sugeng hadi susilo
@polinema.ac.id
Mechanical Engineering
Politeknik Negeri Malang
RESEARCH INTERESTS
Mechanical Engineering, Material, Renewable Energy
Scopus Publications
Scopus Publications
Sugeng Hadi Susilo, Azam Muzakhim Imanudin, Taufiq Rochman, and Supriatna Adhisuwignjo
OU Scientific Route
This paper discusses the impregnation of Cu atoms at carbonization temperature of water hyacinth bio carbon composite. This composite is used as an absorber of electromagnetic waves. Because the inference of electromagnetic waves can cause damage to other electronic equipment. In addition, electromagnetic wave radiation can cause various human health problems. The purpose of the research is to obtain a material that is able to absorb electromagnetic waves and increase electrical conductivity, impregnation of Cu atoms at carbonization temperature of water hyacinth bio carbon composite. The composite material uses a composition ratio of water hyacinth powder and phenol-formaldehyde of 30:70. The carburization temperatures used were 600 °C, 800 °C, and 1000 °C with a heat increase rate of 7 °C/minute. This study used Scanning Electron Micrograph (SEM), X-Ray Diffraction (XRD), LCR Meter, and vector network analyzer. The results show that the impregnation of Cu atoms at carbonization temperature can increase the area of the nanostructure, thereby increasing the formation of micropores in the composite. The higher the carbonization temperature, the percentage of Cu and carbon compounds can increase, while the percentage of crystal structure decreases. Impregnation of Cu atoms further strengthens the composite's absorption of electromagnetic wave radiation. Impregnation of Cu atoms in water hyacinth bio carbon composites at carbonization temperature can increase the electrical conductivity of the composite. The results of this research have potential applications in the electronics industry, batteries, and electrical devices, and can be used to protect devices from electromagnetic interference, especially in telecommunications and the medical field
Zahratul Jannah, Sugeng Hadi Susilo, EIka Faizal, and Ratna Monasari
AIP Publishing
Asrori Asrori, Sulistyono Sulistyono, Sugeng Hadi Susilo, and Eko Yudiyanto
AIP Publishing
Azam Muzakhim Imammuddin, Septriandi Wirayoga, and Sugeng Hadi Susilo
IEEE
After the roasting process, coffee is divided into three categories: light, medium, and dark. To determine the level of classification of coffee beans that have been roasted manually, it takes people who are experts in the field of roasting. Each of the three types of roast classifications has a different level of water in the beans. Therefore, this tool was made to identify the roasting level of coffee beans by using the frequency value obtained from changes in the value of the capacitor, which is influenced by the dielectric material that exists between two pairs of copper plates. In addition, knowing the capacitance value and color sensor value for each roast classification is expected to be an additional variable for determining and classifying coffee beans. In previous studies, a coffee bean classification system was developed using different crosssectional areas of capacitors. In addition, an oscillator circuit with three note gates will also be used, and it is hoped that the resulting values will be more stable than previous studies. Internet of Things (IoT) technology and a grinding system are added to improve this system and carry out further research on the previous method. This is the basis of Industrial Revolution 4.0. The system has been tested 10 times and has a 100% success rate in the process.
Sugeng Susilo, G Gumono, and Agus Setiawan
Centre for Evaluation in Education and Science (CEON/CEES)
In recent years, the global energy demand, particularly the usage of fossil fuels as motor vehicle propellants such as gasoline and diesel, had steadily increased. This surge in consumption, alongside the burgeoning vehicle count, resulted in a depletion of petroleum reserves. Consequently, exploring alternative fuel sources became imperative. Hydrogen gas, derived from water through water electrolysis using an HHO generator, emerged as a promising alternative. This research investigated the impact of diverse copper and stainless-steel electrodes in varied electrolyte solutions and electrical currents for generating HHO gas. Employing an experimental methodology, the study modified an existing HHO generator, reassembling it with different materials based on the experimental design. Subsequent testing and data collection revealed that the highest flow rate of HHO gas, at 0.000807564 m3 /s, occurred using stainless-steel electrodes with an electrical current of 50 A and a 50% NaOH concentration. The study concluded that the size of the electric current and the amount of NaOH significantly influenced the speed of HHO gas flow, indicating a direct relationship between these factors and gas production.
