간행물
한국기계항공기술학회지(구 한국기계기술학회지) KCI 등재 Journal of the Korean Society of Mechanical and Aviation Technology
- 발행기관 한국기계기술학회
- 자료유형 학술지
- 간기 격월간
- ISSN 1229-604X (Print)2092-0385 (Online)
- 수록기간 1999 ~ 2026
- 주제분류 공학 > 기계공학 공학 분류의 다른 간행물
- 십진분류KDC 550DDC 620
권호리스트/논문검색
제27권 제6호 (2025년 12월) 34건
21.
2025.12
구독 인증기관 무료, 개인회원 유료
Photocurable polymer components fabricated via 3D printing often exhibit rough surfaces and visible layer marks due to the inherent characteristics of additive manufacturing. Consequently, post-processing is frequently required to improve the external appearance of the final product. Since surface finishing is typically performed through machining, the appropriate selection of machining parameters is critical to prevent thermal-induced surface damage, particularly given the low heat-deflection temperature of polymer materials. Moreover, the mechanical properties of photocurable resins vary depending on resin composition and curing conditions, which also affect machinability. Therefore, baseline machining experiments are necessary to determine the optimal post-processing conditions for printed components. In this study, machining experiments were conducted on polymer specimens fabricated using a DLP (Digital Light Processing) system by varying spindle speed, feed rate, and depth of cut to optimize surface finishing conditions. The results indicate that the most improved surface roughness, approximately Ra 0.4 μm, was achieved under the conditions of 20,000 RPM spindle speed, 60 mm/min feed rate, and 100 μm depth of cut. This represents a 14-fold improvement compared to the pre-machining surface roughness. These optimized conditions are expected to be applied to the post-processing of porous scaffold core molds in future work.
4,000원
22.
2025.12
구독 인증기관 무료, 개인회원 유료
This study explores the critical interrelationship between component standardization and airworthiness certification in the context of military aircraft systems. As the complexity and technological integration of modern defense platforms increase, the alignment between standardized component frameworks and evolving airworthiness requirements becomes essential to ensure operational reliability, safety, and maintainability. The current defense acquisition and certification systems often operate in a decoupled manner, leading to duplicated testing, certification delays, and cost overruns. Through comparative analysis of national and international certification protocols (MIL-HDBK-516, NATO STANAG, EASA SIB), this paper identifies structural inefficiencies in managing non-standardized or partially certified components. Based on these findings, the study proposes a function-based integrated management system that enables data synchronization across standard parts databases, quality records, and certification requirements. The proposed framework consists of four core modules: (1) standard part information management, (2) quality assurance and test linkage, (3) certification support engine, and (4) lifecycle risk monitoring. The study also anticipates quantifiable improvements such as reduced certification time and improved audit traceability. The results provide practical and policy implications for enhancing the interoperability, reliability, and export competitiveness of domestic defense platforms.
4,000원
23.
2025.12
구독 인증기관 무료, 개인회원 유료
Small VTOL platforms envisioned for Urban Air Mobility (UAM) require compact and high–disk-loading propulsion systems, for which coaxial propellers are a suitable option. While counter-rotating coaxial propellers have been widely studied due to their torque-cancellation advantages, combined experimental and CFD-based research on coaxial co-rotating systems remains limited. This study investigates the aerodynamic performance of such a system using RANS-based CFD simulations, complemented by parallel experiments for validation. A pair of 18-inch, two-bladed propellers was arranged in a stacked layout, with mounting angle and inter-rotor spacing treated as key design variables. Results indicate that rotor–rotor interference leads to a maximum Figure of Merit (FoM) of 0.51 when the upper rotor leads at H/D = 0.07 and index angle of +15°. Increasing axial spacing generally improves the performance of both the upper and lower rotors, with the maximum thrust of 17.5N obtained at H/D = 0.07 and +45°. These performance trends were confirmed experimentally, and differences between CFD predictions and measurements remained within 5% for thrust and 6% for torque, demonstrating strong agreement. This study identifies influential design parameters for coaxial co-rotating propeller systems and provides a validated numerical methodology, offering a useful foundation for future high-efficiency Electric Distributed Propulsion System (EDPS) development.
4,200원
24.
2025.12
구독 인증기관 무료, 개인회원 유료
As the widespread adoption of autonomous vehicles is anticipated, a greater diversity of occupant postures is expected. However, current vehicle safety systems are not adequately designed to accommodate these varied postures, particularly relaxed seating positions, in which severe injuries have been reported during frontal collisions. Therefore, it is essential to investigate the biomechanical responses and injury tolerances of occupants in relaxed postures. In this study, the head kinematics and injury responses of the Hybrid-III and THOR anthropomorphic test devices, as well as the THUMS human body model, in a relaxed posture are analyzed using frontal impact sled simulations equipped with the sled system model developed in the previous study. The simulation results are evaluated through comparison with post-mortem human surrogate data. The findings of this study are expected to contribute to the fundamental design of new head restraint systems for human heads in autonomous vehicles.
4,000원
25.
