EFFECTS ON SPOKE STRUCTURE OF NON-PNEUMATIC TIRES BY FINITE ELEMENT ANALYSIS

Juthanee Phromjan,Chakrit Suvanjumrat 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.5

Cause of the non-pneumatic tires (NPTs) which are recent manufacturing have a higher weight that increases energy consumption for driving vehicles with them. This paper then focused on their proper spoke structure. Six patterns of spoke aligning on the NPT circumference were proposed to reduce the NPT weight. The finite element analysis (FEA) of the NPTs based on static and dynamic approaches was performed to study the spoke reduction effects. One pattern of spoke alignments was experimentally performed in the stiffness testing. The tested NPT had been prepared by cutting spokes of the original NPT with the water jet cutting technique. The experimental results then confirmed the accuracy of FEA in reducing the NPT’s weight. It found that the average error of FEA was less than 0.30 %. Therefore, the uniform spoke alignment on the NPT circumference had been carried out to study the effect of spoke numbers on reducing NPT weight by FEA. In advance of NPT design and manufacture with optimal weight, the vertical stiffness equation of this NPT was proposed by two variables, the number, and thickness of the spoke. Furthermore, the stress happening on the spokes was represented as a function to evaluate the NPT performance during operation.

Influence of Spoke Parameters on Load Capacity of Non-Pneumatic Tires Using Orthogonal Study and Analysis of Variance

Weidong Liu,Changzheng Li,Qiushi Zhang 한국자동차공학회 2024 International journal of automotive technology Vol.25 No.2

This study aims to investigate the relationship between the static characteristics of non-pneumatic tires (NPTs) and spokedesign parameters using the fi nite element (FE) method. A three-dimensional FE model of the NPT was established. Theinfl uence of diff erent ranges of stress and strain on the calculation accuracy of the Neo-Hookean and Yeoh constitutivemodels was analyzed. Subsequently, the main design parameters—spoke thickness, spoke number, and arc curvature—wereselected according to the geometric characteristics of the spokes. The eff ects of these three parameters on the vertical stiff -ness, maximum spoke stress, overall maximum stress, and maximum and average contact pressures were examined usingunivariate and multivariate analysis methods. The range and variance analysis results indicated that the spoke thickness,spoke number, and arc curvature had a signifi cant eff ect on the vertical stiff ness. Finally, the relationship between the verticalstiff ness and product of the spoke thickness and number was obtained using a nonlinear fi tting method. When the arc curvatureof the spoke was less than 5 m −1 , the errors between the calculated and simulated vertical stiff ness did not exceed 5%. This observation can be used to facilitate the rapid design of spoke parameters under diff erent load capacity requirements.

Analysis of an Armature Reaction Effect in the case of a Special Spoke Type BLDC Motor using a Ferrite Permanent-Magnet

Chae Lim Jeong,Il Man Seo,Hyung Kyu Kim,Jin Hur 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

In this paper, we propose a design of a special spoke-type brushless direct current (BLDC) motor using a ferrite permanent magnet and an analysis of armature reaction effect for the special spoke-type motor. Firstly, we design the special spoke-type BLDC motor, considering its cogging torque to be improved, and adjust an angle between the permanent magnets. By changing the angle, it is helpful to concentrate the fluxes of the permanent magnets, thereby increasing the air-gap flux density. Secondly, an armature reaction effect in this special case motor is analyzed because the spoke-type motor is significantly affected by this effect as compared with surfaced permanent magnet type BLDC motor. Therefore, we analyze the effect of the armature reaction according to the mechanical load and the input current. The output performance of the special spoke-type motor and the armature reaction effect are verified through a finite element analysis and an experiment.

Hub-and-spoke 관광개발을 위한 Networks 분석-부산지역을 중심으로-

박경옥 ( Kyoung Ok Park ),김인신 ( In Sin Kim ),류지호 ( Ji Ho Ryu ) 대한관광경영학회 2014 觀光硏究 Vol.29 No.3