Gunarianto, Endah Puspitosarie, and Sugeng Hadi Susilo
LLC CPC Business Perspectives
Company value plays a significant role in investment decisions, company performance assessment, and risk analysis. In addition, there is uncertainty or inconsistency in the relationship between factors such as sales, assets, and leverage that can affect company value. The study aims to analyze the effect of sales growth, asset growth, and leverage on company value in companies listed on the Indonesia Stock Exchange, especially in the LQ-45 index during the 2021–2022 period. The research method uses a quantitative approach with statistical tools and hypothesis testing. Regression analysis through path analysis models is used to test the proposed hypothesis. The results showed asset growth of 15.42%, debt-equity ratio of 1.7797, and high Price to Book Value (36.2721). Nonetheless, leverage does not act as a mediator in the relationship between asset growth and company value, defying the Modigliani-Miller theory. The finding highlights the complexity of such factors in the context of LQ-45 companies, emphasizing the need for prudent asset management and debt policy to enhance competitiveness. The findings have important implications for financial management and business strategy in a dynamic and competitive environment.
AgusTugas Sudjianto
International Journal of Geomate
Taufiq Rochman, Sumardi, Sugeng Hadi Susilo, and Handra Adhi Wardhana
Elsevier BV
Bagus Wahyudi, Akhmad Faizin, Andri Setiawan, Sugeng Hadi Susilo, and Hangga Wicaksono
OU Scientific Route
The potential of wind as an energy resource is still not widely used by the community through simple technology to produce electrical power. One simple technology is to use PVC pipe as the basic material for making wind turbine propellers. The purpose of this study was to determine the effect of variations in angle of attack and wind speed on the performance of a PVC pipe propeller wind turbine with an Elbow Tip. Material of blade propeller made by PVC pipe are slice half and twist from hub until tip with 90 degree of rotation. Dimension of width blade wider on the hub (3/4 of circular) and smaller on the tip (1/7 of circular). Face of blade on the hub side facing wind direction (axial) and face of blade on the tip side facing tangential direction or opposite with rotation. On the tip side installed the slice elbow with fit tip blade width. The propeller using PVC pipe with elbow tip is the important part of new design which has been test with CFD simulation and wind tunnel research with best result performance. This research uses CFD simulation and experimental methods with a comprehensive study of the aerodynamic behaviour characteristics in and around the turbine rotor. The results of the CFD simulation was found that the phenomenon positioning of momentum force were place on the outer radius due to addition elbow tip cause increasing the torque. By using elbow tip on blade propeller PVC Pipe Horizontal Axis Wind Turbine with 15° and 30° angle of attack could increasing torque about 200 % than without the elbow tip. Beside, using 45° angle of attack although additional with elbow tip could not increasing the torque when the wind speed on 7 m/s. The result of this research is important to know by public who interest build small grid wind turbine with low cost and easy manufacturing.
Asrori Asrori and Sugeng Hadi Susilo
OU Scientific Route
This paper discusses the application of Fresnel Lens Concentrator for Solar Water Heater which is a case study in Indonesia. The purpose of this study was to find an empirical equation of the relationship between Direct Normal Irradiance (Ib) and focal point temperature (Tf). The research location is Latitude: 7.9553 °S and Longitude: 112.6145°E. The SM-206 solar power meteris used.The Fresnel lenses are made of PMMA material. Its specifications are: diameter=1000 mm; weight=2 kg; thickness=2 mm; groove pitch=0.5 mm and focal length=880 mm.The main experimental setup consists of a PMMA Fresnel lens and a receiver. The conical cavity receiver has specifications; geometric concentration ratio,CRg=8, and V=2 Liters. Temperature measurement is done using a temperature data acquisition system. The K-type thermocouple is used to measure:
 1) ambienttemperature (Ta);
 2) the focal point temperature (Tf);
 3) receiverwall temperature (Tr);
 4) watertemperature (Tw).
