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KARAKTERISTIK PERPINDAHAN PANAS PADA PENDINGINAN MODEL SUNGKUP REAKTOR AP1000 DENGAN UDARA YANG BERSIRKULASI ALAMIAH Hermawan, Nanang Triagung Edi; Pasek, Ari Darmawan; Umar, Efrizon
Teknologi Indonesia Vol 34 (2011)
Publisher : LIPI Press

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/jti.v34iKhusus.40

Abstract

Electric energy demand always grows up. Nuclear energy is one of energies alternative in the future. AP1000 is III+ generation reactor that will possibly built in Indonesia. One of the safety AP1000s features is containment cooling system by natural circulation of air. Experimental study on heat transfer characteristic in containment surface of AP1000 model was done in laboratory scale. From these research, it knows that critical heat fl ux happened at power 2010 watt or 553,47 watt per meter square heat fl ux. Empirical correlation from these research is Nux = 7,086. Rax*0,1906; 2,09 x 106 < Rax* < 1,24 x 1012 for cylindrical concentric part and Nux = 1,308. Rax*0,2527; 7,51 x 105 < Rax* < 7,08 x 1010 for ellipse sector.
Efficiency Analysis for Plate Type Heat Exchangers Using Nanofluids in the Primary Cooling System of the TRIGA 2000 Nuclear Reactor with Computational Fluid Dynamics Code Yusuf, Yusuf; Ramadhan, Anwar Ilmar; Umar, Efrizon; Fitriana, Rian; Firmansyah, Firmansyah; Azmi, Wan Hamzah
Journal of Applied Sciences and Advanced Technology Vol. 6 No. 3 (2024): Journal of Applied Sciences and Advanced Technology
Publisher : Faculty of Engineering Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24853/jasat.6.3.117-128

Abstract

The TRIGA reactor is equipped with a primary cooling system that transfers heat from the reactor tank water to the secondary cooling system. Heat transfer in this system occurs mainly in plate-type heat exchangers located in the reactor building, using forced convection with the help of primary and secondary pumps. This research aims to evaluate the effectiveness, efficiency, heat transfer rate, and temperature difference. The analysis was carried out through CFD (Computational Fluid Dynamics) modeling using ANSYS Spaceclaim for geometric design and ANSYS FLUENT for simulation. Simulations using ZrO2-Water Nanofluid with volume concentrations of 0.2%, 0.6%, and 1% and variations in mass flow rates of 15 kg/s, 20 kg/s, and 25 kg/s. The simulation results show the distribution of temperature, pressure and fluid velocity. The theoretical analysis of the plate type heat exchanger shows that the use of ZrO2 with a concentration of 1% has the highest efficiency, which is 3.39% at a mass flow rate of 25 kg/s, and an efficiency of 64.82% at a mass flow rate. as much as 15 kg/s.
Investigation of Thermal Conductivity and Dynamics Viscosity of Green Nanofluids (ZrO2-SiO2) Ramadhan, Anwar Ilmar; Saptaji, Kushendarsyah; Hendrawati, Tri Yuni; Sari, Alvika Meta; Umar, Efrizon; Aziz, Azmairit; Semendo, Rifqi Putra; Setiawan, Hanif Rama Yuda; Firmansyah, Firmansyah
Jurnal Teknologi Vol 16, No 2 (2024): Jurnal Teknologi
Publisher : Fakultas Teknik Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24853/jurtek.16.2.301-312

Abstract

In recent years, research has been directed towards improving the thermophysical properties of single-component nanofluids. Therefore, hybrid or composite nanofluids are developed to improve heat transfer performance. The thermophysical properties of ZrO2-SiO2 nanoparticles suspended in a mixture of water (W) and ethylene glycol (EG) with vol 60:40 or Green Nanofluids for various volume concentrations were investigated. Experiments were performed for volume concentrations of 0.1, 0.2, and 0.3% of green nanofluids at 50, 60, 70, and 80°C. Measurements of thermal conductivity and dynamic viscosity are performed at temperatures ranging from 50-80°C. The highest thermal conductivity of the green nanofluids is obtained at a concentration of 0.3%, and the maximum increase is up to 37.5% higher than the base fluid (EG/W). Meanwhile, evidence from the dynamic viscosity of green nanofluids is affected by concentration and temperature. Furthermore, the green nanofluids behave as a Newtonian fluid in a volume concentration of 0.1-0.3%. In conclusion, the combination of increased thermal conductivity and dynamic viscosity at a concentration of 0.3% has optimal conditions, which has more advantages for heat transfer than at other concentrations.
Effect of Mass Composition on Nano Zircon Synthesize from Local Zircon Sand Using Soda-Precipitation-Calcination-Caustic Fusion Method Sari, Alvika Meta; Ramadhan, Anwar Ilmar; Rahardja, Istianto Budhi; Umar, Efrizon; Yudistirani, Sri Anastasia; Faisal, Akmal Imam; Fikriyansyah, Fikriyansyah; Azmi, Wan Hamzah
Jurnal Teknologi Vol 16, No 2 (2024): Jurnal Teknologi
Publisher : Fakultas Teknik Universitas Muhammadiyah Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24853/jurtek.16.2.169-178

