International Journal of Heat and Fluid Flow最新文献

{"title":"Influence of natural gas composition and operating conditions on the phase change of dry gas seals for pipeline compressors","authors":"Fan Wu,&nbsp;Jinbo Jiang,&nbsp;Xudong Peng,&nbsp;Liming Teng,&nbsp;Minfeng Yu","doi":"10.1016/j.ijheatfluidflow.2025.109832","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109832","url":null,"abstract":"<div><div>Dry gas seal is critical component in pipeline natural gas compressor, with phase change between sealing faces being a major cause of failure. This paper focuses on spiral groove dry gas seals at 8–20 MPa, considering different sealing medium and real fluid effects. A thermohydrodynamic lubrication model is established, and solved using the finite difference method. The paper analyzes the differences in phase change behavior of pure components of natural gas, binary and multi-component natural gas mixtures. Based on the <em>p</em>-<em>H</em> diagram, obtain the minimum inlet temperature to prevent phase change of the sealing medium. The results show that CH₄ and N₂ are less likely to undergo phase changes, while C₂H₆ and CO₂ have similar phase change behaviors. Heavier hydrocarbons are more prone to phase changes. Phase changes of binary or multi-component mixture primarily occur near the inner diameter of the sealing face or at the leakage outlet, with the gas mass fraction in the gas–liquid two-phase region usually exceeding 0.9. Under the parameters calculated in this paper, the minimum sealing face inlet temperatures to prevent phase change for a typical natural gas sample at inlet pressures of 12 MPa, 15 MPa and 20 MPa are approximately 278 K, 288 K and 298 K, respectively.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109832"},"PeriodicalIF":2.6,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143829252","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 and numerical investigation of the acoustic resonance mechanism of the heat exchanger tube","authors":"Sheng Tian,&nbsp;Guofeng Huang,&nbsp;Wei Tan","doi":"10.1016/j.ijheatfluidflow.2025.109838","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109838","url":null,"abstract":"<div><div>In this paper, the heat exchanger tube is simplified as a single cylinder and the acoustic resonance mechanism of the single cylinder is investigated by a combination of experiments and numerical simulations. It is found that the peak acoustic pressure during acoustic resonance reaches 5.53 Pa and the fluctuation velocity reaches 0.7 m/s for a cylinder with a diameter of 12 mm. At the same time, the onset of acoustic resonance is delayed as the diameter increases until a higher flow velocity is reached − from about 20.8 m/s for a cylinder with a diameter of 10 mm to 30 m/s for a cylinder with a diameter of 14 mm. Numerical simulations analysed the evolution of the flow field during acoustic resonance by adjusting the numerical boundary conditions. The results show that the perturbation amplitude has a significant effect on the lift coefficient at the cylinder surface. When a perturbation of 10 % of <em>U</em>₀ is applied, the lift coefficient amplitude increases by 32.73 % compared to the undisturbed case.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109838"},"PeriodicalIF":2.6,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143824543","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":"Simulation and mechanism of the synergistic drag reduction performance of two types of microgroove surfaces and mucus","authors":"Kaisheng Zhang ,&nbsp;Jing Li ,&nbsp;Chuangchuang Zhang ,&nbsp;Jing Zhang ,&nbsp;Baocheng Zhang","doi":"10.1016/j.ijheatfluidflow.2025.109837","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109837","url":null,"abstract":"<div><div>Wall friction resistance during underwater travel reduces propulsion efficiency and generates significant noise. While several drag reduction methods inspired by bionic principles have been proposed, they often fail to sustain high drag reduction over time. In this study, we optimize conventional rectangular grooves and design two new groove structures, with mucus secretion pores positioned below them. Rheological experiments on various drag-reducing agents reveal that the bionic mucus follows the Carreau model, and simulations identify the most effective mucus for drag reduction. A hydrodynamic model is developed to examine the synergistic effect of the drag-reducing grooves and bionic mucus, which is solved using large vortex simulations and analyzed accordingly. The results indicate that the highest drag reduction rate (37.5 %) is achieved when the mucus secretion velocity is 0.25 m/s in the curved groove. Using vortex dynamics theory, we propose a function that relates drag reduction rate to vortex volume for quantitative analysis. The theoretical calculations show a positive correlation between drag reduction and mucus secretion speed, consistent with the simulation results. We conclude that the drag reduction mechanism involves the combination of microgrooves and mucus, which reduces the number and density of vortex structures near the wall, slows their evolution, and weakens turbulence intensity, leading to drag reduction. By integrating simulation and theory, this study offers a reference for theoretical drag reduction calculations and presents new insights for designing drag-reducing surfaces.