2025.12
구독 인증기관 무료, 개인회원 유료
This study investigates the dynamic characteristics of telescopic booms for special-purpose vehicles fabricated with giga-grade ultra-high strength steel (UHSS) plates that have been increasingly adopted in industrial applications. In thin-walled structures such as telescopic booms, dynamic properties – particularly natural frequencies – are critical factors directly related to structural safety. Accordingly, the dynamic characteristics were experimentally measured and analyzed for identically designed booms fabricated using either imported giga-grade steel (Strenx 960) or domestic giga-grade steel (ATOS 980), both of which are widely available in the domestic market. The natural frequencies were identified based on frequency response functions (FRFs), and the corresponding mode shapes were obtained through experimental modal analysis. The results show that the nominal yield and tensile strengths provided by the manufacturers and the measured natural frequencies and mode shapes exhibit highly similar characteristics. These experimental findings confirm that the domestic UHSS exhibits a level of dynamic performance comparable to that of the imported steel of the same grade. Consequently, the results support the feasibility of applying domestic giga-grade UHSS to telescopic boom structures and highlight its potential contribution to material localization and enhanced design competitiveness in the domestic special-purpose vehicle industry.
4,000원
26.
2025.12
구독 인증기관 무료, 개인회원 유료
This study compares the shear behavior of anisotropic magnetorheological elastomers (MREs) using natural rubber (NR) and silicone rubber (Si) as matrices. The effects of magnetic flux density and compressive pre-stress on the shear modulus were experimentally investigated. Results showed that silicone-based MREs exhibited a 10–20% higher magnetorheological effect than NR-based ones due to stronger particle–matrix bonding and stable chain alignment under magnetic fields. In contrast, NR-based MREs showed greater stiffness variation under compressive stress, attributed to strain-hardening and volumetric constraint effects. These findings indicate that matrix selection significantly governs the magneto-mechanical response: silicone MREs are suitable for precision control and sensing, while NR MREs perform better in high-stress damping systems. This study provides fundamental insight for tailoring MREs according to design requirements.
4,000원
27.
2025.12
구독 인증기관 무료, 개인회원 유료
This study examines the influence of the number of orifice stages on flow characteristics using Computational Fluid Dynamics (CFD). Transient simulations were conducted with one to four stages under identical boundary conditions, employing the SST turbulence model. The results show that outlet pressure and pressure hunting behaviors are strongly dependent on the stage number. Single- and two-stage models exhibited periodic pressure oscillations, whereas three- and four-stage models demonstrated irregular or stabilized patterns, with the four-stage configuration achieving the lowest pressure hunting. The maximum velocity increased with the number of stages, with peak values observed at the orifice sections. Similarly, eddy viscosity intensified as the number of stages increased, indicating enhanced turbulent mixing. These findings highlight that the number of orifice stages plays a critical role in determining pressure stability and flow behavior, providing useful insights for the optimal design of orifice-based flow control systems.
4,000원
28.
2025.12
구독 인증기관 무료, 개인회원 유료
In the present analysis study, an analysis model was developed using ANSYS Workbench to verify the dynamic characteristics of the cabinet and the vibration reduction effect of applying TMD. The analysis modeled a simplified equivalent structure of a nuclear power plant cabinet, and a method was explored to reduce the cabinet's resonant response by installing TMD on top of the cabinet. For the analysis, harmonic loads and SSE seismic waves were input to conduct modal analyses of the cabinet and TMD. The cabinet vibration reduction effect of TMD installation was investigated, as well as the time histories of displacement and acceleration. The analysis results showed that the primary mode of the cabinet had a MPMR of approximately 53.9%, significantly affecting the dynamic behavior of the cabinet compared to other modes. However, a MPMR of approximately 8.9% was also observed in higher-order modes. With TMD installed, the peak response was significantly reduced, the larger curve split into two smaller curves, and the response at the original natural frequency was reduced by up to approximately 60%. The cabinet's time response showed a decrease in displacement/acceleration vibration response as the damping ratio increased. This indicates a narrow bandwidth and peak suppression of the response envelope, and the maximum displacement and acceleration reduction effects were approximately 33.1% and 27%, respectively.
4,000원
29.
2025.12
구독 인증기관 무료, 개인회원 유료
This study investigates the thermo-mechanical behavior and residual stress characteristics of friction stir welding (FSW) in an aluminum inverter housing using finite element analysis (FEA). FSW experiments were first conducted under various tool rotation and traverse speed conditions, and temperature histories were measured using K-type thermocouples. The optimal process condition was identified through tensile testing, and the heat input was estimated by comparing experimental and numerical results. The estimated heat source was incorporated into a transient thermal elasto-plastic analysis to evaluate deformation and residual stresses in an inverter housing model. The results indicated that residual stress distributions varied depending on the welding start position. In particular, when welding started at P3 (near thick ribs and bosses) residual stresses were reduced by approximately 30% compared to P1, owing to the higher local stiffness and enhanced heat dissipation that mitigated temperature gradients. Conversely, welding initiated at P1, a flat region with insufficient reinforcement, resulted in higher stress concentrations. These findings confirm that the welding start position significantly influences residual stress behavior in inverter housings and provide fundamental insights for developing residual stress control strategies in FSW of large-scale components.
