Experiments in Fluids最新文献

{"title":"Dynamics of vortex interaction and entrainment characteristics in inclined elliptic jets using sparse track-enhanced volumetric measurements","authors":"Xin Zeng,&nbsp;Hao Qu,&nbsp;Chuangxin He,&nbsp;Yingzheng Liu,&nbsp;Lian Gan","doi":"10.1007/s00348-025-04038-5","DOIUrl":"10.1007/s00348-025-04038-5","url":null,"abstract":"<div><p>This work is a further discussion about elliptical jet flows (Zeng et al. in Exp Fluids 64:142, 2023) by exploring how variations in nozzle shape enhance flow control efficiency. The study examines the dynamic evolution of vortex interactions and their positive effects on the entrainment of inclined elliptical jets (with inclination angles of 30° in both the major and minor planes) compared to non-inclined elliptical jets. Experiments were conducted at an aspect ratio (AR) of 2 and a Reynolds number of approximately 3000. Time-resolved tomographic particle image velocimetry (Tomo-PIV) and three-dimensional Lagrangian particle tracking (3D LPT) measurements were employed to capture the flow dynamics in detail. The Eulerian velocity field datasets obtained from Tomo-PIV are enhanced using high-precision tracks from 3D LPT measurements, improving the accuracy of velocity field reconstruction. Statistical analyses indicate that inclined elliptical jets exhibit greater mass entrainment characteristics and higher momentum flux compared to non-inclined elliptical jets. The power spectral densities (PSDs) and time-domain spectral proper orthogonal decomposition (td-SPOD) results reveal that for the major-plane inclined-A nozzle, both the leading and trailing vortex rings share the same dominant frequency of St = 0.28, suggesting that vortex pairing and merging in the 30° inclined-A jet may be a periodic process. After vortex merging at approximately <i>Y</i>/<i>D</i>_<i>e</i> ≈ 3.5, the first axis-switching is completed, indicating that axial switching is suppressed in the major-plane inclined-A elliptical jet compared to the non-inclined case. In contrast, for the minor-plane inclined-B jet, the dominant frequencies of the leading and trailing vortex rings are St = 0.28 and St = 0.61, respectively. In some instances, two consecutive large-scale vortex rings corresponding to SPOD mode (3,4) do not merge downstream; instead, they develop independently and eventually break down separately. At the axis-switching plane (<i>Y</i>/<i>D</i>_<i>e</i> = 2.5), during both the merging and axis-switching processes of vortex rings in the two inclined nozzles, a significant number of streamwise vortex structures are generated. This phenomenon substantially contributes to an increased mean entrainment rate, further enhancing the mixing characteristics of inclined elliptical jets.</p><h3>Graphical Abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143938173","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":"Data-driven spatiotemporal analysis of cloud cavitation by means of spectral proper orthogonal decomposition","authors":"Grigorios Hatzissawidis,&nbsp;Moritz Sieber,&nbsp;Kilian Oberleithner,&nbsp;Peter F. Pelz","doi":"10.1007/s00348-024-03949-z","DOIUrl":"10.1007/s00348-024-03949-z","url":null,"abstract":"<div><p>The global dynamics of cloud cavitation are not always obvious; cloud cavitation may exhibit chaotic, multimodal and intermittent behaviour, where dominant flow structures are hidden to the naked eye. To address this, spectral proper orthogonal decomposition (SPOD) is applied, a method that can continuously transition between proper orthogonal decomposition (POD) and discrete Fourier transformation (DFT)/dynamic mode decomposition (DMD). This provides the opportunity to break down the complex dynamics of interacting and transient processes into interpretable modal bases. Experiments were conducted in a high-speed cavitation tunnel using a two-dimensional NACA 0015 hydrofoil at a fixed Reynolds number of <span>(8 times 10^5)</span> and an incidence of <span>(12^circ)</span> for varying cavitation numbers. The cavitation was recorded using a synchronised dual-camera set-up with simultaneously captured pressure signals. Shockwave-driven and re-entrant flow-driven cloud shedding is identified, as well as the transition regime in between, exhibiting more complex behaviour. The transition from shockwave-driven to re-entrant flow-driven cloud cavitation is smooth, with shockwaves becoming more dominant as the cavitation number decreases. SPOD modes allow for a frequency and amplitude variation, which successfully decomposes the data into the dominant modes, whereas classical modal decomposition methods such as POD and DMD do not provide interpretable decompositions. SPOD grants access to a transient analysis of the data via the SPOD time coefficients. We validate the SPOD results using space–time plots and power spectral density (PSD) of the pressure signals, being in good agreement with the SPOD spatial modes and time coefficients. The complex time coefficients give access to instantaneous mode frequencies and allow calculating a standard deviation of the frequency modulation of the modes. The findings provide a deep insight into the spatial and temporal behaviour of cloud cavitation and support the understanding of its physics.</p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00348-024-03949-z.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918995","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}

