Analisis Water Turbine Vortex Terhadap Daya dan putaran Optimum Yang Dihasilkan Pada Pembangkit Listrik Tenaga Piko Hidro

Turbin pusaran air (vortex) adalah salah satu jenis turbin yang memanfaatkan pusaran air di sekeliling sumbu vertikal sebagai media perantara energi sehingga terjadi perbedaan tekanan yang menyebabkan turbin berputar. Turbin vortex ini dapat dimanfaatkan sebagai pembangkit listrik tenaga piko hidro, tujuan penelitian yaitu untuk mengetahui putaran dan daya yang  paling optimum yang dihasilkan dari water turbin vortex dengan ketinggian sudu  20cm kemiringan 25°, ketinggian sudu 40cm kemiringan 25° dan bentuk kurvatur. Hasil analisis penelitian Perubahan water vortex Turbine dengan ketinggian sudu  20cm kemiringan 25° pada bukaan katup 900 debit 3,2 l/det menghasilkan kecepatan putar sudu 114,4 rpm dan daya yang dihasilkan sebesar 3,72 Watt dan pada variasi ketinggian sudu 40cm kemiringan 25° pada bukaan katup 900 debit 3,2 l/det menghasilkan kecepatan putar sudu 112 rpm dan daya yang dihasilkan sebesar 3,248 Watt, untuk bentuk kurvatur pada bukaan katup 900 debit 3,2 l/det menghasilkan kecepatan putar sudu 117,7 rpm dan daya yang dihasilkan sebesar 4,34 Watt. Hasil yang diperoleh daribentuk sudu wter turbin vortax yang menghasilkan putaran dan daya listrik paling optimal terdapat pada bentuk kurvatur, menghasilkan daya listrik terbesar pada bukaan katup 900 debit 3,2 l/det dengan kecepatan putar turbin mencapai 117,7 rpm dan daya yang dihasilkan sebesar 4,34 WattKata Kunci: water turbin vortex, daya listrik, putaran turbi

Evaluasi Ergonomi pada Kursi Roda untuk Anak Cerebral Palsy Menggunakan Digital Human Modeling

Cerebral palsy is caused by brain damage that manifests as motor dysfunction. The most prevalent form of cerebral palsy is spastic diplegia, which causes walking difficulties. People with cerebral palsy, particularly children, require mobility aids, such as wheelchairs, to perform daily tasks. When designing wheelchairs for children with cerebral palsy, ergonomic evaluation is required to ensure that the resulting wheelchair is safe and will not pose a risk in the future. This paper investigates the use of digital human modeling to evaluate the ergonomics of wheelchairs for children with cerebral palsy. The method is used to collect samples from 5 to 18-year-old children with cerebral palsy. Digital human modeling is used to simulate and evaluate ergonomics using anthropometric data. The results obtained for the wheelchair dimensions are suitable for the 95th percentile value, while the seat length exceeds the popliteal length for the 50th percentile value. The ergonomic evaluation yielded satisfactory results for the lower back analysis parameter, and the comfort evaluation yielded satisfactory results for the 95th percentile value. In contrast, the 5th percentile value indicates knee discomfort in both the right and left knee

Development of Data Acquisition System on an Arduino-Based Tensile Test Machine for Composite Materials

A tensile testing machine with a lower load capacity is needed to identify the mechanical properties of composite materials. Tensile testing machines for composite materials are available in the market but at high prices. Previously, using a pneumatic system, a tensile testing machine for composite materials with a maximum load of 2000N was developed. However, this tensile test machine still needs improvement because the display of eventuating forces is only in numbers, not yet including a test graph. Therefore, this study developed a prototype data acquisition system for a tensile test machine to record the test results in more detail, both numbers and graphs. This data acquisition system uses the Arduino Uno Microcontroller, which processes data from the load cell through the HX711 module intermediary. A tensile test was carried out using a bamboo fiber composite material to validate the results of testing the prototype of this data acquisition system. Furthermore, the test results data are compared with the results on the indicators of the existing tensile test machine. The test was carried out nine times with an average tensile force of 1.66 N/mm2, while the average tensile force on the tool indicator was 2.02 N/mm2. There is a difference in the average test results equal to 12%. This difference is a systematic error because nine experiments have shown the same trend, with standard error and standard deviation of 0.3368 and 0.1123, respectively. The systematic error is compensated through calibration between the load cell of the tensile test machine and a series of data acquisition systems based on Arduino Uno. &nbsp

Simulation-based Prediction of Structural Design Failure in Fishing Deck Machinery a Hydraulic Type with Finite Element Method

The fishing deck machinery is the tools used to collect fish in fishing activities. Fishing deck machinery is intended to improve the effectiveness of fishing operations. The mission of the Ministry of Marine Affairs and Fishery Year 2015-2019 in the Regulation of the Minister of Marine and Fisheries No. 45/PERMEN-KP/2015 which is a priority is to provide assistance for fishing facilities for fishermen; it is necessary to develop and optimize fishing deck machinery. To assure the safety and dependability of these fishing deck machinery, calculations, simulation and functional tests are needed. This paper discusses the prediction of structural failure in the design of fishing deck machinery a hydraulic type with finite element method simulation approach. The results of the FEM simulation analysis are (i) the maximum value of von-Mises stress is greater than the ultimate tensile strength of the material; (ii) 1st principal stress value minimum is smaller than the ultimate tensile strength of material; (iii). the Poisson ratio value higher than the Poisson ratio value of the material. Base on the simulation result, the structural design of fishing deck machinery is safety