Scientific Journal of Mechanical Engineering Kinematika

ANALYSIS OF SAND-CASTING SPUR GEAR FROM ALUMINUM 1100 AND 6063 TOWARDS MECHANICAL PROPERTIES

2024-07-19T12:51:25+00:00

Spur gear is a toothed-shaped machine component which works by friction each other to transmit high efficiency rotational movement on shafts. This requires spur gear to possess robust mechanical properties. The sand-casting technique is widely known as a simple manufacturing process to produce high quality mechanical products with less failure. Moreover, aluminium is an alloy which owns good mechanical properties, corrosion resistance and castability. Hence, the research aims to conduct manufacturing process of spur gear using sand-casting technique made from 1100 and 6063 aluminium which followed by comparing mechanical characteristics of hardness and wear resistance. The casting process initially begins by designing and fabricating patterns, then preparing the mold and silica sand along with the aluminium melting process at temperature 600^oC in a furnace, which ends by pouring the molten aluminium into the sand mold. After the spur gear was obtained, mechanical testing was examined to evaluate its hardness and wear resistance values. From the results, it was clearly found that spur gear product made from aluminium 6063 possess high hardness value (58.4 HV) and the lowest wear rate reduction (0.000827 mm3/minute). Thus, spur gear made from 6063 aluminium has the best mechanical characteristics which affects long lifespan.

THE INFLUENCE OF IGNITION TIMING AND INJECTION DURATION USING ARDUINO-BASED ECU ON THE PERFORMANCE OF A 110CC FI ENGINE

2024-09-14T03:08:32+00:00

The advancement of automotive technology in Indonesia has been rapid, particularly in motorcycle production, which reached 5,057,516 units in 2021 according to AISI data. Manufacturers now introduce models equipped with injection ignition systems using Electronic Control Units. These ECUs control actuators based on the inputs they receive. Arduino-based programmable ECUs are available to improve performance by adjusting ignition timing and fuel injection duration. This research aims to determine the impact of these adjustments on the torque, power, and fuel consumption of 110-cc FI motorcycle to find the best variations for optimal results. An experimental method was used, testing the Arduino-based programmable ECU against the standard ECU on 2014 Honda Vario 110-cc FI. Tests included variations in ignition timing of +2⁰, +4⁰, +6⁰, +8⁰, +10⁰ degrees before TDC from the standard and fuel injection duration variations of +5%, +10%, and +15%. The highest torque was achieved with ignition timing variation of +4⁰ degrees and injection duration of +5%, reaching 16.98 N.m. Maximum power was observed at +20 degrees timing and +10% injection, reaching 7.03 horsepower. Optimal fuel consumption was found at ignition timing of +2⁰ degrees and injection duration of +5%, with rate of 4.15 ml/min, compared to the standard ECU.

ANALYSIS ALKALIZATION HYBRID COMPOSITE ALABIO DUCK FEATHERS AND PURUN RAT FIBER ON WEAR AND HARDNESS

2024-07-22T01:37:11+00:00

South Kalimantan Province is the habitat for a type of plant known as Purun Tikus. This plant is traditionally used for handicrafts and serves as a habitat for Alabio ducks. Sodium hydroxide (NaOH) is an alkaline chemical compound that effectively removes and cleans residues in fibers. Therefore, this study investigates the composite materials reinforced with duck hair and Purun Tikus using an immersion alkalization method with NaOH. The objective of this research is to determine the effects of alkalization on a hybrid mixture of duck hair and Purun Tikus with a polyester matrix on wear and hardness properties, and to examine the influence of voids on perforated pores. The wear test was performed according to ASTM G99-04, and the hardness test followed the ASTM D-785 standard. Samples were prepared using the hand lay-up method with a composition of 78% polyester, 2% catalyst, and 20% reinforcement with a volume ratio of (10%:90%). The alkalization treatment times were set at 10, 20, 30, 40, 50, and 60 minutes using a 5% NaOH solution. The results indicated that the highest wear value was observed at the 10-minute alkalization time, while the lowest wear value was noted at the 60-minute alkalization time. Conversely, the highest hardness value was obtained at the 60-minute alkalization time, and the lowest at the 10-minute alkalization time. Therefore, alkalization time significantly affects the wear, hardness, and void properties of the composite materials.

