Pub Date : 2023-03-31DOI: 10.20961/mekanika.v22i1.70959
H. Carvalho, Ridwan Ridwan, S. Sudarno, A. Prabowo, D. Bae, N. Huda
This study presents reviews of the failure criteria to capture the resulting response due to the catastrophe of ship collision and grounding using the finite element. Researchers have introduced several failure criteria, for instance, the DNV RP-C204 criterion, Germanischer Lloyd criterion, Peschmann, RiceTracey and Cockcroft-Latham (RTCL), Bressan-Williams-Hill (BWH) instability criterion, and Liu criterion. As in the mathematical formula, each criterion has a difference. The choice of failure criteria will depend on the simulation's specific requirements and the analysis's goals. Liu's criterion can be used to evaluate the failure of materials in ship collision simulations, for example, when large element sizes (i.e., 20 mm) are considered in the simulation.
本研究回顾了失效准则，以利用有限单元来捕捉由于船舶碰撞和搁浅灾难而产生的响应。研究人员介绍了几种破坏准则，如DNV RP-C204准则、德国劳埃德准则、Peschmann、rice - tracey和Cockcroft-Latham (RTCL)准则、bressanwilliams - hill (BWH)失稳准则和Liu准则。就像数学公式一样，每个标准都有不同之处。失效准则的选择取决于仿真的具体要求和分析的目标。Liu准则可用于评估船舶碰撞模拟中材料的失效，例如在模拟中考虑较大的元件尺寸(即20mm)时。
{"title":"Failure criteria in crashworthiness analysis of ship collision and grounding using FEA: Milestone and development","authors":"H. Carvalho, Ridwan Ridwan, S. Sudarno, A. Prabowo, D. Bae, N. Huda","doi":"10.20961/mekanika.v22i1.70959","DOIUrl":"https://doi.org/10.20961/mekanika.v22i1.70959","url":null,"abstract":"This study presents reviews of the failure criteria to capture the resulting response due to the catastrophe of ship collision and grounding using the finite element. Researchers have introduced several failure criteria, for instance, the DNV RP-C204 criterion, Germanischer Lloyd criterion, Peschmann, RiceTracey and Cockcroft-Latham (RTCL), Bressan-Williams-Hill (BWH) instability criterion, and Liu criterion. As in the mathematical formula, each criterion has a difference. The choice of failure criteria will depend on the simulation's specific requirements and the analysis's goals. Liu's criterion can be used to evaluate the failure of materials in ship collision simulations, for example, when large element sizes (i.e., 20 mm) are considered in the simulation.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126128392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-31DOI: 10.20961/mekanika.v22i1.63870
Agris Setiawan, Sapna Yusmania, Anton Sudiyanto
The aim of this research was to determine the mechanical strength of AISI 4340 steel after pack carburizing with variation of barium carbonate (BaCO3) and sodium carbonate (Na2CO3) as energizer. The various ratios of energizer: 40/60, 50/50 and 60/40 w/w%. Mechanical test was conducted to determine tensile (ASTM E-8), impact charpy strength (ASTM E-23), rockwell hardness number (ASTM E-18) and microstructure characterization (ASTM E-3). Both type specimens were temperature pack carburized is 950ºC and holding time is 3 hours. Results showed that specimen C has a lowest ultimate tensile strength mean values than the other specimens, which is 333.43±30.22 MPa. The results of the impact test showed that the lowest impact energy value is found in specimen C, which is 4.32 joules and the highest impact energy value is found in specimens without treatment, which is 15.80 joules. Based on microscope observation indicated that microstructure of specimen was martensite structure increase and the results of the hardness test was influenced by martensite phase, specimen C has the highest hardness compared to other specimens, which is 80.70 HRC while the untreated specimen is 56.90 HRC.
