Shahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Simulation and analysis of chatter onset in orthogonal cutting process using an energy-based approachSimulation and analysis of chatter onset in orthogonal cutting process using an energy-based approach331347374310.22044/jsfm.2025.16071.3965FAMohammadGhorbaniDepartment of Mechanical Engineering, Shahreza Campus, University of Isfahan, IranMostafaSarjoughianDepartment of Mechanical Engineering, Shahreza Campus, University of Isfahan, IranJournal Article20250426This paper simulates workpiece vibrations in the orthogonal cutting process, from the initial engagement of the tool and workpiece, to conduct an in-depth investigation of chatter onset using an energy-based approach. For this purpose, the orthogonal cutting process of a disk is divided into two distinct stages: the first revolution of the workpiece and the subsequent revolutions. The governing vibration equations for each stage are derived separately. The first-stage equation is solved analytically, while the second-stage equation is solved using the semi-discretization method. Additionally, formulations for calculating the power and energy transmitted by the cutting force and dissipated due to system damping are presented. Through simulations, a comprehensive analysis of the system's vibrational behavior during the initial revolutions of the workpiece is conducted. The findings indicate that the system behavior during the first three revolutions, regardless of cutting width, is determined by the transient response in the first revolution caused by the tool feed. Furthermore, the results show that in the stable condition, the total power is zero; in the critically stable condition, it oscillates with a constant amplitude and a zero average value; and in the unstable condition, it oscillates with an increasing amplitude and a zero average value.This paper simulates workpiece vibrations in the orthogonal cutting process, from the initial engagement of the tool and workpiece, to conduct an in-depth investigation of chatter onset using an energy-based approach. For this purpose, the orthogonal cutting process of a disk is divided into two distinct stages: the first revolution of the workpiece and the subsequent revolutions. The governing vibration equations for each stage are derived separately. The first-stage equation is solved analytically, while the second-stage equation is solved using the semi-discretization method. Additionally, formulations for calculating the power and energy transmitted by the cutting force and dissipated due to system damping are presented. Through simulations, a comprehensive analysis of the system's vibrational behavior during the initial revolutions of the workpiece is conducted. The findings indicate that the system behavior during the first three revolutions, regardless of cutting width, is determined by the transient response in the first revolution caused by the tool feed. Furthermore, the results show that in the stable condition, the total power is zero; in the critically stable condition, it oscillates with a constant amplitude and a zero average value; and in the unstable condition, it oscillates with an increasing amplitude and a zero average value.https://jsfm.shahroodut.ac.ir/article_3743_1cbe3ecd415cb9446e93cdf2c5b8d05d.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122The effect of the presence of nanoclay and basalt fibers on the tensile and impact mechanical properties of PLA/NR polymer composites using the response surface method (RSM)The effect of the presence of nanoclay and basalt fibers on the tensile and impact mechanical properties of PLA/NR polymer composites using the response surface method (RSM)349365374410.22044/jsfm.2026.16447.3984FAMeysamNouri NiyarakiDepartment of Mechanical Engineering, Faculty of Aerospace Engineering, Shahid Sattari Aeronautical University, Tehran, IranAminBodaghiFaculty of Aerospace Engineering, Shahid Sattari Aeronautical University, Tehran, IranJournal Article20250630In this study, the effects of nanoclay and basalt fibers on the tensile and impact properties of PLA/NR polymer composites were experimentally investigated using the Response Surface Methodology (RSM). The studied variables included the weight percentage of nanoclay (0%, 3%, and 6%), basalt fibers (0%, 10%, and 20%), and natural rubber (0%, 15%, and 30%). The samples were prepared using an internal mixer and a hot press machine according to relevant standards. Tensile tests were conducted to