This work presents a simulation analysis using a multi-objective evolutionary algorithm for the thermo-hydraulic behavior of staggered heat sinks whose fins have NACA 0040 airfoil profile.The results were compared wit...This work presents a simulation analysis using a multi-objective evolutionary algorithm for the thermo-hydraulic behavior of staggered heat sinks whose fins have NACA 0040 airfoil profile.The results were compared with a conventional pin fin heat sink with a circular profile.This study searched for the best thermo-hydraulic performance by translational and rotational positioning of the fins.It is worth mentioning that this work was carried out in two stages.In the first stage,the thermo-hydraulic behavior of the heat sink was studied moving the location of the upper array above the X-axis from to 2.25 mm and above the Y-axis from to 1.275 mm.The second stage examined-2.25-1.55the effects of fin rotation considering the results found in stage 1.However,in this second stage,both arrays were free to rotate.For the upper array,the rotation range was-25°to 25° and for the lower array the rotation range was-15° to 15°.It is worth mentioning that both stages were analyzed for a single Reynolds(Re)number value of 13,000.The optimization results using the multi-objective evolutionary algorithm showed that compared to a NACA 0040 heat sink with fixed,unrotated original configuration(C0),the NACA 0040 heat sink with any Position Configuration(PC)did not significantly improve the heat transfer.Then,the results found in the second stage showed that the effect of the rotation of both sets did not influence the increase in pressure drop.However,it was found that with the Optimal Position and Rotation Configuration(PRCoptimal),which is the optimized array from Stage 1(position)then optimized by rotation,there is a slightly higher Performance Evaluation Criterion(PEC)compared to the original C0 configuration by 7%.Finally,the proposed NACA 0040 heat sink with the optimal rotation and position setting(PRCoptimal)was found to have a PEC of 9%compared to a conventional pin fin heat sink.展开更多
The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinatio...The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinations of them were considered.The leaf-shaped design of the cooling pin fin enhances uniformity and synergy,effectively creating an optimized flow path that boosts cooling performance.Eight three-dimensional conjugate heat transfer models in staggered arrangement were developed using ANSYS-Fluent software.Aluminum6061material was used as the heat sinkmaterial and single-phase liquid water flowed through the rectangular channel where the Reynolds(R_(e))number varies from 40 to 100.Using the same boundary conditions as the software simulations,two leaf-shaped channels were printed to validate numerical models.Velocity field and temperature differences of the eight proposed leaf-shaped pin fins configurations were discussed by comparison with cylindrical pin fins.Based on the findings of this study,at a Reynolds number of 80,the Leaf B Staggered Array(LBSA)records a maximum temperature that is 0.72 K lower than that of the cylindrical pin fins arrangement.Additionally,the LBSA exhibits a reduction in the friction factor by approximately 33.3%relative to the circular pin fins array under the same R_(e).This implies that the design of LBSA has been optimized to provide better heat dissipation performance while maintaining lower energy consumption.Furthermore,the LBSA demonstrates the most favorable thermal-hydraulic performance index(TPI),which is 1.18 times higher than that of the circular pin fins arrangement at R_(e)=80.The temperature reduction and friction factor reduction of the lobed channel is more pronounced than that of the conventional cooling channel,highlighting its potential to increase heat transfer efficiency and reduce energy consumption in practical applications.展开更多