{"title":"Mechanical Properties Of Pack Carburized AISI 4340 With Variation Energizer Composition of Barium Carbonate (BaCO3) And Sodium Carbonate (Na2CO3)","authors":"Agris Setiawan, Sapna Yusmania, Anton Sudiyanto","doi":"10.20961/mekanika.v22i1.63870","DOIUrl":"https://doi.org/10.20961/mekanika.v22i1.63870","url":null,"abstract":"<div><table cellspacing=\"0\" cellpadding=\"0\" align=\"right\"><tbody><tr><td align=\"left\" valign=\"top\"><p>The aim of this research was to determine the mechanical strength of AISI 4340 steel after pack carburizing with variation of barium carbonate (BaCO<sub>3</sub>) and sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>) as energizer. The various ratios of energizer: 40/60, 50/50 and 60/40 w/w%. Mechanical test was conducted to determine tensile (ASTM E-8), impact charpy strength (ASTM E-23), rockwell hardness number (ASTM E-18) and microstructure characterization (ASTM E-3). Both type specimens were temperature pack carburized is 950ºC and holding time is 3 hours. Results showed that specimen C has a lowest ultimate tensile strength mean values than the other specimens, which is 333.43±30.22 MPa. The results of the impact test showed that the lowest impact energy value is found in specimen C, which is 4.32 joules and the highest impact energy value is found in specimens without treatment, which is 15.80 joules. Based on microscope observation indicated that microstructure of specimen was martensite structure increase and the results of the hardness test was influenced by martensite phase, specimen C has the highest hardness compared to other specimens, which is 80.70 HRC while the untreated specimen is 56.90 HRC.</p></td></tr></tbody></table></div>","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127078911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-03-31DOI: 10.20961/mekanika.v22i1.63026
Dinda Clara, F. Mikšík, B. Kusharjanta, T. Triyono, Aniddya Salsabila Kurnia Putri
In this study, an experimental investigation has been carried out to determine the effect of alumina (Al2O3) addition in joining polypropylene. Polypropylene is a thermoplastic material used most as a non-metallic material. One of the joining methods that can be applied in Polypropylene is Friction Stir Welding (FSW). The use of Al2O3 as a filler is to modify the polypropylene matrix's properties to improve the joint's quality. The Al2O3 powder with 99 9% purity was inserted along the polypropylene plates in the groove. This research analyzed the role of adding Al2O3 and tool rotation speed concerning the joints' quality. The experiment was performed under different values of tool speed rotation (204 rpm, 356 rpm, 620 rpm, and 1140 rpm) and the presence or absence of the addition of alumina powder. Then, the joint's quality is visually observed by optical macroscopy at the top and cross-section view. From macroscopic observations, adding alumina could make the visual of the joint look better and result in minimum defects than the joint without alumina addition. Instead, the increasing tool speed rotation helped the distribution of alumina during the welding process.
{"title":"Effect of Adding Al2O3 on the Macrostructure of Friction Stir Welding Polypropylene Sheet","authors":"Dinda Clara, F. Mikšík, B. Kusharjanta, T. Triyono, Aniddya Salsabila Kurnia Putri","doi":"10.20961/mekanika.v22i1.63026","DOIUrl":"https://doi.org/10.20961/mekanika.v22i1.63026","url":null,"abstract":"In this study, an experimental investigation has been carried out to determine the effect of alumina (Al2O3) addition in joining polypropylene. Polypropylene is a thermoplastic material used most as a non-metallic material. One of the joining methods that can be applied in Polypropylene is Friction Stir Welding (FSW). The use of Al2O3 as a filler is to modify the polypropylene matrix's properties to improve the joint's quality. The Al2O3 powder with 99 9% purity was inserted along the polypropylene plates in the groove. This research analyzed the role of adding Al2O3 and tool rotation speed concerning the joints' quality. The experiment was performed under different values of tool speed rotation (204 rpm, 356 rpm, 620 rpm, and 1140 rpm) and the presence or absence of the addition of alumina powder. Then, the joint's quality is visually observed by optical macroscopy at the top and cross-section view. From macroscopic observations, adding alumina could make the visual of the joint look better and result in minimum defects than the joint without alumina addition. Instead, the increasing tool speed rotation helped the distribution of alumina during the welding process.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133975586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.61624
H. Nubli, Fahri Setyo Utomo, H. Diatmaja, A. Prabowo, U. Ubaidillah, D. Susilo, W. Wibowo, T. Muttaqie, Fajar Budi Laksono
