical metrics (<em>R</em><sup>2</sup>, <em>RE</em>%, <em>RMSE</em>, and <em>MAE</em>) and graphical tools (Taylor, Violin, <em>RE</em>%, and scatter plots). The <em>MM</em>-<em>ANN</em> model with <em>R</em> = 0.951, <em>R</em><sup>2</sup> = 0.904, <em>SI</em> = 0.012, <em>RE</em>% = 0.891, <em>MAE</em> = 0.005, and <em>RMSE</em> = 0.007 outperformed the <em>ANN</em>, <em>GPR</em>, <em>MM</em>-<em>GPR</em>, and <em>EM</em> models in accuracy. The <em>h/p</em> variable had the greatest effect on the target variable of <em>MM-ANN</em> evidenced by a <em>SHAP</em> value of 0.45. The <em>MM</em>-<em>ANN</em> model provided reasonable estimates the experimental results. It is recommended to implement the multiple model strategy in order to improve the calculation accuracy of the models in this field.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"104 ","pages":"Article 102849"},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552646","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 : 2025-02-20DOI: 10.1016/j.flowmeasinst.2025.102855
Navam Shrivastava, Anant Kumar Rai
In high-head hydropower plants, the Pelton injector is prone to erosion even for low sediment concentration and smaller size particles due to high flow velocities. Here, the effect of complex flow in a five-jet Pelton distributor is considered for analysing the erosion in the injector and distributor numerically. The discrete phase model based on an Eulerian-Lagrangian approach is used for tracking sediment particles. In this study, a good agreement of the obtained results with the experiments and field observations in a high-head hydropower plant validated the numerical methods selected. For larger-sized particles, a significant difference in the erosion among nozzles of the distributor was found. However, the difference in the erosion was reduced for smaller-sized particles. Further, erosion observed in the fifth nozzle was four times higher than the second nozzle considering 200 μm size particles during part-load conditions. Variation of sediment impact velocity due to change in sediment size has a similar trend for both the nozzle and needle surfaces. In contrast, variation in sediment concentration in the nozzle and needle resulted in an inverse relation with sediment size. The asymmetrical erosion pattern obtained for the nozzle is consistent with the erosion pattern from the prototype plant. Asymmetricity was also observed in the distribution of sediments in the jet, substantially for the fifth injector. The head loss at the third bifurcation is two times more at the full-load condition compared to the part-load condition.
{"title":"Numerical analysis of hydro-abrasive erosion in a five-jet Pelton turbine distributor","authors":"Navam Shrivastava, Anant Kumar Rai","doi":"10.1016/j.flowmeasinst.2025.102855","DOIUrl":"10.1016/j.flowmeasinst.2025.102855","url":null,"abstract":"<div><div>In high-head hydropower plants, the Pelton injector is prone to erosion even for low sediment concentration and smaller size particles due to high flow velocities. Here, the effect of complex flow in a five-jet Pelton distributor is considered for analysing the erosion in the injector and distributor numerically. The discrete phase model based on an Eulerian-Lagrangian approach is used for tracking sediment particles. In this study, a good agreement of the obtained results with the experiments and field observations in a high-head hydropower plant validated the numerical methods selected. For larger-sized particles, a significant difference in the erosion among nozzles of the distributor was found. However, the difference in the erosion was reduced for smaller-sized particles. Further, erosion observed in the fifth nozzle was four times higher than the second nozzle considering 200 μm size particles during part-load conditions. Variation of sediment impact velocity due to change in sediment size has a similar trend for both the nozzle and needle surfaces. In contrast, variation in sediment concentration in the nozzle and needle resulted in an inverse relation with sediment size. The asymmetrical erosion pattern obtained for the nozzle is consistent with the erosion pattern from the prototype plant. Asymmetricity was also observed in the distribution of sediments in the jet, substantially for the fifth injector. The head loss at the third bifurcation is two times more at the full-load condition compared to the part-load condition.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102855"},"PeriodicalIF":2.3,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464088","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 : 2025-02-19DOI: 10.1016/j.flowmeasinst.2025.102853
Shenglin Diao, Wenjun Wu, Ben Zhang, Li Wang
The external acoustic field characteristics of leakage from pipelines are crucial in assessing the feasibility of non-contact acoustic methods for pipeline leakage detection. This study explores the characteristics of such leakage in gas pipelines by coupling Computational Fluid Dynamics (CFD) flow field calculations with the acoustic software ACTRAN. Large Eddy Simulation (LES) was first employed to calculate the unsteady flow field during a leak of gas pipelines. To account for the high Mach number associated with gas pipeline leakage, the Möhring acoustic analogy method was employed to extract the aerodynamic noise source. This approach utilized time-averaged flow velocity data from the unsteady flow field as the background flow. The study further examined the characteristics of the external leakage sound source under varying fluid pressure conditions. Additionally, the near-field and far-field propagation characteristics of the sound source were analyzed using a combination of acoustic finite element and infinite element methods. The results demonstrate that a high-velocity jet region forms at the outlet of the leakage hole during a gas pipeline leak, generating a leakage sound source predominantly characterized by a quadrupole sound source. The peak sound pressure level of the leakage noise is primarily concentrated in the low-frequency range. While the pressure differential between the inside and outside of the pipeline influences the intensity of the sound source within the jet region, it does not significantly affect the frequency characteristics of the sound source. The strong sound source distribution largely coincides with the jet region, and the propagation of the leakage sound source along the jet direction is symmetric, with this symmetry maintained across varying distances.