 The experiment obtained the results of the empirical equation for the relationship between Direct Normal Irradiance (Ib) and focal point temperature (Tf). The increase in solar radiation produces a focus temperature, exponentially. At DNI 858 W/m2 it can produce a focal temperature of up to 1064 °C. The efficiency of the receiving cavity of the thermal cone which contains 2 litres of water and CRg=8 under conditions of relatively Direct Normal Irradiance ( =675 W/m²) is about 10.61 %. Furthermore, the energy that can be generated in heating water is 0.17–0.32 MJ, in 100 minutes. Heat convection and radiation loss can be reduced by adding an insulating layer to the walls and coating the surface with black
Sudarmadji Sudarmadji, Bambang Irawan, and Sugeng Hadi Susilo
Private Company Technology Center
This study aims to improve the performance of the vehicle's cooling system called the radiator, which is part of increasing energy efficiency. Research has been done to investigate the convective heat transfer of hybrid nanofluid, using CuO and TiO2 nanoparticles and water-ethylene glycol (RC) as base fluids on a radiator. The mass concentration of the hybrid nanoparticles varied from 0.25 %, 0.30 %, and 0.35 %. For the preparation of the hybrid nanofluid through a two-step method, by mixing dry samples of CuO and TiO2 nanoparticles (50:50) and then the mixture of radiator coolant, RC (60 % water and 40 % ethylene glycol). The fluid flow varies from 20 liters per minute to 28 liters per minute. Temperature variations range from 70 °C to 90 °C by using controlled heating. Four thermocouples measure the inlet and outlet hot fluid flow and the airflow before and after the radiator. The experiment showed that the overall heat transfer coefficient increases remarkably with the increase of the hybrid nanoparticle concentration under various flow rate values. The maximum overall heat transfer coefficient increases by about 83 % compared to pure radiator coolant under 0.35 % mass concentration at a flow rate of 22 liters per minute and a temperature of 70 °C. It has also been found that the heat transfer rate is highly dependent on the radiator's mass fraction and flow rate. Increasing the mass concentration shows maximum enhancement in heat transfer rate. Inlet temperature also enhances the heat transfer rate, but its effect is small compared to nanofluid's mass concentration and flow rate. This study reveals that hybrid nanofluids can be suitable as a working fluid, especially in small-scale heat transfer devices.
Sugeng Hadi Susilo, Listiyono Listiyono, and Khambali Khambali
Private Company Technology Center
The increasing demand for diesel fuel causes high levels of air pollution, noise, and vibration. Therefore, we need a mixture of materials that can reduce the environmental effect with low vibration. The purpose of this study was to investigate the effect of a diesel-essential oil mixture on a diesel engine, related to engine performance, noise, and vibration. The research was conducted using a 402 CC Dongfeng diesel engine, a mixture of diesel and essential oils with a percentage of 5 %, 10 %, 15 %, 20 %, engine speed of 1,300 rpm, 1,500 rpm, 1,700 rpm, 1,900 rpm. The noise intensity test uses a sound level meter at 30–130 dBA with a frequency between 20–20,000 Hz. To test the density of smoke, a smoke tester was used. Meanwhile, to measure the rotational speed of the engine, a DT 2234L type tachometer was used. A digital stopwatch was used to measure the processing time with an accuracy of up to 0.01 s. Besides that, a strain gauge was also used to detect vibrations. A measuring cup was used to measure the volume of the mixture of fuel and essential oils. The results showed that in the B10 mixture at 1,300 rpm engine speed, the largest fuel consumption time was 155 s. While the smallest fuel consumption time is found at 1,900 engine speed, which is 106 s. The lowest percentage of exhaust emissions is in the B20 mixture, which is 56.8 %. While the largest percentage of exhaust emissions is in B0 with a value of 79.8 %. The lowest noise value is in the B10 mixture at 1,300 rpm engine speed, which is 105.7 dB. While the highest noise value is at 1,900 engine speed, which is 112.3 dB. The lowest vibration is in the B10 mixture with an engine speed of 1,300 rpm, which is 975.7 Hz. While the highest noise value is in the B10 mixture with 1,900 engine speed, which is 989.8 Hz.