determine tensile strength and elastic modulus, and Charpy impact tests were performed to evaluate impact strength. The results indicated that increasing the weight percentage of nanoclay at low concentrations improved tensile strength and elastic modulus by 10% and 21%, respectively, while higher percentages led to a reduction in mechanical properties. The addition of basalt fibers enhanced tensile strength, elastic modulus, and impact strength by 14%, 37%, and 39%, respectively. Increasing the natural rubber content resulted in a 44% improvement in impact strength but an 11% and 23% decrease in tensile strength and elastic modulus, respectively. Scanning electron microscopy (SEM) images were also used to analyze the dispersion of nanoparticles and basalt fibers within the polymer matrix.In this study, the effects of nanoclay and basalt fibers on the tensile and impact properties of PLA/NR polymer composites were experimentally investigated using the Response Surface Methodology (RSM). The studied variables included the weight percentage of nanoclay (0%, 3%, and 6%), basalt fibers (0%, 10%, and 20%), and natural rubber (0%, 15%, and 30%). The samples were prepared using an internal mixer and a hot press machine according to relevant standards. Tensile tests were conducted to determine tensile strength and elastic modulus, and Charpy impact tests were performed to evaluate impact strength. The results indicated that increasing the weight percentage of nanoclay at low concentrations improved tensile strength and elastic modulus by 10% and 21%, respectively, while higher percentages led to a reduction in mechanical properties. The addition of basalt fibers enhanced tensile strength, elastic modulus, and impact strength by 14%, 37%, and 39%, respectively. Increasing the natural rubber content resulted in a 44% improvement in impact strength but an 11% and 23% decrease in tensile strength and elastic modulus, respectively. Scanning electron microscopy (SEM) images were also used to analyze the dispersion of nanoparticles and basalt fibers within the polymer matrix.https://jsfm.shahroodut.ac.ir/article_3744_ce528f29674c36a8967e5343acf2ddc4.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122The Effect of Forming Diameter and Rotational Speed on Characterization of Formed Tubes by Spinning ProcessThe Effect of Forming Diameter and Rotational Speed on Characterization of Formed Tubes by Spinning Process367376371210.22044/jsfm.2025.16131.3969FAFarshadNazariDepartment of Mechanical Engineering, Shahid Chamran University of Ahvaz, Ahvaz, IranAlirezaSaadatiDepartment of Mechanical Engineering, Shahid Chamran University of Ahvaz, Ahvaz, IranMohammadBalaghi InalooDepartment of Mechanical Engineering, Shahid Chamran University of Ahvaz, Ahvaz, IranJournal Article20250506The spinning process is a common forming process used in the production of various products. It involves shaping sheets and tubes to create industrial products and sizing the connections in tubes. The purpose of this research is to investigate the effects of the final forming diameter and rotational speed on the twist angle, microstructure, hardness, strength, and the weldability in the spinning process of tubes. The spinnig process was analytically and experimentally evaluated, and the results were investigated using ANOVA analysis. The experiments were conducted using three different diameters and rotational speeds, and the response surface method was used to design the experiments. The analysis of the results revealed that the final forming diameter, or plastic strain, has a significantly greater effect on the mechanical properties and microstructure of the material compared to the rotational speed. An increase in rotational speed and forming diameter leads to a greater twist angle in the tubes. Higher rotational speeds and plastic strain result in increased contact and frictional forces, which cause the temperature to rise within the specimens. Increasing temperature results in grain growth, reduced work hardening, and consequently, a decrease in the material's strength and hardness. At a constant speed, a 25% increase in diameter results in a 47% decrease in hardness and strength. Additionally, using a rotational speed of 1000 rpm and a final diameter of 18 mm can increase the grain size up to three times the initial value and produce a maximum twist angle of 48⁰ in the sample.The spinning process is a common forming process used in the production of various products. It involves shaping sheets