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109837"},"PeriodicalIF":2.6,"publicationDate":"2025-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143820684","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":"Transition to turbulence of an incompressible flow past a multi-element airfoil: Mean-flow dynamics","authors":"Ming Teng ,&nbsp;Catherine Mavriplis","doi":"10.1016/j.ijheatfluidflow.2025.109825","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109825","url":null,"abstract":"<div><div>The present study explores the transition scenarios of an incompressible flow past an airfoil in a 30P30N configuration. Three low chordwise Reynolds numbers are considered: <span><math><mrow><mi>R</mi><msub><mrow><mi>e</mi></mrow><mrow><mi>c</mi></mrow></msub><mo>=</mo><mn>0</mn><mo>.</mo><mn>832</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span>, <span><math><mrow><mn>1</mn><mo>.</mo><mn>270</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span> and <span><math><mrow><mn>1</mn><mo>.</mo><mn>830</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mn>4</mn></mrow></msup></mrow></math></span>, respectively. The angle of attack is fixed at 4.0 degrees. A series of well-resolved three-dimensional direct numerical simulations are implemented via a high-order spectral element method. The present work aims to examine the mean-flow behavior and address the fundamental instability mechanisms that govern the transition routes in three <span><math><mrow><mi>R</mi><msub><mrow><mi>e</mi></mrow><mrow><mi>c</mi></mrow></msub></mrow></math></span> cases. The focus is placed on a quantitative analysis through mean statistics, but also monitors the evolution of instantaneous coherent structures. In addition to the conventional aerodynamic parameters, i.e., drag and lift coefficients, and pressure and skin-friction coefficients, etc., the present study discusses low- and higher-order statistics systematically including both Reynolds stresses and budget analysis of turbulent kinetic energy (TKE). An analysis of the TKE budget reveals that, despite the differences in <span><math><mrow><mi>R</mi><msub><mrow><mi>e</mi></mrow><mrow><mi>c</mi></mrow></msub></mrow></math></span> considered, the overall characteristics of the budget remain qualitatively the same. In cases with a separation bubble, the Kelvin–Helmholtz instability mechanism acts as a local amplifier, driving the growth of the perturbations along the inflection point. Pairs of longitudinal counter-rotating vortices are pronounced near the main-element leading edge, bearing a qualitative similarity to the so-called Görtler vortices. Both the inviscid Rayleigh criterion and Görtler number indicate regions of strong centrifugal effect and imply a likelihood of centrifugal instability.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109825"},"PeriodicalIF":2.6,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143798599","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":"Investigate the impact of different fin configurations arranged in-line on the double-pipe heat exchanger’s hydrothermal response","authors":"Haya Hussein ,&nbsp;Basim Freegah ,&nbsp;Qasim Saleh","doi":"10.1016/j.ijheatfluidflow.2025.109834","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109834","url":null,"abstract":"<div><div>The target of the present study is to investigate the effect of fin configuration and split in-line arrangement on the response of a DPHX’s hydrothermal system. The effect of both fin configurations, namely, longitudinal and wavy, was considered in this study. The ANSYS Fluent 2022 R1 software is used to create the 3D models and get the numerical results. To estimate the hydrothermal response of the heat exchanger, several parameters, such as the friction factor, thermal resistance, and Nu number are analyzed. A comparison between the numerical results and experimental findings for the traditional model is conducted to verify the numerical results, and the comparison showed good agreement between them. The results have shown that the hydrothermal response of a double pipe heat exchanger is affected by the fin configuration. Among all the models under investigation, Model D, characterized by eight fins arranged in a wavy pattern, emerged as the most optimal. It exhibited a Nu number that was 46.39 percent higher compared to the conventional model. Furthermore, it should be noted that models B and D exhibit the most superior overall performance factor values. Furthermore, the results indicated that models B and D exhibit an overall performance factor value of 1.330 and 1.313, respectively.