Akhmad Suryadi, Qomariah Qomariah, and Sugeng Hadi Susilo
Private Company Technology Center
The demand for self-compacting concrete is very high because this concrete has high flowability and has resistance to segregation. Natural aggregates are of high value, while concrete demolition materials are abundant and of low value. So that the recycled coarse aggregate can be used as concrete material, this study analyzes the characteristics of Self Compacting Concrete (SCC) using recycled coarse aggregate from construction waste. Tests for aggregate wear, aggregate hardness, compressive strength of concrete and tensile strength of concrete were carried out. The wear test refers to the standard AASHTO T-96-74, ASTM C-131-55 and SNI 2417-2008. This test uses recycled coarse aggregate that has been washed so that the sludge content is clean; after that, it was baked with the used aggregate, the aggregate that passed the 12.5 mm sieve and was retained in the 9.5 mm sieve. The test object is pressurized 40 tons at a speed of 4 tons/minute. Concrete Compressive Strength Test refers to SNI 03-1974-2011, using a scale with an accuracy of 0.3 % of the weight of the concrete, a concrete press machine and a capping machine. While the split tensile strength test of concrete refers to SNI 03-2491-2014, carried out on days 7, 21 and 28 with a cylindrical test object. Variations of recycled aggregates start from 0 %, 25 %, 50 %, 75 %, and 100 %. The design's compressive strength is 25 MPa. The results showed that the recycled aggregates had good gradation, high absorption and low specific gravity compared to natural aggregates. The recycled coarse aggregate reduces the compressive strength of the concrete and causes a decrease in a slump, thereby reducing the split tensile strength of the concrete
Susilo Hadi, Asrori Asrori, and Gumono Gumono
Centre for Evaluation in Education and Science (CEON/CEES)
The article discusses the efficiency analysis of the Photovoltaic (PV) modules, namely polycrystalline and amorphous. The performance in question is the instantaneous efficiency obtained from the measurement of the voltage (V) and current (I) data generated by the two PV modules. In addition, it aims to determine the effect of solar radiation on the output power of polycrystalline and amorphous PV modules. The research was conducted in September 2020, with the outdoor location of the Department of Mechanical Engineering, State Polytechnic of Malang (7,944 °S; 112,613 °E). The independent variables in this study are the current and voltage generated, and the type of PV Module (Polycrystalline and Amorphous). The dependent variable in this study is the actual power and instantaneous efficiency. Measurement of solar radiation using the Glentest SM 206 Solar Power Meter. Measurement of Current and Voltage using a Digital V-I Meter. The results showed that the greater the solar radiation, the higher the actual power and efficiency generated by the PV Module. Polycrystalline PV Modules are capable of producing higher average actual power and average instantaneous efficiency, which are 86.83 W and 11.92% when compared to Amorphous PV Modules, which are 43.88 W and 6.01%.