A distinguished category of operational fluids,known as hybrid nanofluids,occupies a prominent role among various fluid types owing to its superior heat transfer properties.By employing a dovetail fin profile,this wor...A distinguished category of operational fluids,known as hybrid nanofluids,occupies a prominent role among various fluid types owing to its superior heat transfer properties.By employing a dovetail fin profile,this work investigates the thermal reaction of a dynamic fin system to a hybrid nanofluid with shape-based properties,flowing uniformly at a velocity U.The analysis focuses on four distinct types of nanoparticles,i.e.,Al2O3,Ag,carbon nanotube(CNT),and graphene.Specifically,two of these particles exhibit a spherical shape,one possesses a cylindrical form,and the final type adopts a platelet morphology.The investigation delves into the pairing of these nanoparticles.The examination employs a combined approach to assess the constructional and thermal exchange characteristics of the hybrid nanofluid.The fin design,under the specified circumstances,gives rise to the derivation of a differential equation.The given equation is then transformed into a dimensionless form.Notably,the Hermite wavelet method is introduced for the first time to address the challenge posed by a moving fin submerged in a hybrid nanofluid with shape-dependent features.To validate the credibility of this research,the results obtained in this study are systematically compared with the numerical simulations.The examination discloses that the highest heat flux is achieved when combining nanoparticles with spherical and platelet shapes.展开更多
The current study generally aims to improve heat transfer in heat sinks by presenting a numerical analysis of natural convection of an enclosure with hot right and cool left walls,and thermally insulated top and botto...The current study generally aims to improve heat transfer in heat sinks by presenting a numerical analysis of natural convection of an enclosure with hot right and cool left walls,and thermally insulated top and bottom walls.The cold wall included configurations(half circle/half square)in various sizes(S=0.1,0.2,and 0.3),numbers(N=1,2,3,and 4),and locations(C=0.35,and 0.65).A heat sink is constructed of Aluminum attached to the hot wall,and composed of five fins with protrusions.Fins of the heat sink will be examined in a solid and porous structure.The enclosure is filled with a hybrid nanofluid of Nanoparticles(MWCNT and Fe3O4)and water.The current study utilized COMSOL Multiphysics software due to its efficacy in addressing scientific and technical challenges involving partial differential equations.The solving of the governing equations is achieved using the finite element method with various parameters:Rayleigh number(Ra=10^(3)–10^(6)),Darcy number(Da=10^(-2),10^(-3)),solid volume fraction(ϕ=0–0.06)to determine stream function,isotherms lines,and average Nusselt number(Nu).The results of numerical simulations show that heat sink with solid fins have a 97%higher stream function when Ra is raised from 10^(3) to 105.Whilst with porous fin heat sink,a stream function 96%for Da=10^(-3) and 94%for Da=10^(-2).Changing solid fins to porous increases stream functions by 9%at Da=10^(-3) and 20%at Da=10^(-2).It has been found that Ra increases Nu by 44%for solid fins and 50%for porous fins.Making solid fins porous increases Nu by 54%at Ra=10^(6).The high increase in the percentage of(Nu)indicates the importance of the improvement in heat transfer,and this distinguishes the results of the current study from previous studies.Nu values were found highest for(half square)compared to(half circle),with 2%increases for numbers,11.6%for sizes,and 11%for location.Solid volume fractions for all Ra at a solid-finned heat sink increased Nu by 23%.展开更多
Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation i...Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).展开更多
目的:评价丹蛭降糖胶囊对2型糖尿病患者FINS和IRI作用的有效性。方法:计算机检索中国生物医学文献数据库、中国期刊全文数据库、万方期刊数据库等相关资料,按照Cochrane系统评价的方法,客观评价纳入研究的质量,提取有效数据,采用Rev Man...目的:评价丹蛭降糖胶囊对2型糖尿病患者FINS和IRI作用的有效性。方法:计算机检索中国生物医学文献数据库、中国期刊全文数据库、万方期刊数据库等相关资料,按照Cochrane系统评价的方法,客观评价纳入研究的质量,提取有效数据,采用Rev Man 5.2软件进行Meta分析。结果:共纳入5个随机对照试验,包括294例患者。结果显示,丹蛭降糖胶囊能降低2型糖尿病患者FINS[MD=1.24,95%CI(0.90,1.59),P<0.01],降低IRI[MD=0.20,95%CI(0.14,0.27),P<0.01]。结论:丹蛭降糖胶囊对2型糖尿病患者FINS和IRI作用是有效的。展开更多
以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PL...以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PLC的数据通信功能,实现监控软件对PLC的远程监控。经过现场的测试和运行,该监控系统稳定可靠,性能较高。展开更多
基金funded by University of Guanajuato through Project Convocatoria Institucional de Investigacion Cientifica 2025,161/2025.