{"title":"Numerical simulation of the external acoustic field characteristics of gas pipeline leakage","authors":"Shenglin Diao, Wenjun Wu, Ben Zhang, Li Wang","doi":"10.1016/j.flowmeasinst.2025.102853","DOIUrl":"10.1016/j.flowmeasinst.2025.102853","url":null,"abstract":"<div><div>The external acoustic field characteristics of leakage from pipelines are crucial in assessing the feasibility of non-contact acoustic methods for pipeline leakage detection. This study explores the characteristics of such leakage in gas pipelines by coupling Computational Fluid Dynamics (CFD) flow field calculations with the acoustic software ACTRAN. Large Eddy Simulation (LES) was first employed to calculate the unsteady flow field during a leak of gas pipelines. To account for the high Mach number associated with gas pipeline leakage, the Möhring acoustic analogy method was employed to extract the aerodynamic noise source. This approach utilized time-averaged flow velocity data from the unsteady flow field as the background flow. The study further examined the characteristics of the external leakage sound source under varying fluid pressure conditions. Additionally, the near-field and far-field propagation characteristics of the sound source were analyzed using a combination of acoustic finite element and infinite element methods. The results demonstrate that a high-velocity jet region forms at the outlet of the leakage hole during a gas pipeline leak, generating a leakage sound source predominantly characterized by a quadrupole sound source. The peak sound pressure level of the leakage noise is primarily concentrated in the low-frequency range. While the pressure differential between the inside and outside of the pipeline influences the intensity of the sound source within the jet region, it does not significantly affect the frequency characteristics of the sound source. The strong sound source distribution largely coincides with the jet region, and the propagation of the leakage sound source along the jet direction is symmetric, with this symmetry maintained across varying distances.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102853"},"PeriodicalIF":2.3,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143454659","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 : 2025-02-18DOI: 10.1016/j.flowmeasinst.2025.102850
Jiaxing Lu , Chenzhuo Ning , Feng Wu , Xiaobing Liu , Kai Luo , Fan Zhang , Yilong Qiu
To analyze the unsteady flow properties and their effect on the centrifugal pump performance, we employ a hybrid approach using numerical and experimental methods to evaluate and identify complex flow states. The pressure variations measured experimentally at the centrifugal pump's input and outlet are analyzed utilizing the continuous wavelet transform (CWT). The flow field data generated by numerical simulation is studied to analyze the distribution of pressure, turbulent kinetic energy and distribution of the velocity streamlines under different working conditions, the method of Dynamic Mode Decomposition (DMD) is utilized to examine distribution of vorticity within a centrifugal pump working under conditions of partial load and designed flow rate. The aim of this study was to investigate the link between the inlet and outlet pressure fluctuations of the pump and the flow instability. Using CWT analysis of the pump inlet and outlet pressure pulsation signal, the amplitude of the rotor frequency (f0) and twice the rotor frequency (2f0) increased significantly when the flow decreased. The decrease of flow rate promotes the scale and number of vortices, and also promotes the development of pump vibration strength. With the decrease of the flow rate, the vortex constantly diffuses from the suction side of the blade to the pressure side, the pressure at the impeller shows obvious heterogeneity, and the strength of the vortex structure also increases and gradually diffused, resulting in the obstruction of the flow channel. These findings provide a scientific basis for ensuring the stable operation of the centrifugal pump.
{"title":"Dynamic mode decomposition based investigation of unsteady flow characteristics and pressure pulsations in centrifugal pumps operating under partial load conditions for scientific advancement","authors":"Jiaxing Lu , Chenzhuo Ning , Feng Wu , Xiaobing Liu , Kai Luo , Fan Zhang , Yilong Qiu","doi":"10.1016/j.flowmeasinst.2025.102850","DOIUrl":"10.1016/j.flowmeasinst.2025.102850","url":null,"abstract":"<div><div>To analyze the unsteady flow properties and their effect on the centrifugal pump performance, we employ a hybrid approach using numerical and experimental methods to evaluate and identify complex flow states. The pressure variations measured experimentally at the centrifugal pump's input and outlet are analyzed utilizing the continuous wavelet transform (CWT). The flow field data generated by numerical simulation is studied to analyze the distribution of pressure, turbulent kinetic energy and distribution of the velocity streamlines under different working conditions, the method of Dynamic Mode Decomposition (DMD) is utilized to examine distribution of vorticity within a centrifugal pump working under conditions of partial load and designed flow rate. The aim of this study was to investigate the link between the inlet and outlet pressure fluctuations of the pump and the flow instability. Using CWT analysis of the pump inlet and outlet pressure pulsation signal, the amplitude of the rotor frequency <em>(f</em><sub>0</sub>) and twice the rotor frequency (2<em>f</em><sub>0</sub>) increased significantly when the flow decreased. The decrease of flow rate promotes the scale and number of vortices, and also promotes the development of pump vibration strength. With the decrease of the flow rate, the vortex constantly diffuses from the suction side of the blade to the pressure side, the pressure at the impeller shows obvious heterogeneity, and the strength of the vortex structure also increases and gradually diffused, resulting in the obstruction of the flow channel. These findings provide a scientific basis for ensuring the stable operation of the centrifugal pump.</div></div>","PeriodicalId":50440,"journal":{"name":"Flow Measurement and Instrumentation","volume":"103 ","pages":"Article 102850"},"PeriodicalIF":2.3,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143464087","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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