Sugeng Hadi Susilo and Hangga Wicaksono
OU Scientific Route
A further investigation of premixed biogas combustion towards the NOx formation is presented in this study. The purpose of the simulation is to determine the addition of CO2 in biogas fuel to the combustion behavior of premixed biogas on NOx formation, and to determine the occurrence of NOx in the pre-mixed biogas combustion. In this study, the Counterflow Premixed Flame class is used where this class is based on the One Dim class which is the basis for simulations with a 1-dimensional domain. The Counterflow Premixed Flame class uses an axisymmetric stagnation flow domain which has been written based on the equations. Cantera uses Newton's method to solve them. Completion is carried out in two stages. The first stage is to solve the solution using the equilibrium at each z coordinate point that has been determined. Many estimation starting points are determined from the start of the program. The second stage is the recalculation process at each point and then subdivided to get a smoother solution. The premixed excess CO2 biogas fuel and air combustion analyzed using a 1-dimensional numerical study. The diluted CO2 mass fraction ranged between 0–40 %. The CH4/CO2/air volume flow rate was maintained in ±L/min. The analysis implements the 1-D Counter Flow approach. Two counterflow nozzles were 20mm in diameter and the flame stagnation point at 10 mm. The results show that NOx mass fraction formed only on a fuel-lean mixture of CH4/CO2/air and its values decreased along with CO2 added. The addition of CO2 could reduce the NO species mass fraction down to 18 %, and NO2 reduction down to 7 %. This is mainly caused by a decreasing heat release rate of NO+N↔N2+O, N+O2↔NO+O, N+OH↔NO+H, and N+CO2↔NO+CO reactions. The N+CO2↔NO+CO reaction increased as CO2 was added but its values were not as much as the decline of three other reactions
Sugeng Hadi Susilo and Agus Setiawan
OU Scientific Route
The paper discusses the performance of the pump in relation to the impeller. The impeller section is determined by the number and angle of the blades. Therefore, the purpose of this study was to analyze the role of the number and angle of impeller blades on the performance (discharge and discharge pressure) of centrifugal pumps based on experiments and simulations.
 The method used is experiment and simulation. Using a centrifugal pump type GWP 20/4 SW, Maximum Output: 6.5 HP/3500 rpm, Inlet/Outlet: 2 Inch, Dimensions: 475x375x370 mm. Experiments and simulations by varying the number of blades 2, 4, and 6 with a blade tilt angle of 130°, 150°, and 160°. For flow simulation using solid works program.
 The results show that pump performance is related to discharge pressure, impeller with 2-blades and an angle of 130° the pressure increases 0.45–2.45 bar, for 150° increases 0.14–2.96 bar, and 160° increases 0.29–3.07 bars. For a 4-blade impeller and an angle of 130°, the pressure increases by 0.48–3.12 bar, for 150° it increases by 0.39–3.39 bar, and for 160° it increases by 0.36–3.48 bar. While the impeller for 6-blades with an angle of 130° the pressure increases from 0.6 bar to 3.72 bar, for 150° increases from 1.36 to 4.34 bar, and 160° increases by 0.36–4.74 bar. While it related pump performance to flow rate, increasing the number of blades causes a decrease in flow rate. The highest flow rate is in a 2-blade impeller with a blade angle of 130° is 404.91 l/s. The lowest flow rate is on a 6-blade impeller with an angle of 160° is 279.66 l/s
Prayitno Prayitno, Sri Rulianah, Windi Zamrudy, and Sugeng Hadi Susilo
Private Company Technology Center
The cassava starch wastewater contains organic materials (as BOD, COD) in high concentrations so it has the potential to cause pollution in the aquatic environment. Several methods of cassava starch wastewater treatment have been used to reduce the concentration of organic matter (pollutants) in cassava starch wastewater, including Activated Sludge, Stabilization Pond, Anaerobic-Aerobic filter process. However, various studies continue to be carried out to get higher processing efficiency on the factors that influence it. Several factors influence the efficiency of wastewater treatment processes, including the type and origin of decomposing microorganisms, hydraulic residence time (HRT), organic load rate (OLR), process design, pH, and temperature. The research aimed to evaluate the performance