Mandakini Neo is an autonomous vehicle that was designed and built by the students of the Universitas Sebelas Maret, which was included in the Bengawan Unmanned Vehicle (UV) Roboboat Team to compete in the annual international Roboboat competition of 2021. This competition requires participants to complete several missions; one of the main missions is to move through two gates made from four poles using full automatic navigation, in order to continue on with the other missions. To complete the course, we used Pixhawk and GPS to allow the ship to run automatically, while minimizing the ship’s movement tolerance. The use of Mission Planner software for monitoring, and also for color and shape image processing to help with the reading of objects, along with a sensor fitted on the ship, allowed the mission to be completed. Mandakini Neo was made with the capacity, speed, and comfort of the ship in mind, as well as the ship’s hydrodynamic performance, stability, volume, structural integrity, and construction cost. Following its development we conducted tests of stability, maneuverability, and seakeeping in order to achieve the smallest possible resistance rate; for this purpose, we used the Savitsky method. The manufacture of the ship also required the choosing of the material, the use of the sensor, and also selection of an appropriate system. Finally, the design that we developed was a ship with a catamaran hull type, for which the dimensions had already been calculated, and the proper materials decided, and simple electrical components were able to be obtained for the sensor and the system.
{"title":"Design of the Bengawan Unmanned Vehicle (UV) Roboboat: Mandakini Neo","authors":"H. Nubli, Fahri Setyo Utomo, H. Diatmaja, A. Prabowo, U. Ubaidillah, D. Susilo, W. Wibowo, T. Muttaqie, Fajar Budi Laksono","doi":"10.20961/mekanika.v21i2.61624","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.61624","url":null,"abstract":"Mandakini Neo is an autonomous vehicle that was designed and built by the students of the Universitas Sebelas Maret, which was included in the Bengawan Unmanned Vehicle (UV) Roboboat Team to compete in the annual international Roboboat competition of 2021. This competition requires participants to complete several missions; one of the main missions is to move through two gates made from four poles using full automatic navigation, in order to continue on with the other missions. To complete the course, we used Pixhawk and GPS to allow the ship to run automatically, while minimizing the ship’s movement tolerance. The use of Mission Planner software for monitoring, and also for color and shape image processing to help with the reading of objects, along with a sensor fitted on the ship, allowed the mission to be completed. Mandakini Neo was made with the capacity, speed, and comfort of the ship in mind, as well as the ship’s hydrodynamic performance, stability, volume, structural integrity, and construction cost. Following its development we conducted tests of stability, maneuverability, and seakeeping in order to achieve the smallest possible resistance rate; for this purpose, we used the Savitsky method. The manufacture of the ship also required the choosing of the material, the use of the sensor, and also selection of an appropriate system. Finally, the design that we developed was a ship with a catamaran hull type, for which the dimensions had already been calculated, and the proper materials decided, and simple electrical components were able to be obtained for the sensor and the system.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133623930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.59487
W. E. Juwana, R. A. Rachmanto, Mugi Wiyono, Iwan Istanto
Increasing the compression ratio is an attempt to increase the efficiency and performance of the engine. The purpose of the study was to analyze the effect of changes in the compression ratio on engine performance. Tests using a single-cylinder Otto engine by comparing the performance of an enlarged compression ratio of 9.7:1 and 10.4:1 with a standard compression ratio of 9.0:1. The result of the research is that the compression ratio of 9.7:1 produces a peak torque of 7.51 Nm at 6000 rpm, a peak power of 5.30 kW at 8000 rpm, and the lowest BSFC is 0.146 kg/kW.h at 6000 rpm. Torque and power increased by 0.09 Nm and 0.28 kW, and BSFC decreased by 0.018 kg/kW.h compared to the standard compression ratio of 9.0:1. Using a compression ratio of 10.4:1 produces a peak torque of 7.69 Nm at 6000 rpm, a peak power of 5.38 kW at 8000 rpm, and the lowest BSFC is 0.116 kg/kW.h at 6000 rpm. Torque and power increased by 0.27 Nm and 0.36 kW, and BSFC decreased by 0.030 kg/kW.h compared to the standard compression ratio of 9.0:1.