and tubes to create industrial products and sizing the connections in tubes. The purpose of this research is to investigate the effects of the final forming diameter and rotational speed on the twist angle, microstructure, hardness, strength, and the weldability in the spinning process of tubes. The spinnig process was analytically and experimentally evaluated, and the results were investigated using ANOVA analysis. The experiments were conducted using three different diameters and rotational speeds, and the response surface method was used to design the experiments. The analysis of the results revealed that the final forming diameter, or plastic strain, has a significantly greater effect on the mechanical properties and microstructure of the material compared to the rotational speed. An increase in rotational speed and forming diameter leads to a greater twist angle in the tubes. Higher rotational speeds and plastic strain result in increased contact and frictional forces, which cause the temperature to rise within the specimens. Increasing temperature results in grain growth, reduced work hardening, and consequently, a decrease in the material's strength and hardness. At a constant speed, a 25% increase in diameter results in a 47% decrease in hardness and strength. Additionally, using a rotational speed of 1000 rpm and a final diameter of 18 mm can increase the grain size up to three times the initial value and produce a maximum twist angle of 48⁰ in the sample.https://jsfm.shahroodut.ac.ir/article_3712_de54e1f03c4e8b150b59608376c72ff6.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Computational Study of the Effect of Torsional Loading on the Behavior of Nitinol Stents in the Femoropopliteal ArteryComputational Study of the Effect of Torsional Loading on the Behavior of Nitinol Stents in the Femoropopliteal Artery377394371310.22044/jsfm.2025.16437.3983FABahramEskiniArak University,Arak,IranMojtabaZolfaghariArak University,Arak,IranFardinNematzadehNanotechnology and Advanced Materials Department, Materials and Energy Research Center (MERC), Karaj, Iran, P.O. Box 316-31787, Tel (Fax):(+98)2636201888AryanEskiniArak University,Arak,IranJournal Article20250628Smart stents made from the shape memory alloy Nitinol are expanding in the medical field due to their unique properties, including temperature-dependent shape change and superelasticity. Predicting the behavior of these stents prior to fabrication can significantly reduce surgical and therapeutic risks and improve treatment processes. This study investigates and predicts the behavior of three types of stents (Smart Flex, Tigris, Viabahn) using the finite element analysis method. The analyses were conducted under torsion loading and at appropriate temperatures to examine superelastic behavior. The results obtained from the Auricchio model, used to describe the material properties of Nitinol in the Abaqus software, showed that the Flex Smart stent performed best in terms of Effective strain (0.05889), displacement (0.04943 m), stress (528.4 Pa), low force (266.9 N), Percentage of martensite (0.8001), and a large hysteresis loop (radial and circumferential force). The simulation results also revealed that the Smart Flex stent had the highest amount of twist and torsional moment (4.652 Nm), outperforming the other two models (Tigris & Viabahn). In the evaluation of simulation results and comparative analysis between the Tigris, Flex Smart, and Viabahn stents under torsional loading, the Tigris stent demonstrated the highest agreement with experimental results, with a difference of 23.22%. In contrast, the Smart Flex and Viabahn stents showed lower conformity with experimental data, with differences of 34.78% and 57.71%, respectively.Smart stents made from the shape memory alloy Nitinol are expanding in the medical field due to their unique properties, including temperature-dependent shape change and superelasticity. Predicting the behavior of these stents prior to fabrication can significantly reduce surgical and therapeutic risks and improve treatment processes. This study investigates and predicts the behavior of three types of stents (Smart Flex, Tigris, Viabahn) using the finite element analysis method. The analyses were conducted under torsion loading and at appropriate temperatures to examine superelastic behavior. The results obtained from the Auricchio model, used to describe the material properties of Nitinol in the Abaqus software, showed that the Flex Smart stent performed best in terms