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109834"},"PeriodicalIF":2.6,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777512","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":"Ammonia usage instead of hydrogen in Methane-Hydrogen Blended fuel mixture under highly preheated and dilution Condition: Chemical Perspective","authors":"Amir Mardani ,&nbsp;Hanyoung Kim ,&nbsp;Sechul Oh ,&nbsp;Kyung Chun Kim","doi":"10.1016/j.ijheatfluidflow.2025.109826","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109826","url":null,"abstract":"<div><div>This study investigates the replacement of hydrogen with ammonia in a burner simulating the Moderate or Intense Low-Oxygen Dilution (MILD) combustion regime for methane/hydrogen. Ammonia is a hydrogen carrier with fewer concerns regarding safety, cost, and transportation than hydrogen; however, it has some other drawbacks regarding reactivity and pollutant formation. The effects on flame structure and NOx formation are examined using three detailed chemical mechanisms: GRI, Okafor, and Sandiego, to isolate the influence of chemical mechanisms in the analysis. A RANS approach with the Eddy Dissipation Combustion (EDC) model, along with zero-dimensional well-stirred reactor models, focuses specifically on the MILD region. Ammonia replaces hydrogen in a methane/hydrogen mixture, with a maximum substitution of 50%. The results indicate that ammonia enhances methane ignition routes and its conversion to CO compared to hydrogen within the studied range. Additionally, contradictory combustion efficiency behaviors related to ammonia slip and NOx formation can be mitigated through high dilution for NOx control and high preheating for ammonia control. The addition of ammonia leads to an expansion of the heat release area while simultaneously boosting both NOx and DeNOx chemical pathway.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109826"},"PeriodicalIF":2.6,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777594","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":"Turbulent heat transfer and secondary flows in a non-uniformly heated pipe with temperature-dependent fluid properties","authors":"A. Antoranz ,&nbsp;O. Flores ,&nbsp;M. García-Villalba","doi":"10.1016/j.ijheatfluidflow.2025.109791","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109791","url":null,"abstract":"<div><div>The influence of temperature-dependent fluid properties in a turbulent pipe flow with sinusoidal heat flux boundary conditions is studied. Four cases with increasing sensitivity to temperature variations, representative of molten salts in solar heat receivers, are calculated by means of direct numerical simulation. The computations have been performed with a reference friction Reynolds number equal to 180 and a reference Prandtl number equal to 0.7. It is found that the fluid properties variations result in an enhancement (damping) of the flow and temperature fluctuations on the cold (hot) side of the pipe. Small secondary motions of Prandtl second kind are found to occur with a significant impact on the vertical heat flux, accounting for one third of the total heat flux in the most sensitive case. Finally, the effect of the variable fluid properties in integral quantities like friction coefficient and Nusselt number is quantified.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109791"},"PeriodicalIF":2.6,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777511","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":"Self-similarity in the logarithmic region of turbulence intensity in high-Reynolds-number pipe flow","authors":"Noriyuki Furuichi ,&nbsp;Marie Ono ,&nbsp;Yoshiyuki Tsuji","doi":"10.1016/j.ijheatfluidflow.2025.109836","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109836","url":null,"abstract":"<div><div>Establishing a scaling law for the turbulence intensity profile of wall-bounded flows at high Reynolds numbers has been an important theme in fluid dynamics and is increasingly linked to studies on Townsend’s attached eddy hypothesis. In this paper, the self-similarity of turbulence statistics for the three velocity components, derived from the assumption of attached eddy hypothesis, is examined using detailed experimental data for pipe flow from <em>Re</em>_τ = 4200 to 20,750 measured by laser Doppler velocimetry at the High Reynolds Number Actual Flow Facility (Hi-Reff). The region where probability density functions (PDFs) of velocity fluctuations for all three velocity components exhibit