{"title":"Experimental Study Influences Changes In Compression Ratio To Performance Of Single Cylinder Otto Engine","authors":"W. E. Juwana, R. A. Rachmanto, Mugi Wiyono, Iwan Istanto","doi":"10.20961/mekanika.v21i2.59487","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.59487","url":null,"abstract":"Increasing the compression ratio is an attempt to increase the efficiency and performance of the engine. The purpose of the study was to analyze the effect of changes in the compression ratio on engine performance. Tests using a single-cylinder Otto engine by comparing the performance of an enlarged compression ratio of 9.7:1 and 10.4:1 with a standard compression ratio of 9.0:1. The result of the research is that the compression ratio of 9.7:1 produces a peak torque of 7.51 Nm at 6000 rpm, a peak power of 5.30 kW at 8000 rpm, and the lowest BSFC is 0.146 kg/kW.h at 6000 rpm. Torque and power increased by 0.09 Nm and 0.28 kW, and BSFC decreased by 0.018 kg/kW.h compared to the standard compression ratio of 9.0:1. Using a compression ratio of 10.4:1 produces a peak torque of 7.69 Nm at 6000 rpm, a peak power of 5.38 kW at 8000 rpm, and the lowest BSFC is 0.116 kg/kW.h at 6000 rpm. Torque and power increased by 0.27 Nm and 0.36 kW, and BSFC decreased by 0.030 kg/kW.h compared to the standard compression ratio of 9.0:1.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"158 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127670828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.51493
M. Salim, M. Rafidya, Bintang Ramadhan, Elvira Wahyu, Arum Fanani, D. Ariawan, E. Surojo
This research examines the strength of the UPRs-Cantula composite with theaddition of filler microcrystalline cellulose (MCC). Composites were createdwith a volume fraction of 30% Vf and a 45° angle. This angle variation receivedthe same treatment as the others, including untreated, alkaline, and fumigation.The treatment time for alkali treatment was 6 hours, while the treatment timefor fumigation was 10 hours. The strength of each angle variation wasdetermined, as well as its treatment of tensile strength, modulus of elasticity,and Poisson's ratio UPRs-cantula composites. According to the results, thealkali treatment produced the highest tensile strength and elastic modulusvalues. The highest Poisson ratio value was discovered without treatment at a45°. The alkaline treatment yielded the highest tensile strength and modulus ofelasticity test results. The pullout fiber fracture dominated the untreatedcomposite fracture, whereas the fiber breakage fracture dominated the alkalinetreatment.
{"title":"Effect of Alkaline Treatment and Fumigation (Fumigation) on the Mechanical Properties of Fiber Unsaturated Polyester-Cantula Composite with Compression Molding Method","authors":"M. Salim, M. Rafidya, Bintang Ramadhan, Elvira Wahyu, Arum Fanani, D. Ariawan, E. Surojo","doi":"10.20961/mekanika.v21i2.51493","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.51493","url":null,"abstract":"This research examines the strength of the UPRs-Cantula composite with theaddition of filler microcrystalline cellulose (MCC). Composites were createdwith a volume fraction of 30% Vf and a 45° angle. This angle variation receivedthe same treatment as the others, including untreated, alkaline, and fumigation.The treatment time for alkali treatment was 6 hours, while the treatment timefor fumigation was 10 hours. The strength of each angle variation wasdetermined, as well as its treatment of tensile strength, modulus of elasticity,and Poisson's ratio UPRs-cantula composites. According to the results, thealkali treatment produced the highest tensile strength and elastic modulusvalues. The highest Poisson ratio value was discovered without treatment at a45°. The alkaline treatment yielded the highest tensile strength and modulus ofelasticity test results. The pullout fiber fracture dominated the untreatedcomposite fracture, whereas the fiber breakage fracture dominated the alkalinetreatment.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132453368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.64294
E. R. Mahmoud, A. Shaharoun, A. Aljabri, H. Almohamadi, M. Farhan