AIRFLOW PATTERNS IN A HELICAL SAVONIUS WIND TURBINE WITH VARIATIONS BLADE NUMBERS USING CFD METHOD

2024-09-14T04:03:19+00:00

The availability of fossil resources is decreasing, cause government and private sectors to race in developing renewable energy. One solution is to create Wind Power Plants to meet energy demands. The Savonius turbine, also known VAWT, this great potential to meet small-scale energy needs. Savonius turbines have lower performance compared to other types. This performance needs to be enhanced through design modifications, such as varying the number of blades. This research purpose is to analyze effect number of blades on performance of helical Savonius turbines. This research focuses on airflow patterns with varying blade numbers in helical Savonius turbines. These turbines numerically studied using Computational Fluid Dynamics (CFD) approach with ANSYS Fluent. Each variation of blade numbers will simulate at wind speeds between 1 to 5 m/s. Numerical testing results will provide visualizations in form contour and vector within pressure or velocity scope for each variation. Based on visualization of numerical testing results, found that number of blades affects flow patterns. Increasing the number of blades increases turbulence flow. Pressure on convex surface also increases with the addition of blades. These two airflow phenomena reduce turbine performance, so two blades produce most optimal performance due to minimal resistance they experience.

DEFECT DETECTION IN CARBON FIBER REINFORCED POLYMER USING PEARSON CORRELATION COEFFICIENT FROM ULTRASONIC ECHO SIGNALS

2024-09-14T05:00:05+00:00

Carbon fiber reinforced polymer (CFRP) is a composite material widely used in the aerospace, automotive, and marine industries due to its high strength and low weight. However, the reliability of CFRP can be compromised by internal defects occurring during manufacturing or use. This study aims to detect defects in CFRP using the Pearson correlation coefficient from ultrasonic echo signals. This method utilizes ultrasonic waves to identify defects based on changes in signal patterns. The reference signal is obtained by averaging the signals from several defect-free locations. Variations in the measurement signals compared to the reference signal are quantified using the Pearson correlation coefficient to classify defect-free and defect-containing areas. The test samples consisted of thin CFRP plates with artificial defects created using Teflon material in the form of circles with a radius of 15 mm, placed at two different depths. The results indicate that the Pearson correlation coefficient effectively distinguishes between defect-free and defective areas. Defect-free areas showed correlation values in the range of 0.97 to 1, while defective areas showed low correlation values in the range of 0 to 0.36.

ULTRASONIC-BASED NON-DESTRUCTIVE TESTING SYSTEM FOR QUALITY CONTROL IN FABRICATION OF LEAD BRICK

2024-09-14T04:57:14+00:00

BATAN has the authority to improve the quality of lead brick production, which is still fabricated conventionally. Therefore, a non-destructive testing system has been developed, consisting of a Partial Immersion Technique transducer used to maintain a perpendicular scanning angle due to the uneven surface of the lead brick, an un0rick board used for its flexibility and good capability in generating high-voltage electrical pulses and high sampling frequency, and a laptop. The result is the optimization of ultrasonic parameters, with a transducer frequency of 500 KHz and a pulse length of 0.5 Î¼s. Additionally, tests were conducted on three cases. A standard lead brick used as a reference has a propagation speed of 2.156 m/s. The lead brick with artificial defects had the first defect location estimated at 23.32 mm with an error of 16.62%, the second defect location estimated at 25.1 mm with an error of 0.44%, the third defect location estimated at 36.17 mm with an error of 9.57%, and the fourth defect location estimated at 9.38 mm with an error of 6.2%. The third case, a lead brick with natural defects, had the defect location estimated at 26.77 mm with an error of 1.08%.