본 연구의 목적은 Hub-and-Spoke 관광개발개념을 적용하여, 부산지역에 위치한 관광지 간 균형 있는 발전을 위한 전략을 제시하는 것이다. 이러한 목적을 달성하기 위하여 첫째, 사회연결망분석(Social Network Analysis:SNA)을 활용하여 부산 방문객의 이동흐름을 분석하였으며 네트워크 구조와 관광지들의 결절지를 발견하였으며 둘째, 부산지역의 총 57개소 관광목적지를 행정구역 상 4개의 구역(A, B, C, 그리고 D구역)으로 나누어 구체적인 이동 네트워크 구조와 결절지를 분석하였다. 본 연구의 분석 결과는 첫째, 부산 전체 관광지 네트워크 구조의 연결중심성, 매개중심성 그리고 근접중심성에서 해운대 해수욕장이 관광객 이동 네트워크에서 가장 영향력이 있는 것으로 나타났으며, 해운대 해수욕장은 특히 자갈치 시장과 활발한 네트워크를 나타냈다. 둘째, 구역별로 살펴보면, 부산시의 네 개 구역 중 D구역(해운대해수욕장이 포함된 구역)과 B구역(자갈치시장 포함 구역)이 가장 강력한 네트워크를 형성하였다. 반면, B와 D구역은 다른 구역들(A, C)과는 다소 약하거나 아무런 상호작용도 하지 않았다. 이는 해운대해수욕장이 Hub 관광지로서 영향력을 발휘할 수 있는 관광지이지만, 이를 중심으로 지나치게 편중된 관광객 이동 네트워크를 형성하고 있음을 보여주었다. 이러한 결과를 바탕으로 부산 관광개발자들은 편중성이 심한 지역의 네트워크를 다른 관광지들과 연계할 수 있도록 실질적 전략의 수립이 요구된다. 이와 같은 연구결과를 바탕으로 학문적, 실무적 시사점이 논의되었다. The main purpose of this study was to suggest the well-proportioned development strategies of tourism destinations in Pusan, based on the Hub-and-spoke tourism development concept. To achieve this aim, (1) the structure of movement networks and the centrality of tourism destinations were analyzed through the data collected from 279 tourists in Pusan by using Social Network Analysis(SNA) that reveals the Degree, Between and Closeness Centrality. (2) the tourism destination including 57 attractions was divided into four zones, namely A, B, C and D, to analyze detailed movement networks. The results of analysis revealed two major findings: (1) a Heaundae beach had significant influences on all tourism destinations, especially a Jagalchimarket attraction and (2) D zone included a Heaundea beach had the strongest network with B zone included a Jagalchimarket attraction among four zones separated than A, C zones. Although the Heaundea beach could be considered one of the influential tourism destination such as Hub, the tourists` movement flowing was too much emphasis on the tourism destination in Pusan. Therefore, tourism development planers needed to plan a substantive strategy in connecting the visitors` movement network with the other destinations. The theoretical and managerial implications were discussed.

하이브리드 다중 Hub-and-Spoke 차량 경로 계획 모형

이용대(Yongdae Lee),정현종(Hyunjong Jeong),손영수(Young Soo Son),윤치환(Chiwhan Yoon) 한국경영과학회 2011 經營 科學 Vol.28 No.3

Hub-and-spoke transportation network is a powerful and useful network structure that takes full advantage of economies of scale on routes between hubs. In recent studies, the network structure is extended to hybrid hub-andspoke that allows direct transportation between spokes. In this study, we considered more extended network structure which is called hybrid multiple hub-and-spoke that has multiple hubs and allows direct transportation between spokes. We developed a mathematical optimization model for automotive service parts transportation planning under hybrid multiple hub-and-spoke network structure. The model suggests a long-term transportation route planning and a short-term vehicle assignment planning. The model is verified by simulation and validated in real world application to Hyundai Mobis automotive service parts transportation planning. From the simulation result, the model reduced the transportation cost about 24.7%, the total distance about 6.8% and the CO2 emissions about 8.8%. In real world application for 6 months from July to December 2010, the model reduced the transportation cost about 9.1% by changing the long-term transportation route without daily vehicle assignment planning.

The Effect of the Ratio of Remanent Flux Density to Coercivity of Magnet on Spoke-Type Permanent Magnet Synchronous Motor (PMSM) Performance

Minyeong Choi,Yang-Ki Hong,Hoyun Won,Shuhui Li,S. Rahman,M. Nurunnabi,Woncheol Lee,Chang-Dong Yeo 전력전자학회 2023 ICPE(ISPE)논문집 Vol.2023 No.-

Spoke-type PMSMs were designed with commercial permanent magnets and theoretically designed hexaferrite: Nd-Fe-B (NdFe35, G1NH), Alnico (8B, 8H, 9), and La-CoSrM hexaferrite (NMF-15G). It was found that coercivity (Hc) plays a crucial role in determining motor performance. The ANSYS Maxwell software was used to characterize the designed motor performance. Commercial RE-free Alnico 9 holds a 10.5 MGOe of (BH)<SUB>max</SUB>, much higher than a 5.5 MGOe of RE-free Alnico 8B/8H and SrM (SrFe<SUB>12</SUB>O<SUB>19</SUB>) hexaferrite magnets. However, the Alnico 9 motor performance is not better than the other Alnico 8B/8H and hexaferrite motors. The spoke-type PMSM with our theoretically designed SrM hexaferrite simulated motor performance. A motor performs best when the Hc/Br ratio equals one with a high Hc. For instance, the motor torque and peak power increase to 189 Nm and 178 kW, respectively, as the Hc increases to 4.86 kOe from 2.43 kOe. However, the motor performance is not significantly changed with a fixed Hc and various Br. It was found that regardless of (BH)<SUB>max</SUB>, coercivity (Hc) plays a dominant role in motor performance.

