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Failure Prediction of Cracked Pressure Vessel under Fatigue Load Based on API 579 Standard and Finite Element Method Akbar, Musthafa
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 37 No 1 (2016): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36842/jomase.v37i1.397

Abstract

Failure prediction of cracked pressure vessel is analyzed based on crack growth behavior under fatigue loading. The major objective of this study was to investigate and validate the use of commonly used industry standard with finite element method in order to predict failure of cracked pressure vessel. Growing of crack due to fatigue load was analyzed using both analytical and finite element method. In analytical side, API 579 Code is used with involving safety and correction factor which will increase conservatism degree of the results. Pressure vessel with D/t ratio 40, 60, and 80 were taken into analysis. Semi elliptical cracks in longitudinal and circumferential position were included into analysis with ratio a/t=0.3, 0.5, 0.8 and a/c=0.15, 0.125, 0.1. In this paper, there are 84 numerical model were solved numerically and plotted into several curves. Comparisons between API 579 and finite element simulation show that pressure vessel with D/t=40, 60 and 80 have percent error about 2.16 %, 9.32 % and 10.57 %, respectively. This results are reasonable due to several safety factor are included in API 579 analysis. Results of this paper can be used as consideration for make a decision regarding to integrity analysis of pressure vessel.
Structural Analysis of Pylon Head for Cable Stayed Bridge Using Non-Linear Finite Element Method Akbar, Musthafa; Nugraha, Aditya Sukma
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 51 No 1 (2018): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (770.994 KB) | DOI: 10.36842/jomase.v51i1.40

Abstract

Cable-stayed bridge is a type of bridge structure that commonly used for long-span range. This study provides an important opportunity to advance the understanding nonlinearities of material and geometry which is used for pylon of cable-stayed bridge structure. This study limited to response of pylon structure subjected to tension load which already calculated previously using structural analysis program. The methodology of structural analysis in order to determine working stress in the pylon structure under cable tension load is based on non-linear finite element method by incorporating an elastic-plastic material model and involve large deformation logarithm. In this study, laboratory experiment was held using test method ASTM A370. In finite element of plasticity analysis Ramberg-Osgood model was used to generate stress-strain curve of material. Based on finite element analysis that we have done, both of pylon structure will be fail or experience permanent plastic deformation if it subjected to loading conditions as mentioned in this research. The most critical regions in the structure are at Section A2 for left side pylon and at Section A11 for right side pylon. In critical regions, maximum Von-Misses stress reach 427.96 MPa for left side pylon and 430.56 MPa for right side pylon. Those stress value are beyond yield strength of material which is used for the structure. Design optimization can be done for the structure with some considerations, e.g. modification of design in the critical region, improve material properties or just change thickness of material in the critical regions.
The Performance of Undershot Water Turbine Combined With Spiral Tube Pump On Empowerment of Energy Resources Local Contiguous Small River Asral, Asral; Akbar, Musthafa; Syafri, Syafri
Journal of Ocean, Mechanical and Aerospace -science and engineering- Vol 42 No 1 (2017): Journal of Ocean, Mechanical and Aerospace -science and engineering- (JOMAse)
Publisher : International Society of Ocean, Mechanical and Aerospace -scientists and engineers- (ISOMAse)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1368.747 KB) | DOI: 10.36842/jomase.v42i1.186

Abstract

Hundreds of kilometers of irrigation canals are generally contiguous the village has not been maximally helpful as well most of damaged. Basically, in the water flow available an amount of energy could be harnessed as a renewable energy resources. Shortage of water and electricity supplies are the major issues encountered by the villager. Irrigation canals have head differences including low coupled lies in lowland areas. Picohydro electric generation, undershot-type water turbine suited for low high head applications in attemp to gain the electricity. To move the water, spiral tube pump mounted on the turbine can be installed simultaneously on generating systems. The turbine developed has an outer diameter of 2 m with 18 pieces of straight blade prepared from the material of aluminum. On the side of the turbine wall embeded the spiral tube pump with 5 coils was designed to operate concurrently with electrical generation. The height of water resources varied by controlling the opening of sluice gates to find out the potential. Throughout study the maximum electric voltage achievements was 125 volt. At the same time, the pump discharged the water with 9 liters per menit. These results provide sufficient supply of freshwater and electrical power for a family at contiguous area.
Pengembangan Media Promosi dan Media Informasi Wisata di Kelurahan Batu Bersurat, Kabupaten Kampar, Riau Anuar, Kaspul; Huda, Feblil; Fatra, Warman; Herisiswanto; Faisal, Gun; Rosa Putra Cupu, Dedi; Somadona, Sonia; Akbar, Musthafa; Martin, Awaludin; Nazaruddin; Syafri
Aksiologiya: Jurnal Pengabdian Kepada Masyarakat Vol 7 No 4 (2023): November
Publisher : Universitas Muhammadiyah Surabaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30651/aks.v7i4.10738

Abstract

Potensi objek wisata yang terdapat di Batu Bersurat belum tergarap dengan serius dan maksimal. Hal ini dapat dilihat dari minimnya sarana informasi dan promosi terkait keberadaan objek wisata di wilayah ini. Selain itu, minimnya keberadaan sarana pendukung turut menjadi penyebab rendahnya kunjungan wisatawan di wilayah ini. Berdasarkan pada permasalahan tersebut. Tim melaksanakan kegiatan pengabdian dalam bentuk pengembangan sarana dan penyediaan akses informasi wisata dalam rangka meningkatkan minat dan kunjungan wisatawan di Kelurahan Batu Bersurat, Kabupaten Kampar. Kegiatan pengabdian ini diawali dengan pembuatan foto udara dan foto landscape di area wisata Batu Bersurat dengan menggunakan wahana pesawat terbang tanpa awak tipe fixed wing. Selanjutnya kegiatan dilanjutkan dengan pembuatan video udara sinematik dengan memanfaatkan dua unit pesawat tanpa awak tipe rotary wing (drone). Hasil dari pembuatan media promosi wisata berbentuk video udara sinematik, foto landscape dan foto udara, selanjutnya diintegrasikan ke dalam media informasi wisata berbasis website yang juga dibuat oleh tim pengabdian. Diharapkan dengan adanya media promosi dan media informasi wisata ini, memudahkan pengelola objek wisata di Batu Bersurat, untuk mempromosikan ke khalayak ramai terkait keindahan objek wisata yang terdapat di Batu Bersurat.