of the AnF2B reactor in treating cassava starch wastewater, in which the reactor performance is shown by changes in organic matter removal (COD removal) and biogas production. The research is conducted using 3 types of AnF2B reactors wherein each AnF2B reactor contains a bee nest-shaped bio-filter as a growth medium for the consortium of indigenous bacteria. The AnF2B reactor operates in anaerobic conditions with a set temperature of 29–30 °C and a pH of 4.5–7. In each AnF2B reactor, cassava starch wastewater is fed with different OLR so that each reactor has an HRT of 5, 6, and 7 days. The concentration of COD at the influent and effluent of the reactor was measured and the biogas was produced using the APHA standard method. The results showed that the AnF2B reactor had a satisfactory performance in COD removal and biogas production, which at HRT: 6 days and OLR of 1.72 g/L·day found that the maximum COD removal was 98 % and the volume of biogas of 4.8 L/L·day was produced on the 12th day
Agus Tugas Sudjianto, Aji Suraji, and Sugeng Hadi Susilo
Private Company Technology Center
Expansive clay is one of the problems in construction work. The soil has the characteristics of being easy to expand when exposed to water, causing a decrease in the strength value of the soil. The can be overcome by stabilizing the soil. The soil is formed from weathering and contains the mineral montmorillonite. The soil is very sensitive to moisture content, has a high shrinkage rate, thus interfering in construction work. Therefore, additional materials are needed to overcome the problem, one of which is soil stabilization. The study aimed to stabilize the expansive clay soil. This is done by analyzing the physical and mechanical properties of expansive clay with a shell ash mixture. Expansive clay is taken directly (undisturbed) or disturbed. Undisturbed soil is taken using a tube, so that the soil is not disturbed by outside air, while disturbed soil is taken using a shovel and then put into a sack container. Expansive clay stabilization method lies in adding the percentage of shell ash mixture (5 %, 10 %, 15 %, and 20 %). The soil, the initial moisture content (γd) of which has been determined, is mixed, then molded into a cylindrical shape. The mold was stored in a desiccator, then watered with 5 % water every day until the soil became saturated. Then, using a Proctor test, chemical tests (soil chemical test, soil mineral test), physical tests (soil moisture, Atterberg limit), and mechanical tests (unconfined compression test, compaction test, swelling test) were carried out. The results showed that the addition of an oyster shell ash stabilizing agent to expansive clay affected the physical and mechanical properties of the soil. The addition of shell ash can reduce soil moisture with various plasticity indexes. While the soil stress value decreased, the swelling of the soil increased significantly above the original soil.
Sudarmadji Sudarmadji, Santoso Santoso, and Sugeng Hadi Susilo
Private Company Technology Center
The paper discusses the combined methods of increasing heat transfer, effects of adding nanofluids and ultrasonic vibration in the radiator using radiator coolant (RC) as a base fluid. The aim of the study is to determine the effect of nanoparticles in fluids (nanofluid) and ultrasonic vibration on the overall heat transfer coefficient in the radiator. Aluminum oxide nanoparticles of 20–50 nm in size produced by Zhejiang Ultrafine powder & Chemical Co, Ltd China were used, and the volume concentration of the nanoparticles varied from 0.25 %, 0.30 % and 0.35 %. By adjusting the fluid flow temperature of the radiator from 60 °C to 80 °C, the fluid flow rate varies from 7 to 11 lpm. The results showed that the addition of nanoparticles and ultrasonic vibration to the radiator coolant increases the overall heat transfer coefficient by 62.7 % at a flow rate of 10 liter per minute and temperature of 80 °C for 0.30 % particles volume concentration compared to pure RC without vibration. The effect of ultrasonic vibration on pure radiator coolant without vibration increases the overall heat transfer coefficient by 9.8 % from 385.3 W/m2·°C to 423.3 W/m2·°C at a flow rate of 9 liter per minute at a temperature of 70 °C. The presence of particles in the cooling fluid improves the overall heat transfer coefficient due to the effect of ultrasonic vibrations, nanofluids with a volume concentration of 0.25 % and 0.30 % increased about 10.1 % and 15.7 %, respectively, compared to no vibration. While, the effect of nanoparticles on pure radiator coolant at 70 °C enhanced the overall heat transfer coefficient by about 39.6 % at a particle volume concentration of 0.35 % compared to RC, which is 390.4 W/m2·°C to 545.1 W/m2·°C at 70 °C at a flow rate of 10 liter per minute