文摘This work presents a simulation analysis using a multi-objective evolutionary algorithm for the thermo-hydraulic behavior of staggered heat sinks whose fins have NACA 0040 airfoil profile.The results were compared with a conventional pin fin heat sink with a circular profile.This study searched for the best thermo-hydraulic performance by translational and rotational positioning of the fins.It is worth mentioning that this work was carried out in two stages.In the first stage,the thermo-hydraulic behavior of the heat sink was studied moving the location of the upper array above the X-axis from to 2.25 mm and above the Y-axis from to 1.275 mm.The second stage examined-2.25-1.55the effects of fin rotation considering the results found in stage 1.However,in this second stage,both arrays were free to rotate.For the upper array,the rotation range was-25°to 25° and for the lower array the rotation range was-15° to 15°.It is worth mentioning that both stages were analyzed for a single Reynolds(Re)number value of 13,000.The optimization results using the multi-objective evolutionary algorithm showed that compared to a NACA 0040 heat sink with fixed,unrotated original configuration(C0),the NACA 0040 heat sink with any Position Configuration(PC)did not significantly improve the heat transfer.Then,the results found in the second stage showed that the effect of the rotation of both sets did not influence the increase in pressure drop.However,it was found that with the Optimal Position and Rotation Configuration(PRCoptimal),which is the optimized array from Stage 1(position)then optimized by rotation,there is a slightly higher Performance Evaluation Criterion(PEC)compared to the original C0 configuration by 7%.Finally,the proposed NACA 0040 heat sink with the optimal rotation and position setting(PRCoptimal)was found to have a PEC of 9%compared to a conventional pin fin heat sink.
基金supported by the Shandong Provincial Natural Science Foundation,China(Grant ZR2024ME136).
文摘The growing need for enhanced heat dissipation is compelling the development of more effective heat exchangers.Innovation inspired by nature bionics,four types of leaf-shaped pin fins were proposed and four combinations of them were considered.The leaf-shaped design of the cooling pin fin enhances uniformity and synergy,effectively creating an optimized flow path that boosts cooling performance.Eight three-dimensional conjugate heat transfer models in staggered arrangement were developed using ANSYS-Fluent software.Aluminum6061material was used as the heat sinkmaterial and single-phase liquid water flowed through the rectangular channel where the Reynolds(R_(e))number varies from 40 to 100.Using the same boundary conditions as the software simulations,two leaf-shaped channels were printed to validate numerical models.Velocity field and temperature differences of the eight proposed leaf-shaped pin fins configurations were discussed by comparison with cylindrical pin fins.Based on the findings of this study,at a Reynolds number of 80,the Leaf B Staggered Array(LBSA)records a maximum temperature that is 0.72 K lower than that of the cylindrical pin fins arrangement.Additionally,the LBSA exhibits a reduction in the friction factor by approximately 33.3%relative to the circular pin fins array under the same R_(e).This implies that the design of LBSA has been optimized to provide better heat dissipation performance while maintaining lower energy consumption.Furthermore,the LBSA demonstrates the most favorable thermal-hydraulic performance index(TPI),which is 1.18 times higher than that of the circular pin fins arrangement at R_(e)=80.The temperature reduction and friction factor reduction of the lobed channel is more pronounced than that of the conventional cooling channel,highlighting its potential to increase heat transfer efficiency and reduce energy consumption in practical applications.
文摘A distinguished category of operational fluids,known as hybrid nanofluids,occupies a prominent role among various fluid types owing to its superior heat transfer properties.By employing a dovetail fin profile,this work investigates the thermal reaction of a dynamic fin system to a hybrid nanofluid with shape-based properties,flowing uniformly at a velocity U.The analysis focuses on four distinct types of nanoparticles,i.e.,Al2O3,Ag,carbon nanotube(CNT),and graphene.Specifically,two of these particles exhibit a spherical shape,one possesses a cylindrical form,and the final type adopts a platelet morphology.The investigation delves into the pairing of these nanoparticles.The examination employs a combined approach to assess the constructional and thermal exchange characteristics of the hybrid nanofluid.The fin design,under the specified circumstances,gives rise to the derivation of a differential equation.The given equation is then transformed into a dimensionless form.Notably,the Hermite wavelet method is introduced for the first time to address the challenge posed by a moving fin submerged in a hybrid nanofluid with shape-dependent features.To validate the credibility of this research,the results obtained in this study are systematically compared with the numerical simulations.The examination discloses that the highest heat flux is achieved when combining nanoparticles with spherical and platelet shapes.
