Optimasi Desain Struktur Train Nose Frame dengan Finite Element Analysis

Abstract

Abstrak. Pada penelitian ini dilakukan simulasi Ansys Static Structural 2020 R2 untuk menganalisis deformasi, nilai tegangan, dan optimasi dengan penentuan safety factor. Perancangan train nose dilakukan dengan menggunakan Computer-aided engineering (CAE), Autodesk Inventor 2023. Paduan aluminium alloy 6005 T5 digunakan sebagai material struktur train nose. Model ini dirancang berdasarkan truss structure sederhana. Structure truss memiliki ketebalan yang bervariasi, mulai dari 50 mm x 50 mm, 60 mm x 60 mm, 70 mm x 70 mm, 80 mm x 80 mm, 90 mm x 90 mm, 100 mm x 100 mm, dan 110 mm x 110 mm. mm. Metode uji pembebanan struktur statis menggunakan beberapa variasi, seperti pembebanan vertikal, kompresi, dan puntir. Vertikal loading test terdiri dari dua masinis, panel, dan pemberat maskara. Rumus perhitungan pembebanan vertikal didasarkan pada peraturan hukum JIS E 7105. Menurut JIS E 7105, beban tekan longitudinal harus dipertahankan oleh kereta api sebesar 400 kN dengan atau tanpa beban vertikal. Perhitungan pembebanan dengan uji kompresi yang dipilih adalah tanpa penumpang, atau hanya kompresi dan pembebanan vertikal. Analisis lainnya meliputi kompresi penumpang dan total vertical loading. Sedangkan metode beban puntir dilakukan dengan simulasi dengan mengangkat salah satu bantalan pendongkrak secara vertikal dengan beban seberat 4 ton. Nilai optimum didasarkan pada uji statis lainnya, seperti uji tegangan dengan nilai maksimum 108,18. Optimasi ulang dilakukan pada struktur penampang yang memiliki ukuran 110 mm x 110 mm. Simulasi menunjukkan bahwa pengurangan jumlah balok dilakukan pada sisi, atas, dan lantai struktur, namun dengan safety factor yang sama. Sedangkan struktur depan kereta diubah sedemikian rupa untuk mengurangi efek deformasi akibat beban kompresi yang diuji. Pada simulasi akhir didapatkan safety factor sebesar 2,3961 pada luasan 110 mm x 110 mm. Ini menunjukkan semakin besar struktur, semakin besar safety factor yang kita dapatkan. Dari simulasi terlihat bahwa safety factor semakin meningkat, dengan semakin besarnya luas area. Safety factor dapat ditentukan oleh ultimate stress dari material. Semakin kecil tegangan maksimum dari balok, semakin besar safety factor yang kita dapatkan.

Abstract. In this study, Ansys Static Structural 2020 R2 simulations were conducted to analyze deformation, stress value, and optimization with the safety factor determination. Design of the train nose was conducted using Computer-aided engineering (CAE) Autodesk Inventor 2023. Aluminum alloy-wrought 6005 T5 is used as a material for the structure of the train nose. The model is designed based on a simple truss structure. The truss structure has various thicknesses, starting from 50 mm x 50 mm, 60 mm x 60 mm, 70 mm x 70 mm, 80 mm x 80 mm, 90 mm x 90 mm, 100 mm x 100 mm, and 110 mm x 110 mm. The loading test method of static structure uses some variations, such as vertical, compression, and twisting load. The vertical loading test consists of two machinists, panels, and mascara weights. The formula calculation of vertical loading is based on the law regulation JIS E 7105 [8]. According to JIS E 7105, longitudinal compression loading must be kept by train at the value of 400 kN with or without vertical loading. The calculation of loading with the chosen compression test is with no passengers, or just compression and vertical loading. The other analysis includes passenger compression and total vertical loading. On the other hand, the method of twisting load is done by simulation by lifting one of the jacking pads vertically at the weight of 4 tons [8]. The optimum value is based on the other static test, such as the stress test with a maximum value of 108.18. Re-optimization is conducted on the structural cross-section which has a size of 110 mm x 110 mm. The simulation shows that the reduction in the number of beams is carried out on the sides, top, and floor of the structure, but with the same safety factor. Meanwhile, the front structure of the train is changed in such a way as to reduce the effect of deformation by the tested compression load. In the final simulation, we get the safety factor of 2.3961in the size of area 110 mm x 110 mm. It shows the bigger structure, the bigger the safety factor we get. From the simulation, we can see that the safety factor getting increases, with the bigger size area. The safety factor can be defined by the ultimate stress from the material. The smaller the maximum stress from the beam, the bigger the safety factor we get.