{"title":"Noise control in tandem airfoil configurations using leading-edge serrations on the front airfoil","authors":"Xishuai Yu,&nbsp;Jianxi Zhou,&nbsp;Yong Li","doi":"10.1007/s00348-025-04033-w","DOIUrl":"10.1007/s00348-025-04033-w","url":null,"abstract":"<div><p>Passive noise control of a tandem NACA6412 airfoil is experimentally studied by applying sinusoidal serrations to the leading-edge of the front airfoil. The position of the rear airfoil in the vertical gap direction is adjusted to identify the position that results in the maximum reduction in far-field noise. Subsequently, detailed unsteady flow characteristics in the flow field are measured using particle image velocimetry (PIV). The far-field noise results indicate that, at the position of optimal noise reduction, the application of leading-edge serrations to the front airfoil significantly reduces turbulence interaction noise in the frequency range of <span>(text{700 }text{Hz} le fle {2000} text{Hz})</span>, with a maximum reduction of up to 10 dB. Analysis of the PIV results shows that leading-edge serrations can significantly decrease turbulence intensity and vorticity in the wake of the front airfoil, while also narrowing the influence range of vortex shedding and turbulence. Therefore, the positioning of the front and rear airfoils has a strong impact on the variation in turbulence interaction noise. The research concludes by emphasizing the effect of leading-edge serrations on the wake of airfoils. These findings can be applied to reduce noise in rotating machinery, such as guide blade rows, fan blade rows, and turbine blade rows.</p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143918994","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":"Measurement of quantitative heat flux on translucent surfaces using infrared thermography","authors":"Brian S. Kinsey,&nbsp;James A. S. Threadgill,&nbsp;Stuart A. Craig","doi":"10.1007/s00348-025-04030-z","DOIUrl":"10.1007/s00348-025-04030-z","url":null,"abstract":"<div><p>A general algorithm is presented for determining accurate surface temperatures and heat transfer measurements using infrared thermography on optically translucent materials. The algorithm is validated with experimental data collected on a additively manufactured hemisphere made of Formlabs Rigid 10K in the University of Arizona Mach 5 Ludwieg tube. The accuracy of the measurement was determined by comparing to independent heat transfer sensors within the model and theoretical heating models. The results show significantly improved accuracy when compared to measurements made with the opaque body assumption which substantially underestimates the surface temperature and heat flux.</p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143896738","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":"Complete solid-body rotation rate measurements of micro-plastic curved fibers in turbulence","authors":"Giuseppe C. A. Caridi,&nbsp;Vlad Giurgiu,&nbsp;Marco De Paoli,&nbsp;Alfredo Soldati","doi":"10.1007/s00348-025-04021-0","DOIUrl":"10.1007/s00348-025-04021-0","url":null,"abstract":"<p>In this study we quantify the uncertainty relative to a novel Lagrangian tracking technique to measure the complete solid-body rotation rate of anisotropic micro-plastic fibers. By exploiting their geometry—specifically, their elongation and curvature for tumbling and spinning rate measurements, respectively—we address a gap in the literature regarding the tracking of fibers’ unique orientation along their trajectories. The impact of fiber geometry and imaging parameters on the accuracy of the solid-body rotation rates measurements is investigated. The influence of spatial and temporal resolution on the measurement uncertainty is assessed on synthetic data. Experimental results obtained in a channel flow demonstrate the method’s potential to accurately detect rotations of fibers with lengths approaching the Kolmogorov scale.</p>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00348-025-04021-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143900713","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}

{"title":"Assessing the haemodynamics of the cerebral venous system anatomy in multiple sclerosis and a healthy control using in vivo and 3D printed in vitro modelling","authors":"Alexander Robert Bateman,&nbsp;Jeannette Lechner-Scott,&nbsp;Tracie Barber,&nbsp;Grant Alexander Bateman,&nbsp;Saadallah Ramadan,&nbsp;Shiami Luchow,&nbsp;Pujith Vijayaratnam","doi":"10.1007/s00348-025-04028-7","DOIUrl":"10.1007/s00348-025-04028-7","url":null,"abstract":"<div><p>This study aimed to compare computational fluid dynamics (CFD) results to those acquired in vivo with 4D Flow magnetic resonance imaging (MRI) and in vitro with a 3D printed model using pressure catheter manometry. The goal was to investigate the haemodynamics of the cerebral venous system (CVS) and assess the accuracy of the methodologies, to highlight any discrepancies between the techniques. One participant living with multiple sclerosis (MS) and one healthy control were recruited for this study. MRI was performed to generate 3D geometries of the anatomy and to compute blood flow rates at the boundaries, with 4D Flow MRI velocity streamlines for the control participant. CFD models were created for the two participants and simulated using the patient-specific boundary conditions. A 3D printed geometry of the MS participant was created and a flow loop experiment was conducted to measure the cerebral venous pressures. The venous pressures were found to be comparable to that observed in the CFD simulation. 