文摘The current study generally aims to improve heat transfer in heat sinks by presenting a numerical analysis of natural convection of an enclosure with hot right and cool left walls,and thermally insulated top and bottom walls.The cold wall included configurations(half circle/half square)in various sizes(S=0.1,0.2,and 0.3),numbers(N=1,2,3,and 4),and locations(C=0.35,and 0.65).A heat sink is constructed of Aluminum attached to the hot wall,and composed of five fins with protrusions.Fins of the heat sink will be examined in a solid and porous structure.The enclosure is filled with a hybrid nanofluid of Nanoparticles(MWCNT and Fe3O4)and water.The current study utilized COMSOL Multiphysics software due to its efficacy in addressing scientific and technical challenges involving partial differential equations.The solving of the governing equations is achieved using the finite element method with various parameters:Rayleigh number(Ra=10^(3)–10^(6)),Darcy number(Da=10^(-2),10^(-3)),solid volume fraction(ϕ=0–0.06)to determine stream function,isotherms lines,and average Nusselt number(Nu).The results of numerical simulations show that heat sink with solid fins have a 97%higher stream function when Ra is raised from 10^(3) to 105.Whilst with porous fin heat sink,a stream function 96%for Da=10^(-3) and 94%for Da=10^(-2).Changing solid fins to porous increases stream functions by 9%at Da=10^(-3) and 20%at Da=10^(-2).It has been found that Ra increases Nu by 44%for solid fins and 50%for porous fins.Making solid fins porous increases Nu by 54%at Ra=10^(6).The high increase in the percentage of(Nu)indicates the importance of the improvement in heat transfer,and this distinguishes the results of the current study from previous studies.Nu values were found highest for(half square)compared to(half circle),with 2%increases for numbers,11.6%for sizes,and 11%for location.Solid volume fractions for all Ra at a solid-finned heat sink increased Nu by 23%.
基金supported by the National Key Research and Development Program(Grant no.2022YFC2805200,2020YFB1313200)the National Natural Science Foundation of China(Grant no.52001260,52201381,52371338)Ningbo Natural Science Foundation(Grant no.2022J062).
文摘Bionic manta underwater vehicles will play an essential role in future oceans and can perform tasks,such as long-duration reconnaissance and exploration,due to their efficient propulsion.The manta wings’deformation is evident during the swimming process.To improve the propulsion performance of the unmanned submersible,the study of the deformation into the bionic pectoral fin is necessary.In this research,we designed and fabricated a flexible bionic pectoral fin,which is based on the Fin Ray®effect with active and passive deformation(APD)capability.The APD fin was actively controlled by two servo motors and could be passively deformed to variable degrees.The APD fin was moved at 0.5 Hz beat frequency,and the propulsive performance was experimentally verified of the bionic pectoral fins equipped with different extents of deformation.These results showed that the pectoral fin with active–passive deformed capabilities could achieve similar natural biological deformation in the wingspan direction.The average thrust(T)under the optimal wingspan deformation is 61.5%higher than the traditional passive deformed pectoral fins.The obtained results shed light on the design and optimization of the bionic pectoral fins to improve the propulsive performance of unmanned underwater vehicles(UUV).
文摘目的:评价丹蛭降糖胶囊对2型糖尿病患者FINS和IRI作用的有效性。方法:计算机检索中国生物医学文献数据库、中国期刊全文数据库、万方期刊数据库等相关资料,按照Cochrane系统评价的方法,客观评价纳入研究的质量,提取有效数据,采用Rev Man 5.2软件进行Meta分析。结果:共纳入5个随机对照试验,包括294例患者。结果显示,丹蛭降糖胶囊能降低2型糖尿病患者FINS[MD=1.24,95%CI(0.90,1.59),P<0.01],降低IRI[MD=0.20,95%CI(0.14,0.27),P<0.01]。结论:丹蛭降糖胶囊对2型糖尿病患者FINS和IRI作用是有效的。
文摘以欧姆龙公司CP1H型号的PLC为应用背景,设计了基于Host Link FINS协议的PLC设备远程监控系统。该文提出了基于串口的远程通信方案,并且详细分析了Host Link FINS协议的结构和指令格式,用MFC实现了监控软件的设计,完成监控软件与欧姆龙PLC的数据通信功能,实现监控软件对PLC的远程监控。经过现场的测试和运行,该监控系统稳定可靠,性能较高。
