Articles
<![CDATA[An Experimental Investigation of Passive Variable-Pitch Vertical-Axis Ocean Current Turbine ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[I.K.A.P Utama]]>;
<![CDATA[Erwandi Erwandi]]>;
<![CDATA[Aries Sulisetyono]]>
<![CDATA[ Journal of Engineering and Technological Sciences Vol. 43 No. 1 (2011) ]]>
Publisher : <![CDATA[Institute for Research and Community Services, Institut Teknologi Bandung ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.5614/itbj.eng.sci.2011.43.1.3
<![CDATA[Vertical-axis hydrokinetic turbines with fixed pitch blades typically suffer from poor starting torque, low efficiency and shaking due to large fluctuations in both radial and tangential force with azimuth angle. Maximizing the turbine power output can be achieved only if the mechanism of generation of the hydrodynamic force on the blades is clearly identified and tools to design high-performance rotors are developed.This paper describes an initial experimental investigation to understand more of the performance on vertical-axis turbine related to the effect of fixed-pitch and passive variable-pitch application using airfoil NACA 0018. Comparative analysis according to aspects of rotation and tip speed ratios was discussed. Information regarding the changes of foil position in passive variable-pitch during rotation at a limited range of flow velocity variations test was obtained and analyzed. ]]>
<![CDATA[Thermal Energy Storage Optimization in Shopping Center Buildings ]]>
<![CDATA[Totok R. Biyanto]]>;
<![CDATA[Akhmad F. Alhikami]]>;
<![CDATA[Gunawan Nugroho]]>;
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Ridho Bayuaji]]>;
<![CDATA[Hudiyo Firmanto]]>;
<![CDATA[Joko Waluyo]]>;
<![CDATA[Agus Imam Sonhaji]]>
<![CDATA[ Journal of Engineering and Technological Sciences Vol. 47 No. 5 (2015) ]]>
Publisher : <![CDATA[Institute for Research and Community Services, Institut Teknologi Bandung ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.5614/j.eng.technol.sci.2015.47.5.7
<![CDATA[In this research, cooling system optimization using thermal energy storage (TES) in shopping center buildings was investigated. Cooling systems in commercial buildings account for up to 50% of their total energy consumption. This incurs high electricity costs related to the tariffs determined by the Indonesian government with the price during peak hours up to twice higher than during off-peak hours. Considering the problem, shifting the use of electrical load away from peak hours is desirable. This may be achieved by using a cooling system with TES. In a TES system, a chiller produces cold water to provide the required cooling load and saves it to a storage tank. Heat loss in the storage tank has to be considered because greater heat loss requires additional chiller capacity and investment costs. Optimization of the cooling system was done by minimizing the combination of chiller capacity, cooling load and heat loss using simplex linear programming. The results showed that up to 20% electricity cost savings can be achieved for a standalone shopping center building.]]>
<![CDATA[Novel Design of a Vertical Axis Hydrokinetic Turbine âStraight-Blade Cascaded (VAHTâSBC): Experimental and Numerical Simulation ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Erna Septyaningrum]]>
<![CDATA[ Journal of Engineering and Technological Sciences Vol. 50 No. 1 (2018) ]]>
Publisher : <![CDATA[Institute for Research and Community Services, Institut Teknologi Bandung ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.5614/j.eng.technol.sci.2018.50.1.5