of Effective strain (0.05889), displacement (0.04943 m), stress (528.4 Pa), low force (266.9 N), Percentage of martensite (0.8001), and a large hysteresis loop (radial and circumferential force). The simulation results also revealed that the Smart Flex stent had the highest amount of twist and torsional moment (4.652 Nm), outperforming the other two models (Tigris & Viabahn). In the evaluation of simulation results and comparative analysis between the Tigris, Flex Smart, and Viabahn stents under torsional loading, the Tigris stent demonstrated the highest agreement with experimental results, with a difference of 23.22%. In contrast, the Smart Flex and Viabahn stents showed lower conformity with experimental data, with differences of 34.78% and 57.71%, respectively.https://jsfm.shahroodut.ac.ir/article_3713_212f18dd8c7870641ff53f83a889e157.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Effect of Travel Speed on CK45 Steel Welding: A Comprehensive Analysis of Mechanical Properties, Corrosion Behavior, Energy Input, and Processing TimeEffect of Travel Speed on CK45 Steel Welding: A Comprehensive Analysis of Mechanical Properties, Corrosion Behavior, Energy Input, and Processing Time411425371410.22044/jsfm.2025.16493.3991FASayyed MohammadreazSedehiSchool of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, IranAli REzaAriaeyMasoudJafarpourFaculty of Materials Engineering, Sirjan Azad University, Sirjan, IranZahraMolavi DosanganiFaculty of Mechanical Engineering, University of Guilan, Guilan, IranAlisinaMortezaei MoghadamDepartment of Mechanical Engineering, Isfahan University of Technology, Isfahan, IranJournal Article20250712This study investigates the effect of hand travel speed in manual arc welding using E6013 electrodes on the microstructural, mechanical, and corrosion properties of welds on CK45 steel. Welding was performed at five different speeds (17, 20, 26, 32, and 39 cm/min) in the flat position. Various tests, including Vickers hardness, potentiodynamic corrosion, XRD analysis (for crystallite size and microstrain), and OCP analysis were conducted. The results indicated that the 26 cm/min speed yielded the best overall performance, with the lowest microstrain (0.0021), smallest crystallite size (68 nm), and highest hardness (265 HV). Although the corrosion rate was moderate at this speed (0.0079 mm/year), structural stability and uniform phase distribution were evident. The highest corrosion rate occurred at 17 cm/min (0.022 mm/year), and the lowest at 39 cm/min (0.021 mm/year), though the latter showed the lowest hardness (186 HV). From a practical standpoint, welding at the intermediate speed offered optimal performance in terms of time, energy consumption, and defect minimization. This study highlights the critical role of travel speed in achieving a balance between mechanical performance, corrosion resistance, and process efficiency in manual weldingThis study investigates the effect of hand travel speed in manual arc welding using E6013 electrodes on the microstructural, mechanical, and corrosion properties of welds on CK45 steel. Welding was performed at five different speeds (17, 20, 26, 32, and 39 cm/min) in the flat position. Various tests, including Vickers hardness, potentiodynamic corrosion, XRD analysis (for crystallite size and microstrain), and OCP analysis were conducted. The results indicated that the 26 cm/min speed yielded the best overall performance, with the lowest microstrain (0.0021), smallest crystallite size (68 nm), and highest hardness (265 HV). Although the corrosion rate was moderate at this speed (0.0079 mm/year), structural stability and uniform phase distribution were evident. The highest corrosion rate occurred at 17 cm/min (0.022 mm/year), and the lowest at 39 cm/min (0.021 mm/year), though the latter showed the lowest hardness (186 HV). From a practical standpoint, welding at the intermediate speed offered optimal performance in terms of time, energy consumption, and defect minimization. This study highlights the critical role of travel speed in achieving a balance between mechanical performance, corrosion resistance, and process efficiency in manual weldinghttps://jsfm.shahroodut.ac.ir/article_3714_516a54e21e411b57398fb32b943a1bdc.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Effect of Oxygen Enriched Air Combined With EGR on Performance Parameters and Diesel Engine EmissionsEffect of Oxygen Enriched Air Combined With EGR on Performance Parameters and Diesel Engine Emissions427442370910.22044/jsfm.2025.15841.3950FAJavadKhademUniversity of BirjandMoslemAyubi RadUniversity of BirjandAliAsadiBozorgmehr University of Qaenat, Qaen, Iran.Seyed ImanPoormusaviUniversity of Birjand,