4D Flow MRI velocity streamlines of the CVS were found to correspond well to the CFD findings, except for a few regions, which were likely impacted by the low resolution of the MRI. The use of all three methods enabled the successful validation of the velocity, flow features and pressure, and ensured that the haemodynamics of the CVS as resolved using CFD, were accurate. This highlights the potential for increased efficacy of the clinical outcomes of future studies that utilise such methods.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00348-025-04028-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892674","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}

{"title":"Exploring separation and reattachment in shear-thinning suspensions through pipe-wall ultrasound measurements","authors":"Giuseppe Rosi,&nbsp;Moira Barnes,&nbsp;Frieder Kaiser,&nbsp;David Rival","doi":"10.1007/s00348-025-04018-9","DOIUrl":"10.1007/s00348-025-04018-9","url":null,"abstract":"<div><p>To better understand how turbulent flow structures develop within shear-thinning suspensions (STSs), we investigate the behavior of a shear layer forming within an STS downstream of a sudden expansion with an expansion ratio of 0.5. Specifically, the shear-layer reattachment behavior downstream of an axisymmetric expansion is characterized through ultrasound imaging velocimetry (UIV) and through pressure measurements, and the observed behavior is used to surmise how the shear layer is modified within the STS. Four fluids are investigated, which include pure water, as well as three 1750 ppm xanthan-gum-in-water solutions mixed with non-reactive mineral microspheres at volume fractions of 0%, 15%, and 30%. Wall-pressure measurements were collected through pressure taps located at 0<i>h</i> to 25.8<i>h</i> downstream of the expansion with subsequent UIV measurements collected from 1<i>h</i> to 9<i>h</i> downstream of the expansion, where <i>h</i> is the step height and equals the difference between the pipe and throat radii. For single-phase cases, pressure-recovery profiles and UIV flow fields indicate a predictably large reattachment length at low Reynolds numbers, which shortens as the Reynolds number increases from <span>(O(10^2))</span> to <span>({O}(10^4))</span> and finally stabilizes at roughly 8<i>h</i>. In contrast, the STSs exhibit pressure-recovery and pipe-wall velocity profiles indicating a reattachment length that is consistently short (8<i>h</i>) and independent of Reynolds number. The results indicate that the suspended phase within the STSs causes the shear layer to diffuse far more rapidly, thereby promoting momentum transfer toward the wall, which results in a consistently short reattachment length.</p><h3>Graphic abstract</h3><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00348-025-04018-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892675","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}

{"title":"Experimental study on bubble pairs and induced flow fields using tomographic particle image velocimetry","authors":"Hanbin Wang,&nbsp;Yang Xu,&nbsp;Jinjun Wang","doi":"10.1007/s00348-025-04026-9","DOIUrl":"10.1007/s00348-025-04026-9","url":null,"abstract":"<div><p>Owing to their unique fluid dynamics, gas‒liquid two-phase flows, such as bubbly flows, are widely used in various engineering applications. This study utilized three-dimensional shadow image reconstruction (3D-SIR) and laser-induced fluorescence tomographic particle image velocimetry (LIF-TPIV) to perform a quantitative analysis of the three-dimensional morphology and motion of bubbles, as well as bubble-induced flow fields. By systematically varying the orifice spacing (<span>(s/{D}_{n})</span>, where <span>({D}_{n})</span> is the orifice inner diameter) among the values 3.3, 5, 6.7, and 8.3, we investigate the effects of distance on bubble interactions and flow dynamics. Our findings reveal that at <span>(s/{D}_{n})</span> = 3.3, the bubbles move very close to each other while rising. Distinct vortex rings form around each bubble near the orifice and merge as they rise, which increases flow transport, dissipation, and flow velocity between bubbles, leading to earlier bubble instability. Spectral analysis indicates that bubble spacing is coupled with the dominant flow frequency. As orifice spacing increases, bubble interactions weaken, resulting in independent vortex rings near the orifice that grow to approximately twice the bubble’s diameter before shedding secondary vortices. In these cases, regions of strong transport and dissipation are concentrated in the wake, and the flow velocity between bubbles remains relatively weak. Bubble instability primarily originates from the wake vortices. The