<![CDATA[A promising technology to reduce dependency on fossil fuels is hydrokinetic energy conversion using either turbine and non-turbine technology. Hydrokinetic turbine technology is penalized by low efficiency and lack of self-starting. This study involved experimental testing and numerical simulation of a novel hydrokinetic turbine design, called a Vertical Axis Hydrokinetic Turbine â Straight-Blade Cascaded (VAHTâSBC). Three configurations of the design were tested. Model 1 had 3 passive-pitch blades, while Model 2 and Model 3 had 6 and 9 blades respectively, where the outer blades were passive-pitch and the others fixed-blade. Both in the experimental test and in the numerical simulation Model 3 outperformed the other two models. The Cp of Model 3 was 0.42, which is very close to the theoretical Cp for VAHTs (0.45). It worked properly at low TSR. A CFD simulation based on the RANS solver was performed to gain supplementary information for performance investigation. This simulation confirmed that the torque changes because of the change in angle of attack as the turbine rotates. Because they have different numbers of blades, each model has different periodical torque fluctuation patterns. This study verified that utilization of cascaded blades and a passive-pitch mechanism is able to improve turbine performance.]]>
<![CDATA[Site Test Performance and Numerical Study of Vertical Axis Hydrokinetic Turbine Straight Blade Cascaded (VAHT–SBC) ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Sarwono Sarwono]]>;
<![CDATA[Fernando Parsaulian Panjaitan]]>;
<![CDATA[Erna Septyaningrum]]>;
<![CDATA[Nuril Hidayati]]>
<![CDATA[ Journal of Engineering and Technological Sciences Vol. 53 No. 1 (2021) ]]>
Publisher : <![CDATA[Institute for Research and Community Services, Institut Teknologi Bandung ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.5614/j.eng.technol.sci.2021.53.1.2
<![CDATA[The Vertical Axis Hydrokinetic Turbine â Straight Blade Cascaded (VAHT-SBC) is a type of energy generation technology developed to meet the increasing demand for renewable energy. Previous studies have been carried out to enhance the efficiency of the turbine through several aspects. To deploy a turbine on site, a study on its power generation and conversion is needed. In this research, the VAHTâSBC was integrated with a permanent magnet synchronous generator (PMSG) by a pulley and belt transmission system. This study was conducted by experimental and numerical analysis. The CFD simulation result showed that the highest torque of the turbine was found at 0° and 360°, with an average value of 23.923 Nm and with current velocity at 0.92 m/s. The experimental data showed that the voltage and frequency were proportional to the generator rotational speed and inversely correlated with the load given to the integration system. In the inverter, the voltage and frequency values were stable at 230 V and 56 Hz respectively. The VAHT-SBC prototype was able to produce a maximum power of 50 W on site, with a current velocity of 0.82 and 0.92 m/s.]]>
<![CDATA[Ketidakstabilan Gaya dan Interaksi Fluida-Struktur pada Turbin Sumbu Vertikal untuk Pembangkit Energi Arus Laut ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[I.K.A.P. Utama]]>;
<![CDATA[Erwandi Erwandi]]>;
<![CDATA[Aries Sulisetyono]]>
<![CDATA[ Jurnal Teknik Mesin (Sinta 3) Vol. 11 No. 1 (2009): APRIL 2009 ]]>
Publisher : <![CDATA[Institute of Research and Community Outreach, Petra Christian University ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
<![CDATA[Structure in a fluid flow general will lead to fluctuations. This fluctuation is called the flow-induced oscillation and became an important aspect within the scope of the flow that results in natural excitation modes. The existence of feedback loops in the fluid-structure interaction is highly non-linear and in certain circumstances, this will dominate the movement in the system fluid-structure interaction. This also occurs in the generation of energy from ocean currents renewable energy resource. As the hydrodynamics forces are fluctuate, it can cause structural damage due to vibration caused by the turbine which is working continuously in the ocean environment. This paper provides analysis of the instability of the force acting on the turbine works in a fluid flows. Aspects of interaction between fluid and structure are discussed in a rotating turbine condition management and its dynamics pattern. Numerical simulations research is carried out with rpm data obtained from the previous prototype testing. Simulations performed using NACA 0018 foil type without twist and there