Birjand, IranJournal Article20250311In this study, the combined effect of oxygen enrichment and exhaust gas recirculation (EGR) on combustion performance and pollutant formation in a direct-injection diesel engine was investigated. The main objective was to analyze the simultaneous influence of increased oxygen concentration and EGR application on improving the combustion process and reducing exhaust emissions. Numerical simulations were conducted using AVL-FIRE software on an AVL 5402 single-cylinder, four-stroke, direct-injection diesel engine. The Shell ignition model and the Zeldovich NOx model were employed to predict temperature, pressure, soot, and NOx emissions, and the results were validated against experimental in-cylinder pressure data. The results show that the desired NO output is achieved at 1400 rpm using 21.5 to 22.5% oxygen enrichment and 5 to 10 percent EGR, and at 1800 rpm using 21 to 22% oxygen enrichment and 10 to 15% EGR. Also, in the case of using cold exhaust EGR, the desired NO can be achieved under 1400 rpm conditions using 21.5 to 22.5% oxygen enrichment and 10 to 15% EGR, and at 1800 rpm engine speed using 21 to 22% oxygen enrichment and 15 to 20% EGR.In this study, the combined effect of oxygen enrichment and exhaust gas recirculation (EGR) on combustion performance and pollutant formation in a direct-injection diesel engine was investigated. The main objective was to analyze the simultaneous influence of increased oxygen concentration and EGR application on improving the combustion process and reducing exhaust emissions. Numerical simulations were conducted using AVL-FIRE software on an AVL 5402 single-cylinder, four-stroke, direct-injection diesel engine. The Shell ignition model and the Zeldovich NOx model were employed to predict temperature, pressure, soot, and NOx emissions, and the results were validated against experimental in-cylinder pressure data. The results show that the desired NO output is achieved at 1400 rpm using 21.5 to 22.5% oxygen enrichment and 5 to 10 percent EGR, and at 1800 rpm using 21 to 22% oxygen enrichment and 10 to 15% EGR. Also, in the case of using cold exhaust EGR, the desired NO can be achieved under 1400 rpm conditions using 21.5 to 22.5% oxygen enrichment and 10 to 15% EGR, and at 1800 rpm engine speed using 21 to 22% oxygen enrichment and 15 to 20% EGR.https://jsfm.shahroodut.ac.ir/article_3709_3f59d1ab8ba25ed4df45d76d57a7e8d4.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Effect of Geometric and Thermophysical Properties of Porous Medium on Thermal Performance of a Finned Microchannel Heat SinkEffect of Geometric and Thermophysical Properties of Porous Medium on Thermal Performance of a Finned Microchannel Heat Sink443456371010.22044/jsfm.2025.15967.3953FASomayehDavoodabadi FarahaniMechanical Engineering Department, Arak University of Technology, Arak, IranAlirezaAlibigieghdArak University of Technology, Arak, IranJournal Article20250327This study numerically and three-dimensionally investigates the thermal performance of a microchannel heat sink integrated with a porous medium. Three different microchannel geometries—including square, circular, and finned—are considered, with conductive heat transfer modeled in the solid regions. Numerical simulations are performed using ANSYS Fluent . The Reynolds number range in this study is between 50 and 1000, representing laminar flow conditions.The effects of a newly designed porous fin, variations in microchannel geometry, heat flux distribution, porosity, Darcy number, and the ratio of solid to fluid thermal conductivity within the porous medium on the thermal performance of the microchannel heat sink are evaluated. Results indicate that the square microchannel heat sink exhibits superior thermal performance compared to other geometries. The thermal performance of the system is directly influenced by the spatial distribution of heat flux on the active surface, which plays a key role in enhancing heat transfer.