Aji Suraji, Ludfi Djakfar, Achmad Wicaksono, Marjono Marjono, Leksmono Suryo Putranto, and Sugeng Hadi Susilo
Private Company Technology Center
Public transport safety is still an issue that needs to be studied by bureaucrats and researchers. This is because public bus accidents are still quite high. This is because many families, involved in traffic accidents, are shocked by the accident. Therefore, the problem of perception of a safe bus needs to be studied. The purpose of this study was to determine the perception model of a safe public bus. Mathematical modeling based on the parameters that have been studied was selected first. While the second objective was to determine the importance value of the parameters that are an indication of the perception of the safety of intercity bus public transportation. This research is a type of perceptual one where the data is taken from the relevant respondents. The method of data collection was carried out using a questionnaire with respondents from bus company owners, drivers, and passengers in the province of East Java, Indonesia. Respondents were asked to answer questions related to the variables of income, speed, comfort, and safety. The method of conjoint analysis is used. The first stage is the result of modeling the perception of a safe bus. Further analysis is carried out to obtain the importance value of the parameters. The result of this research is a utility model for the perception of a safe bus, which is expressed by the equation U, where the variables include income, speed, comfort, and safety. The highest level of importance is income 33.29 %, followed by the security variable with a weight of 25.39 %. This shows that the income factor is a top priority for drivers and management of bus company owners, while road safety is second only to income. In other words, respondents' perceptions are more concerned with income, while safety is still a non-priority factor.
Agus Tugas Sudjianto, Abdul Halim, Oktiono Gembiranto, and Sugeng Hadi Susilo
Private Company Technology Center
The paper discusses the comparison of fly ash with Lapindo mud as a land stabilizer for a landfill in Pasuruan, Indonesia. Land for landfills has a low level of stability due to the condition of garbage that has accumulated and undergoes a process of decay. This land condition is less favorable to support the construction of the building above it if one day the location is used for construction. Therefore, it is necessary to stabilize the soil first. The purpose of this study was to determine the effect of adding a mixture of TPA soil with fly ash and Lapindo mud. The method used by sieve testing and compaction of the specimens for each treatment consisted of a mixture of TPA soil with fly ash and TPA soil with Lapindo mud, while the percentages of fly ash and Lapindo mud to the dry weight of the original soil were respectively 0 %, 10 %, 15 %, and 20 %. The results showed that stabilization of the landfill with fly ash reduced the silt content while stabilization with Lapindo mud increased the levels of silt in the landfill so that fly ash was better than Lapindo mud for stabilization of the landfill. The specific gravity values for both stabilization mixtures increased equally. Based on the results of the standard compaction test for the addition of a mixture of fly ash, the OMC value decreases and the greater the value of dmaxs indicates that fly ash is good for landfill stabilization, while the addition of a mixture of Lapindo mud increases the OMC the smaller the value of dmaxs. For the direct shear test of the two mixed soils, the value of the internal friction angle (Æ) increased. The percentage value of the optimum mixture of mixed soil+fly ash is 14 % with an internal shear angle (Æ) of 38°, while the stabilization of landfill with Lapindo mud obtained the optimum mixture percentage value of 11 % with an internal shear angle (Æ) of 31°
Sugeng Hadi Susilo, Asrori Asrori, and Gumono Gumono
Private Company Technology Center