are two phenomenon patterns generated from the resultant force. Simulation results indicating the harmonic force fluctuations during a full 360 degrees turbine rotation. Comparison of drag coefficient and lift coefficient at angle of attack of 0-90 degrees and resulting the maximum error of 6% lift coefficient and 7% for drag coefficient. Dynamics force fluctuation are simulated in the interval of 5 degrees with variation of the upstream velocity of 1 m/s, 2 m/s, and 3 m/s. Abstract in Bahasa Indonesia: Struktur dalam sebuah aliran fluida pada umumnya akan menimbulkan fluktuasi pada komponen-komponennya. Fluktuasi ini disebut sebagai osilasi yang disebabkan oleh fluida (flow-induced oscilation) dan menjadi aspek penting dalam lingkup aliran yang menyebabkan terjadinya mode-mode eksitasi alami (naturalexcitation modes). Adanya feedback loop dalam interaksi fluida-struktur yang sangat tidak linier dan dalam keadaan yang tertentu, maka hal ini dapat mendominasi gerakan dalam sistem interaksi fluida-struktur. Hal ini juga terjadi pada pembangkitan energi dari sumber energi terbarukan arus laut. Dengan adanya beban hidrodinamik laut yang berfluktuasi, sehingga dapat menyebabkan kerusakan struktur karena getaran yang diakibatkan oleh turbin yang bekerja terus-menerus di dalam fluida laut. Makalah ini menganalisis ketidakstabilan gaya yang bekerja pada turbin yang bekerja di dalam sebuah fluida laut yang bergerak dinamis. Aspek interaksi antara fluida dan struktur dibahas dalam kondisi turbin yang berotasi penuh beserta dinamika perubahan gayanya. Penelitian dilakukan secara simulasi numerik dengan data rpm yang telah didapatkan dari pengujian model sebelumnya. Simulasi dilakukan dengan menggunakan foil jenis NACA 0018 tanpa puntiran (twist). Hasil simulasi mengindikasikan adanya fluktuasi gaya yang harmonik selama turbin berotasi penuh 360 derajat terdapat fenomena munculnya dua pola fluktuasi dari resultan gaya yang dihasilkan. Perbandingan nilai Koefisien gaya seret (Cd) dan Koefisien gaya angkat (Angkat) dilakukan pada sudut serang 0-90 derajat dan memberikan nilai kesalahan maksimum 6% untuk Cl dan 7% untuk Cd. Dinamika perubahan gaya disimulasikan dalam interval 5 derajat dan menggunakan variasi kecepatan upstream dengan nilai 1 m/s, 2 m/s, dan 3 m/s. Kata kunci: Arus laut, fluktuasi gaya, getaran, interaksi fluida-struktur]]>
<![CDATA[Performance of Seawater Activated Battery as Alternative Energy Resources ]]>
<![CDATA[Masrufaiyah Masrufaiyah]]>;
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Gunawan Nugroho]]>;
<![CDATA[Totok R Biyanto]]>;
<![CDATA[Nur Laila Hamidah]]>
<![CDATA[ IPTEK The Journal of Engineering Vol 3, No 1 (2017) ]]>
Publisher : <![CDATA[Lembaga Penelitian dan Pengabdian kepada Masyarakat ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
DOI: 10.12962/j23378557.v3i1.a2266
<![CDATA[Research on Freshwater and Seawater batteries, which using Al and Cu electrodes at variation of different electrolyte salinity, distance between electrodes and flowrate of electrolyte has been carried out. The galvanostatic discharge and Electrochemical Impedance Spectroscopy (EIS) of Al and Cu in seawater were investigated. The results showed the optimum condition with significant average potential discharge of 45,02 mV and current of 0,440 mA obtained from combination of 5% electrolyte salinity, 2 cm space between electrodes and 0,5 liter/hour electrolyte rate. EIS studies revealed that the Al and Cu interficial electrochemical process in seawater was determined by an activation controlled reaction]]>
<![CDATA[Simulation Bursting Effects To The Performance Vertical Axiz River Turbine Using Computational Fluid Dynamics ]]>
<![CDATA[Aank Suseno]]>;
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Gunawan Nugroho]]>
<![CDATA[ IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015 ]]>
Publisher : <![CDATA[Institut Teknologi Sepuluh Nopember ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
Full PDF (171.182 KB)
|
DOI: 10.12962/j23546026.y2015i1.1021