<br />Furthermore, the use of porous fins improves the thermal performance of the microchannel heat sink, with the degree of enhancement depending on porous medium properties such as porosity, Darcy number, and the thermal conductivity ratio. Among these, the thermal conductivity ratio of the porous medium significantly affects system performance. Notably, employing a porous medium with porosity varying as a function of position along the flow direction (z-axis) can improve thermal performance by approximately 38%. This study clearly demonstrates that variations in porous medium characteristics, especially porosity and thermal conductivity, can have substantial impacts on the thermal performance of microchannel heat sink systems.This study numerically and three-dimensionally investigates the thermal performance of a microchannel heat sink integrated with a porous medium. Three different microchannel geometries—including square, circular, and finned—are considered, with conductive heat transfer modeled in the solid regions. Numerical simulations are performed using ANSYS Fluent . The Reynolds number range in this study is between 50 and 1000, representing laminar flow conditions.The effects of a newly designed porous fin, variations in microchannel geometry, heat flux distribution, porosity, Darcy number, and the ratio of solid to fluid thermal conductivity within the porous medium on the thermal performance of the microchannel heat sink are evaluated. Results indicate that the square microchannel heat sink exhibits superior thermal performance compared to other geometries. The thermal performance of the system is directly influenced by the spatial distribution of heat flux on the active surface, which plays a key role in enhancing heat transfer.<br />Furthermore, the use of porous fins improves the thermal performance of the microchannel heat sink, with the degree of enhancement depending on porous medium properties such as porosity, Darcy number, and the thermal conductivity ratio. Among these, the thermal conductivity ratio of the porous medium significantly affects system performance. Notably, employing a porous medium with porosity varying as a function of position along the flow direction (z-axis) can improve thermal performance by approximately 38%. This study clearly demonstrates that variations in porous medium characteristics, especially porosity and thermal conductivity, can have substantial impacts on the thermal performance of microchannel heat sink systems.https://jsfm.shahroodut.ac.ir/article_3710_80690f48d17b9a7062178732d0845690.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Numerical Investigation of the Effect of Height Ratio, Collector Angle, and Obstacle Presence in a Solar Chimney with a Two-Level InletNumerical Investigation of the Effect of Height Ratio, Collector Angle, and Obstacle Presence in a Solar Chimney with a Two-Level Inlet457474370810.22044/jsfm.2025.15217.3908FAMehdiMehdi Zadeh BalaniChabahar Maritime university, chabaharSeyedaminHosseiniChabahar Maritime UniversityMohammad RezaNegahdariچابهار دانشگاه دریانوردی و علوم دریایی گروه مهندسی دریاJournal Article20241021Among renewable energies, solar energy stands out as one of the best sources for human use due to its easy accessibility across the globe. This study focuses on the investigation of the shape and dimensions of solar chimney power plants, which are one of the methods for converting solar energy into electricity. Recently, the use of solar chimneys with a two-story collector has become a hot topic; thus, this optimization was performed on a solar chimney power plant with a two-story collector in two phases using numerical simulations in ANSYS Fluent. The optimization was conducted in such a way that in the first phase, the flow type in the two stories of the collector, which can be either co-flow or counter-flow, was optimized along with the height ratio of the two stories. In the second phase, the angle of the roof of the collector was optimized. The results indicate that when the flow in the two stories of the collector is co-flow, the power output of the plant is significantly higher. Additionally, in this case, when the height ratio of the first story to the total is set at 80%, the maximum efficiency and power output are achieved, measuring 1.22 and 39.5 kW, respectively. Analyzing the effect of the collector roof angles reveals that when the roof of the first story is horizontal and the roof of the second story has a one-degree angle, the power output and efficiency of the plant reach their optimal state.Among renewable energies, solar energy stands out as one of the best sources for human use due to its easy accessibility across the globe. This study focuses on the investigation of the shape and dimensions of solar chimney power plants, which are one of the methods for converting solar energy