Incremental Optimization of Hub and Spoke Network under Changes of Spokes’ Number and Flow

Yanfeng Wang,Youfang Huang 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.1

Hub and spoke network has been widely used in air transport, road freight, shipping network and urban distribution areas as part of the strategic decisions, which may have a profound effect on the future of enterprises. In view of the existing network structure, as time goes on, the number of spokes and the flow change because of different sources of uncertainty. Hence, the incremental optimization of the capacitated single-allocation hub and spoke network problem is considered in this paper, and the decisions to be made to cope with change comprise (i) whether new hubs need to be setup and their selection, (ii) whether the capacity levels of original hubs need to be adjusted, and their new capacity levels, (iii) whether the original hubs need to be closed, (iv) the new allocation of the spoke nodes to the hubs, (v) the flow distribution through the sub network defined by all the hubs. The objective is to minimize the total cost, which includes the setup costs for the new hubs, the closure costs and the adjustment costs for the original hubs as well as the flow routing costs. Two mixed-integer linear programming formulations are proposed and analyzed for this problem. A set of computational tests are performed, and we analyze the changes in the solutions driven by the number of spokes and the flow. The tests also allow an analysis to consider the effect of variation in parameters on the network.

비공기압 타이어의 진동 개선방안에 대한 연구

정성필,박재현,마경업,정진선 대한기계학회 2019 大韓機械學會論文集A Vol.43 No.6

In this study, to improve the vibration characteristics of non-pneumatic tires, the mechanical characteristics of a honeycomb and straight spokes were compared and analyzed. It was proven that the amplitude of vibration can be reduced by inserting an insulator between the straight spoke and the wheel. By constructing finite element models for the honeycomb and straight spokes and performing a structural and the vibration analysis, the vertical stiffness and vibration characteristics of the straight spoke were confirmed to be better than those of the honeycomb spoke. A comparison of models before and after the insertion of the insulator into the straight spoke proved that the insulator does not affect the magnitude of the natural frequency; however, it reduces the amplitude of the vibration. 본 연구에서는 비공기압 타이어의 진동 특성을 개선하기 위하여 허니컴 스포크와 일자형 스포크의 기계적 특성을 비교 분석하였고, 일자형 스포크와 휠 사이에 절연체를 삽입함으로써 진동의 크기를 줄일 수 있음을 입증하였다. 허니컴 스포크와 일자형 스포크에 대한 유한요소 모델을 생성하여 구조 해석과 진동 해석을 수행함으로서 수직 강성 과 진동 특성이 일자형 스포크가 좋음을 확인하였다. 일자형 스포크에 절연체를 삽입하기 전/후 모델 비교를 통해 절연체 삽입이 고유 진동수의 크기에는 영향이 없으나, 진동의 크기(진폭)는 줄인다는 것을 증명하였다.

Numerical Analysis of Contra-Rotating Small Hydro-Turbine with Cylinder Spoke

Nan, Ding,Shigemitsu, Toru,Zhao, Shengdun,Takeshima, Yasutoshi Korean Society for Fluid machinery 2018 International journal of fluid machinery and syste Vol.11 No.1

Small hydropower is one of potential energy resource existing in our living environment and yet not been widely used. Small hydro-turbine is suitable in these energy resources while it still has some shortages, like performing low efficiency and easy to be out of control when there are foreign materials in the water. Thus we designed this contra-rotating small hydro-turbine to increase its efficiency and enhance its ability of keeping stable operation. The experimental apparatus was designed and assembled, and some experiments were conducted. A new kind of cylinder spoke, which supports the front and rear rotor, was adopted and the numerical analysis was carried out in this paper. As the numerical analysis results shown, the efficiency of test turbine with cylinder spoke increased in a wide range of flow rate. The maximum efficiency increased about 2.2%, reaching to 66.4%, and it was obtained at $1.25Q_d$. The internal flow condition, especially at the areas behind the spoke, was improved by the cylinder spoke.

Numerical Analysis of Contra-Rotating Small Hydro-Turbine with Cylinder Spoke

Ding Nan,Toru Shigemitsu,Shengdun Zhao,Yasutoshi Takeshima 한국유체기계학회 2018 International journal of fluid machinery and syste Vol.11 No.1

Small hydropower is one of potential energy resource existing in our living environment and yet not been widely used. Small hydro-turbine is suitable in these energy resources while it still has some shortages, like performing low efficiency and easy to be out of control when there are foreign materials in the water. Thus we designed this contra-rotating small hydro-turbine to increase its efficiency and enhance its ability of keeping stable operation. The experimental apparatus was designed and assembled, and some experiments were conducted. A new kind of cylinder spoke, which supports the front and rear rotor, was adopted and the numerical analysis was carried out in this paper. As the numerical analysis results shown, the efficiency of test turbine with cylinder spoke increased in a wide range of flow rate. The maximum efficiency increased about 2.2%, reaching to 66.4%, and it was obtained at 1.25Qd. The internal flow condition, especially at the areas behind the spoke, was improved by the cylinder spoke.