<![CDATA[Turbulent flow in the open channel, often exhibit a phenomenon bursting in expansion or inhibition case. This phenomenon disturbing to the flow at the turbine area. In this study, Research to analyze the occurrence of interference bursting in the river turbine area, done by simulating the river flow with a variety of depths ratio y/L, using vertical turbine NACA 0018 in a trapezoidal channel, with k-ԑ turbulence models in CFD. From the simulation results the smaller ratio of the depth y/L, the force of turbulence flow (bursting flow) at the turbine increases.]]>
<![CDATA[An ANP (Analytic Network Process)-based Multi-Criteria Decision Approach for The Selection of Sugar-Cane Industry Development ]]>
<![CDATA[Ferizandi Qauzar Gani]]>;
<![CDATA[Ridho Hantoro]]>
<![CDATA[ IPTEK Journal of Proceedings Series No 1 (2018): 3rd International Seminar on Science and Technology (ISST) 2017 ]]>
Publisher : <![CDATA[Institut Teknologi Sepuluh Nopember ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
Full PDF (189.11 KB)
|
DOI: 10.12962/j23546026.y2018i1.3507
<![CDATA[Acknowledging the issue of energy sustainability, the sugar industry has begun to look at plans to sell electricity to address energy sustainability issues. A scenario with the potential to sell excess electricity motivates this research to analyze the strategies of the sugar industry development. In such situations an ANP approach is applied for the selection of appropriate strategies. This study analyzes the potential for electricity sales in two alternative plant development strategies of three sugarcane industries which from the results, Strategy A (cogeneration scheme) allows to sell electricity for 223-293 days while strategy B (independent power plant scheme) allows to sell throughout the year. The result also shows that by using ANP, it is found that strategy A is better than strategy B]]>
<![CDATA[Emission Reduction Study for Eco-Campus Program, Case Study in Sepuluh Nopember Institute of Technology Indonesia ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Detak Yan Pratama]]>;
<![CDATA[Endah Laksmi Nugraha]]>;
<![CDATA[Rizky Nanda Puspitasari]]>
<![CDATA[ IPTEK Journal of Proceedings Series No 6 (2017): The 3rd International Conference on Civil Engineering Research (ICCER) 2017 ]]>
Publisher : <![CDATA[Institut Teknologi Sepuluh Nopember ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
Full PDF (532.547 KB)
|
DOI: 10.12962/j23546026.y2017i6.3277
<![CDATA[Emission of CO2 in Indonesia is high relatively and have reached 1,55-ton carbon (5,67 ton CO2 – eq) per capita. It is predicted to increase up to 3,22-ton carbon per capita in 2050 as increasing of population growth. Indonesian Government has issued the policy for decreasing greenhouse gasses effect below 26% in 2020. It proposed to all of society not only public and private institutions, but also education institution like campus. This study is aimed to identify the factors which can influence greenhouse gasses effect, including carbon emission in transportation, waste management and electrical consumption in Sepuluh Nopember Institute of Technology (ITS). It is projected to support implementation of ITS eco campus program more effectively. Therefore, this study has formulated local planning and policy which can be implemented by campus community to decrease carbon emission and organize ITS as real eco-campus.]]>
<![CDATA[Simulation of Solar-Assisted Single Stage Absorbtion Chiller as Ice Maker Based on MATLAB ]]>
<![CDATA[Ridho Hantoro]]>;
<![CDATA[Dwi Ganef Janesa]]>
<![CDATA[ IPTEK Journal of Proceedings Series No 1 (2015): 1st International Seminar on Science and Technology (ISST) 2015 ]]>
Publisher : <![CDATA[Institut Teknologi Sepuluh Nopember ]]>
Show Abstract
|
Download Original
|
Original Source
|
Check in Google Scholar
|
Full PDF (132.43 KB)
|
DOI: 10.12962/j23546026.y2015i1.1123
<![CDATA[In this research, the system is described in the two-dimensional form to simplify the completion and modeling. There are various kinds of components, among others: evaporator, condenser, Solution Heat Exchanger (SHX), absorber, generator (including solar collector), pumps, and expansion valve.]]>