into electricity. Recently, the use of solar chimneys with a two-story collector has become a hot topic; thus, this optimization was performed on a solar chimney power plant with a two-story collector in two phases using numerical simulations in ANSYS Fluent. The optimization was conducted in such a way that in the first phase, the flow type in the two stories of the collector, which can be either co-flow or counter-flow, was optimized along with the height ratio of the two stories. In the second phase, the angle of the roof of the collector was optimized. The results indicate that when the flow in the two stories of the collector is co-flow, the power output of the plant is significantly higher. Additionally, in this case, when the height ratio of the first story to the total is set at 80%, the maximum efficiency and power output are achieved, measuring 1.22 and 39.5 kW, respectively. Analyzing the effect of the collector roof angles reveals that when the roof of the first story is horizontal and the roof of the second story has a one-degree angle, the power output and efficiency of the plant reach their optimal state.https://jsfm.shahroodut.ac.ir/article_3708_6ad9f0bd8e602350f314900a35bf473f.pdfShahrood University of TechnologyJournal of Solid and Fluid Mechanics2251-947515520251122Experimental and Numerical Investigation of the Effect of Blast Loading on Sandwich Structures with Metallic Lattice CoresExperimental and Numerical Investigation of the Effect of Blast Loading on Sandwich Structures with Metallic Lattice Cores371110.22044/jsfm.2025.16062.3960FAAliKoochakinejad EramsadatiPh.D. Student, Department of Mechanical Engineering, Islamic Azad University, Tehran, IranAliAlinia-ziaziFaculty of Mechanics, Electrical Power and Computer
Islamic Azad University, Science and Research BranchHashemBabaeiFaculty of Mechanical Engineering, University of Guilan, Rasht, IranShahramEtemadi HaghighiAssistant Professor, Department of Mechanical Engineering, Islamic Azad University, Tehran, IranMojtabaZiya-ShamamiAssistant Professor, Faculty of Engineering, Imam Hossein University, Tehran, IranJournal Article20250411Sandwich structures with metallic lattice cores, due to their lightweight and high strength, are widely used in aerospace, automotive, and dynamic load-resistant structures. In this research, the effect of blast loading on sandwich structures with trapezoidal and triangular lattice cores has been investigated both experimentally and numerically. Experimental tests were conducted using the free-air explosion method, and the mechanical response of these structures, including deformation and energy absorption, was analyzed. For numerical simulation, Abaqus software and the CONWEP method were used to model the blast effects. The results indicate that the geometry of the lattice core significantly influences the mechanical behavior of the sandwich structure. Trapezoidal and triangular lattice cores exhibit nearly similar behavior in terms of energy absorption and back face sheet deflection under blast loading. A comparison of experimental and numerical data demonstrates the high accuracy of the numerical model in predicting the structural behavior. The findings of this research can be utilized in the optimal design of blast-resistant structures.Sandwich structures with metallic lattice cores, due to their lightweight and high strength, are widely used in aerospace, automotive, and dynamic load-resistant structures. In this research, the effect of blast loading on sandwich structures with trapezoidal and triangular lattice cores has been investigated both experimentally and numerically. Experimental tests were conducted using the free-air explosion method, and the mechanical response of these structures, including deformation and energy absorption, was analyzed. For numerical simulation, Abaqus software and the CONWEP method were used to model the blast effects. The results indicate that the geometry of the lattice core significantly influences the mechanical behavior of the sandwich structure. Trapezoidal and triangular lattice cores exhibit nearly similar behavior in terms of energy absorption and back face sheet deflection under blast loading. A comparison of experimental and numerical data demonstrates the high accuracy of the numerical model in predicting the structural behavior. The findings of this research can be utilized in the optimal design of blast-resistant structures.https://jsfm.shahroodut.ac.ir/article_3711_052557a932069f149705d33c11d273a4.pdf