Lontar Jurnal Teknik Mesin Undana (LJTMU)

8 – 17

Authors: Jusuf B. Tododjahi, Kristomus Boimau, Ishak S. limbong

Analysis model of the mechanical behavior of polymer composite materials- are often by the researchers on the adoption of environmental conditions (hygrothermal) shown are constant. But in reality, the application of composite materials are often in constant environmental conditions or the ever-changing as the wind turbine blade, the plate and the fish cooler made of fiber glass boat that has always under the conditions of humidity and temperature changes Worked. The aim of this study is of to determine the effect of the immersion of the tensile properties and bending properties of the glass fiber composites with 40 % fiber volume fraction (Vf). In this study, the materials used are glass fibers and polyester resin. Tensile tests were according to ASTM D638, while the standard ASTM D790 for bending test. The test specimen molded by hand lay-up method, followed by pressure and left for 24 hours. In the following, the combined term average on standard train and bending test, the test samples were different treatments that immersion in water and sea water for 30 days and in an open environment (on the roof of the house) left. Tensile and bending testing process conducted shortly after the specimen are remove from the water, weighed know by bending tests first to determine the percentage of water absorption. The results of the composite percentage of water content tends to increase with the long of immersion time, but the increase only 0.0145 % for the bending test and 0.0166 % for the tensile specimens. While the test results show that the train - samples were soaked in water for 30 days had the lowest tensile strength of 84.47 MPa, while the highest tensile strength of 176.80 MPa obtained on the test specimens without immersion treatment. The results also show that the bending test specimen is immersed in water for 30 days had the lowest flexural strength, receive equal 113.77 MPa, while the highest bending strength of 279.40 MPa to specimens with out treatment. The results show a macro photo facture brittle debonding and delamination in the bending specimens, as well as the tensile test specimens,seen a brittle facture, debonding and delamination

26 – 33

Authors: Jahirwan Ut Jasron

Corrosion attack can not be prevented, but we can control so that the structure of the components have a longer life, one way to inhibit the rate of corrosion is by way of coupling (decouplet) was a kind of metal to form a simple wet corrosion cell. In a study made, used metal steel, aluminum, brass with a length of 6 cm, width 2.5 cm, thickness 3 mm and 4 mm diameter bolt holes, having done the research process by way of corrosion rate immersed in sea water from each place the container on its own steel-aluminum, aluminum-brass-brass and steel separate individual. Time variation of the corrosion test is 408 hours, 744 hours, 1080 hours, 1416 hours, 1752 hours and 2088 hours. The results achieved corrosion steel-aluminum: 408 hours corrosion time of steel 0.009 mm-year and increased 0.02 mm-year at 2088 hours, 408 hours of corrosion when aluminum 0.1 mm-year and decreased 0.05 mm-year at 2088 hours, aluminum, brass: aluminum corrosion time of 408 hours 0.08 mm-year and decreased 0.04 mm-year at 2088 hours, the corrosion of brass 408 hours 0.02 mm-year and decreased 0.01 mm-year at 2088 hour, steel-brass: steel corrosion time of 408 hours 0.10 mm-year and decreased 0.04 mm-year at 2088 hours, 408 hours of corrosion of the brass 0.009 mm-year and increased 0.01 mm-year at 2088 hours. Great influence on the rate of corrosion galvanic series of low alloy steels, aluminum alloys and aluminum brass decouplet unfit for low alloy steels and aluminum alloys because it has close proximity to the series while decouplet aluminum alloys brass aluminum and steel alloys decouplet low aluminum brass decouplet should not be, because it has a long way in the series.

40 – 46

Authors: Marleni Margreth Nino, Ishak Sartana Limbong, Ben Vasco Tarigan

Vaccination is one of important ways to against this is and to make life longer. So, it makes cattle have production higher and grow them better. The problem is when the vaccine should carrier more than two hours. The temperature of vaccine will arise event it carrier with ice box. There are so many research had been done to keep that stabile. One of the researches is using peltier element as a heat pump. It used doable peltier and heat sink-fan to keep vaccine chamber temperature between 2-8 oC. In this research is using double element peltier too to pump heat and using polyvinylchloride(PVC) for vaccine carrier material that have low heat conductivity. We used thermocouple and DAQ to monitor temperature changing of vaccine that had been put in the carrier. From this research we found that temperature of vaccine can be hold between to the allowing temperature when in take power about 72 Watt.

59 - 65

Authors: Donni Pa, Yeremias M. Pell, Wenseslaus Bunganaen

This aims to determine the characteristics of the widuri fiber (Calostropis Gigantea) as a composite reinforcement. The study is divided into several stages the first stage of making fiber based on physical characteristics before flowering, during flowering, and fruiting moment. And fiber is divided into two, the untreated fibers and fibers treated with 5 % NaOH for 1 hour, 2 hours, and 3 hours. Water content on the fiber missing ascertained by means of the fiber was heated in an oven for 3 hours at a temperature of 105 0C. The next stage is calculated fiber density, fiber diameter and fiber tensile properties widuri. From the research, obtained the highest fiber content of water in the fiber before flowering conditions on the fiber without treatment with 12.40916 % value. Fiber diameter decreased after treated in fiber , with a diameter of 0057 mm is equal to the highest obtained in the fiber before flowering without treatment. Fiber tensile strength also decreased with the highest value of 428 979 MPa in the fiber without treatment at the time of fruit fiber conditions of 156 403 MPa while the lowest was obtained on NaOH -treated fibers 3 hours on the conditions before flowering. Good observation on an optical microscope photograph and SEM image, the results showed that treatment with 5 % NaOH to make the fiber surface be clean and the smaller diameter. This is due to the NaOH treatment, the content of lignin, wax and other impurities to be lost from the fiber surface. From this information, it can be concluded overall widuri fibers can be developed into a composite reinforcement with polyester matrix.

72 – 81

Authors: Verdy A. Koehuan, Laurensius Nogur, Jahirwan Ut Jasron

Contra Rotating wind turbine is a horizontal axis turbine has two rotors rotating in opposite directions on the same axis giving and receiving power so that it can operate well at low wind speeds. In this study carried out by determining the variation in the angle of the blade, i.e. each angle of 0º, 5º, and 10º on the two rotors with a diameter of 0.50 m, respectively, and 0.30 m at a position opposing the rotor blade. The purpose of this study was to determine the effect of the variation of the rotation angle blade turbine (rpm), torque (T) and power coefficient (Cp) and the efficiency of the turbine at any wind speed variations. Wind speed influence on the output power or mechanical power, rotation of the rotor and the rotor thrust force, the lowest output power 7.396 watts at wind speed of 4.03 m/s, the highest output power of 25.397 Watts at wind speeds of 6.08 m/s, lowest rotor rotation to 727 rpm with no load on the wind speed of 4.03 m/s at an angle of 0º blade, rotor rotation 1153 rpm at the highest wind speed of 6,08 m/s at an angle blade10º. Rotor thrust 450 gr at the lowest wind speed of 4.03 m/s at an angle of 0º, the highest 750 gr rotor thrust on wind speed of 6,08 m/s at an angle of blade 10º. The change in the angle of the wind turbine blade shaft Contra rotating horizontal models, the power coefficient (Cp) generated from the turbine work increases with the angle with Cpmaks 0.701 at TSR 4.275 for 10º angle.