aspect ratios of the bubbles align with the dominant flow frequency, indicating a coupling between flow dynamics and bubble morphology, although periodicity in bubble spacing weakens at larger spacings. These findings provide valuable insights into two-phase flow dynamics, especially in multiorifice bubbly flows. </p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143883609","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":"Impact of a core–shell compound droplet on a solid surface","authors":"I. Alkomy,&nbsp;M. Marengo,&nbsp;A. Amirfazli","doi":"10.1007/s00348-025-04022-z","DOIUrl":"10.1007/s00348-025-04022-z","url":null,"abstract":"<div><p>Droplet impact on solid surfaces is fundamental to many natural and industrial processes, from water distribution in agriculture to precision technologies like inkjet printing and fuel injection. Recent studies have increasingly focused on the complex dynamics of multi-component, core–shell droplets, driven by their widespread presence in fields such as targeted drug delivery, biofuels, and 3D printing. Understanding the outcome of the impact of compound droplets and their maximum spreading on a solid surface is needed. This research investigates the influence of the controlling parameters, namely a broad range of core size, the core and shell viscosities, and Weber number on the impact outcome and the maximum spreading. Experiments of water-in-oil compound drops impacting on glass surface were conducted up to the range of impact parameters below splashing threshold. An equivalent Weber number (<span>(overline{text{We} })</span>) was introduced to account for the core–shell interfacial energy. Results reveal that the size of the core and the viscosity of the shell play critical roles in determining impact behavior. Larger cores tend to enhance prompt splashing and rebound, while thicker shells dampen the rebound of the vertical jet formed by the core. Viscous cores significantly damped the rebound while had no influence on splashing. The maximum spreading factor is vastly affected by the shell layer viscosity rather than the core’s. The size of the core influences the maximum spreading in two different ways, varying the compound drop viscosity and increasing the core–shell interface. A quantitative framework for compound droplets impact on solid surfaces is established, focusing on impact outcome and maximum spreading. Distinct outcome regime boundaries and transitions are mapped within the parameter space of controlling parameters, while their influence and controllability on maximum spreading are systematically evaluated.</p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143871313","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":"Synthetic jet vortex rings impinging onto porous walls: a more comprehensive similarity parameter","authors":"Yang Xu,&nbsp;Haocheng Wang,&nbsp;Congyi Xu,&nbsp;Zhiyu Li,&nbsp;Jinjun Wang","doi":"10.1007/s00348-025-04023-y","DOIUrl":"10.1007/s00348-025-04023-y","url":null,"abstract":"<div><p>By combining the effects of synthetic jet Reynolds number (<i>Re</i>_<i>sj</i>), porous wall porosity (<i>ϕ</i>) and porous wall hole diameter (d_<i>h</i>*), Li et al. (AIAA J 58:722–732, 2020) and Xu et al. (Phys Fluids 33:035140, 2021) presented a dimensionless similarity parameter [(<i>Re</i>_<i>sj</i>²<i>d* </i>_<i>h</i>³)^<i>ϕ</i>] to characterize the interaction between synthetic jet vortex rings and a porous wall. To futher incorporate the jet-exit-to-wall distance (<i>H</i>^*) into this similarity parameter, an experimental study was conducted to inverstigate the effect of the jet-exit-to-wall distance (<i>H</i>^* = 2, 4, 6, and 8) on the impingement of synthetic jet vortex rings onto a porous wall under three Reynolds numbers (<i>Re</i>_<i>sj</i> = 300, 600, and 900). By establishing the relationship between the loss of jet momentum flux and the jet-exit-to-wall distance (<i>H</i>^*) at different <i>Re</i>_<i>sj</i>, a more comprehensive similarity parameter [(<i>Re</i>_<i>sj</i>²<i>d</i>_<i>h</i>^<i>*</i>3<i>H</i>^*−0.64)^<i>ϕ</i>] was derived to characterize this vortex rings-porous wall interaction. Given the substantial impact of <i>H</i>^* on the vortex ring strength upon the impingement, an effective interaction velocity (<i>V</i>_<i>j,eff</i> = <i>V</i>_<i>j</i>/<i>H</i>^*0.32±0.045, <i>V</i>_<i>j</i> is the characteristic velocity of the synthetic jet) was introduced, so that [(<i>Re</i>_<i>sj</i>²<i>d</i>_<i>h</i>^<i>*</i>3<i>H</i>^*−0.64)^<i>ϕ</i>] was transformed as [(<i>Re</i>_<i>eff</i>²<i>d</i>_<i>h</i>^<i>*</i>)^<i>ϕ</i>], where <i>Re</i>_<i>eff</i> was the Reynolds number based on <i>V</i>_<i>j,eff</i>. This new similarity parameter effectively characterized both the losses of the momentum flux and kinetic energy transport due to impinging onto a porous wall in over 50 cases from current and previous experiments, thus verifying its validity at least in the range of [(<i>Re</i>_<i>eff</i>²<i>d</i>_<i>h</i>^<i>*</i>)^<i>ϕ</i>] ≤ 1000.</p></div>","PeriodicalId":554,"journal":{"name":"Experiments in Fluids","volume":"66 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2025-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143850932","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}