4,200원
30.
2025.12
구독 인증기관 무료, 개인회원 유료
The purpose of this study is to develop an electroless nickel plating process suitable for IXEF 1022, which is a high-performance polymer, and to analyze the effect of plating temperature on plating quality in particular. The experiment was conducted at 80°C, 83°C, and 85°C, and as a result, it was confirmed that as the temperature increased, the thickness and external dimensions of the plating layer gradually increased, and the plating layer tended to be uniformly formed on the entire surface. In addition, the adhesion and quality of the plating layer were maintained stably even at high temperatures, which proves the practicality and reliability of the process. These results contribute to the improvement of the conductivity and durability of IXEF 1022, and suggest the possibility of application in various industrial fields such as electronics, automobiles, and medical devices.
4,000원
31.
2025.12
구독 인증기관 무료, 개인회원 유료
With the rapid transition to an aging society, the need for assistive technologies that promote independent indoor living for the elderly and mobility-impaired has become increasingly critical. This study proposes the development of a next-generation powered chair designed to support such independence by compensating for mobility limitations caused by natural aging. The proposed system incorporates two core functionalities: (1) an low seat-lifting mechanism capable of lowering the seat height to 7 cm, and (2) a short-range autonomous driving mode operable in both lowered and lifted positions. The low driving mode enables the user to approach low tables or desks and facilitates effortless transfer to and from low beds or sofas. In the lifted position, the system performs real-time obstacle detection and avoidance within a 3-meter range, preventing falls and collisions while expanding the user’s range of motion— for instance, by allowing access to higher objects or enabling eye-level communication with standing individuals. To realize these functions, a rack-and-pinion lifting mechanism is applied, along with a direct target-point designation method utilizing an LED pointer and a wiper-type screening approach for real-time obstacle avoidance. The design concept, implementation strategy, and validation plan are presented. This research contributes to enhancing the quality of life for elderly users by maximizing their remaining physical capabilities, while simultaneously reducing the physical and emotional burden on caregivers.
4,000원
32.
2025.12
구독 인증기관 무료, 개인회원 유료
The fabrication of curved hull plates is a critical process in shipbuilding, affecting both the structural integrity and hydrodynamic performance of vessels. This study investigates a hybrid forming method that combines induction heating and multi-point press forming to improve the accuracy and efficiency of curved plate production. The forming experiments were performed under various heating and pressing conditions to examine their effects on deformation behavior, forming accuracy, and surface quality. The results indicate that the hybrid forming approach effectively reduces processing time, minimizes spring-back, and enhances the precision of the formed geometry compared with conventional mechanical forming. These findings demonstrate the potential of hybrid forming as an efficient and reliable technique for manufacturing complex hull structures in modern shipbuilding.
4,000원
33.
2025.12
구독 인증기관 무료, 개인회원 유료
This paper was studied to improve the efficiency of big fans through the modification of the impeller shape while maintaining other parameters such as casing geometry(shape), entry and exit diameter, rotation speed, number of blades, flow rate, and static pressure in accordance with the field requirements including the existing installation. Numerical calculation based on semi-empirical formula(SEF) and the methodology of computational fluid mechanics(CFD) were used. It is widely used in the chemical industry, and a large fan with a nominal flow capacity of 510,000 m/h and a static pressure of 11,000 Pa was used as a case study. In this study, the theoretical performance comparison and field measurements of the existing fan and crystal fan geometry designs were conducted. The results of the study showed that the modified geometric design can contribute to reducing the absorption power by up to 135 kW, thereby increasing the fan efficiency by up to 5.87%.
4,000원
34.
2025.12
구독 인증기관 무료, 개인회원 유료
Injection molds, composed of components such as upper and lower cores, mold bases, pins, and cooling channels, serve as the primary tooling for manufacturing plastic products. Despite the often simple geometry of molded products, the configuration and design of mold components remain highly complex, making the technical expertise and accumulated know-how of mold designers essential. However, the mold industry is facing increasing difficulties due to the discontinuation of academic programs dedicated to mold design, the aging of experienced designers, and the lack of incoming skilled personnel. To address these challenges, research on automating mold design has continued, and recent advancements in artificial intelligence (AI) have accelerated efforts to internalize expert knowledge through a variety of computational approaches. In this study, we conducted foundational research aimed at constructing a DT-AX platform capable of handling multiple domains by implementing and modularizing diverse processes within a digital-twin (DT) environment and integrating AI modules specialized for each process. Given the input dimensions of a bottle-cap model (diameter and height), the simplified outer dimensions of a core mold were predicted and subsequently used to generate a 3D model. The resulting STEP file was verified to be compatible with commercial CAD and simulation software. Overall, the results demonstrate the feasibility of implementing an automated mold-design module within a digital-twin environment. Future work will focus on diversifying design variables and increasing geometric complexity to develop modules that more closely approximate real-world mold design.
4,000원
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