Abstract

Zircon sand has the major component of ZrO2 with impurities SiO2, Fe2O2, and TiO2. Zircon sand can be synthesized using various methods, such as caustic fusion method. This research purposed to determine the effect of the mass composition of NaOH on fusion process of zircon sand and to find the optimal mass ration of NaOH on yield and characteristics of nano zircon produced. This research was conducted using caustic fusion and precipitation process to obtain the mass ration of NaOH in best zircon sand fusion (melting) process. The nano zircon obtained was analyzed its size using SEM and chemical composition using FTIR. The result show that the correlation between NaOH ration and yield following the equation y = 0.42x2-2.532x+3.908 and R2 =0.9696. It showed that the higher NaOH composition will reduce the size of nano zircon. The optimum NaOH ratio is 1 : 3.6 with size od 41.983 nm and yield 1.84% which in white, odorless and powder texture. The FTIR spectrum showed the presence of the -Zr-O2 functional groups at wave numbers 600 – 700 cm-1.
Experimental investigation on stability and thermal conductivity of SiO2 nanoparticles as green nanofluids for application thermal system Ramadhan, Anwar Ilmar; Umar, Efrizon; Hendrawati, Tri Yuni; Sari, Alvika Meta; Rahardja, Istianto Budhi; Aziz, Azmairit; Firmansyah, Firmansyah; Yulianto, Sulis; Azmi, Wan Hamzah
SINERGI Vol 28, No 3 (2024)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2024.3.018

Abstract

In the last few years, much research has focused on the stability and improvement of the thermo-physical properties of single-component nanofluids. Some studies have not made many improvements to the stability and thermophysical properties of various types of green nanofluids from several variations of nanoparticles. Green nanofluids must be developed to improve heat transfer performance from their stability and thermal conductivity factors. Stability and thermal conductivity of Nano-silicate suspended in a base mixture of water /ethylene glycol with the ratio of 60:40, different volume concentrations were investigated. The experiments carried out were the stability of the green nanofluids investigated for volume concentrations of 0.1~0.3% and temperature conditions from 30 to 70°C for thermal conductivity measurement using TEMPOS Thermal Properties Analyzer. The experimental results showed that the stability analysis of the green nanofluids prepared by the UV-Vis method was stable up to 30 days after preparation with a sonication time of 1 hour with a ratio of 70-80%. The evaluation of the zeta potential for green nanofluids obtained a value of 33.57 mV with a moderate stability classification. The highest thermal conductivity for the green nanofluids was obtained at 0.3%, and the maximum increase was 17% higher than that of the base liquid (W/EG). Green nanofluids with a concentration of 0.1% gave the lowest effective thermal conductivity of 1.09 time at 70°C.
Heat transfer performance of Al2O3-TiO2-SiO2 ternary nanofluids in plain tube with wire coil inserts Ramadhan, Anwar Ilmar; Umar, Efrizon; Azmi, Wan Hamzah; Sari, Alvika Meta
Mechanical Engineering for Society and Industry Vol 4 No 1 (2024)
Publisher : Universitas Muhammadiyah Magelang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31603/mesi.10996

Abstract

The ternary nanofluids are considered due to their advantages in overcoming the stability drawback of mono and binary nanofluids. This study aims to heat transfer performance of Al2O3-TiO2-SiO2 ternary nanofluids in plain tube with wire coil under experimental. The ternary nanofluids were formulated using the composition ratio of 20:16:64 by volume in various volume concentrations ranging from 0.5 to 3.0%. Thermal conductivity and dynamic viscosity of ternary nanofluids were measured with KD2 Pro Thermal Properties Analyzer and Brookfield LVDV III Rheometer. Experimental forced convection heat transfer was carried out using a fabricated setup for Reynolds numbers from 2,300 to 12,000 at bulk temperature of 70 °C in plain tubes with wire coil inserts (0.83 ≤ P/D ≤ 2.50). Experimental results are highest thermal conductivity enhancement of 24.8% was obtained for ternary nanofluids at 3.0% volume concentration. The 3.0% volume concentration also shows the highest viscosity at all temperatures. The maximum heat transfer improvement for ternary nanofluids in a plain tube with wire coil (P/D-0.83), was attained by 3.0% volume concentration of up to 199.23%. The average TPF of the wire coil increases compared to the plain tube and improves further with volume concentrations in the range of 2.39 to 2.84.
Heat Transfer Analysis and Friction Factor of Ternary Nanofluids with Twisted Tape Inserts Ramadhan, Anwar Ilmar; Azmi, Wan Hamzah; Lasman, As Natio; Umar, Efrizon; Sharma, Korada Viswanatha
Indonesian Journal of Computing, Engineering, and Design (IJoCED) Vol. 6 No. 2 (2024): IJoCED
Publisher : Faculty of Engineering and Technology, Sampoerna University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35806/ijoced.v6i2.473

Abstract

This study investigates the heat transfer efficiency and friction factor of ternary nanofluids (Al₂O₃-TiO₂-SiO₂) in a simple tube equipped with a twisted tape. Ternary nanofluids, prepared using a volume-based composition ratio of 20:16:64, were tested at various volume concentrations ranging from 0.5% to 3.0%. Forced convection heat transfer experiments were conducted under varying Reynolds numbers (2,300 to 12,000) and a bulk temperature of 70 °C. The results indicate that the maximum viscosity occurs at a volume concentration of 3.0%. The highest increase in heat transfer for ternary nanofluids in a simple tube with twisted tape (H/D = 2.0) was achieved at a volume concentration of 3.0%, reaching 225.35%. Compared to a plain tube, the average thermal performance factor (TPF) of the twisted tape was significantly improved, with a further increase observed when the volume concentration rose from 2.73% to 3.22%.