similar form was identified around <em>y</em>⁺=220 ∼ 720 through Kullback-Leibuler divergence (KLD) analysis. This region, referred to as the <em>identical PDF region</em>, is approximately located at the outer region of the Reynolds stress peak. Within this region, turbulence statistics for all velocity components exhibit self-similarity. Conversely, in the logarithmic region of the turbulence intensity profile −previously observed to approximately overlap with the logarithmic region of the mean velocity profile- the PDFs are not invariant, and turbulence statistics do not exhibit self-similarity. These findings suggest that the characteristics of the turbulence statistics in the identical PDF region align more closely with the predictions of the attached eddy hypothesis than those in the conventional logarithmic region.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109836"},"PeriodicalIF":2.6,"publicationDate":"2025-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777079","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":"Turbulent actuation of the inlet flow for a boundary layer with a mild adverse pressure gradient","authors":"Ehsan Asgari,&nbsp;Mohammad Saeedi","doi":"10.1016/j.ijheatfluidflow.2025.109829","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109829","url":null,"abstract":"<div><div>In this paper, we propose an upstream tripping method for turbulence generation in large-eddy simulation of a boundary layer that separates due to an adverse pressure gradient. High-order spectral-element method is used for the numerical simulation and an arc-type trip is located near the inlet boundary of the configuration with a mild adverse pressure gradient. We investigate how the trip height, position, number as well as the inlet velocity profile affect the downstream flow characteristics. Also, we examine how the resulting turbulent boundary layer separates to form a shear layer. The tripping technique is compared with a previously validated precursor method in terms of computational cost, accuracy and effort. Validation is conducted using a reference experiment in terms of separation and reattachment locations. Instantaneous flowfield and the first- and second-order statistics demonstrate the strong performance of the tripping cases. The results suggested that the tripping method outperforms the precursor approach in both accuracy and computational cost.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"115 ","pages":"Article 109829"},"PeriodicalIF":2.6,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777078","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":"Quantitative experiment and numerical simulation on sub-critical and supercritical CO2-N2 multiphase jet flows","authors":"Wangping Xi ,&nbsp;Dong Yang ,&nbsp;Pavel Skripov ,&nbsp;Lin Chen","doi":"10.1016/j.ijheatfluidflow.2025.109830","DOIUrl":"10.1016/j.ijheatfluidflow.2025.109830","url":null,"abstract":"<div><div>Supercritical fluid jets have found widespread applications in industrial fields such as aerospace propulsion and fuel mixing enhancement. Due to the complex property variations of fluids in these practical applications, accurately capturing the flow characteristics in multiphase jet processes has become a significant challenge. In this study, the high-precision non-contact measurement technique is combined with numerical simulation to realize quantitative measurement and analysis under sub/supercritical conditions. The study shows that the simulation accurately depicts the jet characteristics and verifies the feasibility of the numerical simulation method. Under subcritical conditions, the jet interface is clearer, and the mixing is dependent on the entrainment of the turbulent shear layer, with large instability and local oscillations. Under subcritical conditions, the jet interface appears clearer, and mixing is influenced by the entrainment of the turbulent shear layer, characterized by significant instabilities and local oscillations. Under supercritical conditions, the density distribution becomes smoother, leading to enhanced mixing and diffusion of fluids. This phenomenon is closely associated with the higher diffusivity and lower surface tension of supercritical fluids. Jets in this state are governed by a diffusion mechanism involving high-density CO₂ and low-density N₂, resulting in more ambiguous interfaces between the fluids due to the solubility of supercritical CO₂. This study aims to elucidate the flow behavior of supercritical multiphase jets, thereby providing a theoretical foundation and experimental support for related industrial applications.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"114 ","pages":"Article 109830"},"PeriodicalIF":2.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143759073","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}