The paper discusses the effect of the stirrer and container rotation direction on the mixing index (Ip). The chaos theory is the result of an in-depth study of various problems that cannot be answered by the two previous major theories, namely quantum mechanics and the theory of relativity. Effective mixing of the flow area does not depend on rapid stirring. This study uses a container with a double stirrer, camera, programmable logic controller, tachometer, 6 A adapter, and a computer. DC electric motor (25 V) for turning stirrers and housings. The diameter of the primary and secondary stirrers is Dp=38 mm and Ds=17 mm. The diameter of the container made of transparent plastic is Dw=160 mm and height is 170 mm. Primary stirrer rotation (np)=10 rpm, secondary stirrer rotation (ns)=22.3 rpm, and container rotation (nw)=13 rpm, the angular velocity of the container is Ww=360° while the angular speed of the primary stirrer is Wp=180°. The liquid consists of a mixture of water and paint (white). For dye, a mixture of water and paint (red) is used. For testing the Brookfield viscometer, the viscosity of the liquid and dye is used. The results showed that turning the stirrer in the opposite direction to the container, there will be stretching, bending, and folding around the stirrer, and the smallest mixing index was P2V-b (0.94). In addition, based on the mixing index value above, the highest mixing effectiveness level is obtained, namely: P2V-b, P2S-b, P2B-b, P2V-a, P2B-a, and finally P2S-a. The mixing index is inversely related to the effectiveness level. So the highest effectiveness level is given by the following treatment: 1. Variation rotation (between opposite rotating mixers), 2. Opposite rotation (stirrer rotation opposite direction to the container), 3. Unidirectional rotation (stirrer rotation in the direction of the container)
Sugeng Hadi Susilo and Asrori Asrori
OU Scientific Route
Turbulent mixing can damage the material molecules because of turbulence. Whereas laminar mixing raises a problem when mixing is carried out on viscous liquids. The mixing mechanism using chaotic flow affects the mixing quality. The aim of the experiment was to determine the position and direction of the double stirrer chaotic mixer. The installation of a chaotic mixer uses a cylindrical tub and two different mixers consisting of a primary mixer (Pp) and a secondary mixer (Ps). Periodically rotate the container and stirrer. The center of the vessel and primary mixer are placed at the same coordinates. For ε=4 cm (Pp to Ps distance), there are three experiments, namely: vessel rotation and directional stirrer (P2S-a), vessel rotation and opposite stirrer (P2B-a), and vessel rotation, both primary and secondary stirrers are directional variations. (P2V-a). Eccentricity 7 cm, there are also three treatments as above: one direction (P2S-b), reverse direction (P2B-b), and variation of direction (P2V-b).
 The video camera recordings are processed digitally. Qualitative data show a pattern of behavior during mixing. Meanwhile, quantitative data is used to determine the level of mixing effectiveness. The results showed that the direction of rotation of the two cylinders had no effect on the effectiveness of chaotic mixing. Based on the number of initial droplets of dye, the treatment that experienced the fastest chaos was P2B-b, at n=2 and r=3.5303. The difference in the number of color droplets does not affect chaotic behavior. The highest mixing efficiency was generated by the lowest P2V-b mixing index value of 0.94. Simultaneously, the direction between the mixer and the container will provide maximum mixing efficiency. Isolated mixing areas (island) and areas of poor mixing occur because of one-way rotation and low eccentricity
S H Susilo, Z Jannah, L D Mustofa, and Y Effendhi
IOP Publishing
Abstract The increasing energy demand is in line with population growth as well as the development of science and technology, and the maximum utilization of energy derived from magnets. The purpose of this research is to design of permanent magnet motor that produces rotation that can be utilized as power plant propulsion, without using fuel oil. The method used is to examine and search the gap of existing patent design and develop it in the form of a new design, In the hope of increasing the potential of magnetic energy into a magnetic power plant. By designing the magnetic position and angle of attack on the rotor and stator motor magnet.