Although the economic value of glass products and its importance to the Saudi National Economy is vast, not much information is available about the current state of the art of the industry. Likewise little information is available about the geography, potential sites for mining sand as well as the evaluation of sand quality. This paper attempts to bridge this gap by presenting a feasibility study of fabricating normal glass and glass ceramics from Saudi Arabia’s domestically available raw materials. It discusses the current status of glass industry in Saudi Arabia and the Middle East region. It also gives a brief explanation about the sand topography in Saudi Arabia. In order to determine the feasibility of fabricating glass using these raw materials, experimental data on the fabrication of normal glass and glass-ceramics from indigenously available raw materials was obtained and reported as part of the findings of this paper Firstly, normal transparent glass were able to be fabricated without any apparent large defects using sand collected from Ar-Rayis region in Saudi Arabia. Four nano-sized crystallization catalysts, namely VC, WC, TiC and Y2O3, were added to the constituents of the glass in 3 wt.%. For VC, the crystallization process was limited. The glass ceramics of WC consisted of multi-dimensional edges crystals which covered all the matrix. Gray crystalline whiskers were obtained by addition of TiC. The Y2O3- glass ceramics consisted of multi-directionally rosette crystals. Finally, the microhardness values of the added crystallization catalysts glass ceramics were obtained and found to be much higher compared to normal glass. The results show that glass of high quality can be produced specifically for Ar—Rayis region which would be of interest to researchers, glass industry personnel and potential investors
{"title":"Prospects and State of the Glass Industry in Saudi Arabia and a preliminary assessment of the quality of Glass and Glass-Ceramics Fabrication","authors":"E. R. Mahmoud, A. Shaharoun, A. Aljabri, H. Almohamadi, M. Farhan","doi":"10.20961/mekanika.v21i2.64294","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.64294","url":null,"abstract":"Although the economic value of glass products and its importance to the Saudi National Economy is vast, not much information is available about the current state of the art of the industry. Likewise little information is available about the geography, potential sites for mining sand as well as the evaluation of sand quality. This paper attempts to bridge this gap by presenting a feasibility study of fabricating normal glass and glass ceramics from Saudi Arabia’s domestically available raw materials. It discusses the current status of glass industry in Saudi Arabia and the Middle East region. It also gives a brief explanation about the sand topography in Saudi Arabia. In order to determine the feasibility of fabricating glass using these raw materials, experimental data on the fabrication of normal glass and glass-ceramics from indigenously available raw materials was obtained and reported as part of the findings of this paper Firstly, normal transparent glass were able to be fabricated without any apparent large defects using sand collected from Ar-Rayis region in Saudi Arabia. Four nano-sized crystallization catalysts, namely VC, WC, TiC and Y2O3, were added to the constituents of the glass in 3 wt.%. For VC, the crystallization process was limited. The glass ceramics of WC consisted of multi-dimensional edges crystals which covered all the matrix. Gray crystalline whiskers were obtained by addition of TiC. The Y2O3- glass ceramics consisted of multi-directionally rosette crystals. Finally, the microhardness values of the added crystallization catalysts glass ceramics were obtained and found to be much higher compared to normal glass. The results show that glass of high quality can be produced specifically for Ar—Rayis region which would be of interest to researchers, glass industry personnel and potential investors","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131390076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.64292
F. Imaduddin, Palgunadi Sastra, W. W. Raharjo, P. Wullandari, Ridwan Ridwan
The most significant environmental problem was caused by plastic. One way to handle plastic waste was using biodegradable plastic because it faster decomposes naturally. Biodegradable plastic can be made from carrageenan by the hot press method. This method can make biodegradable plastic with large dimensions. However, the plastic quality depended on the holding time, temperature, and pressure selected during the hot pressing process. Therefore, this research is conducted to determine the effect of holding time and temperature in the hot press process on the tensile strength of biodegradable plastic made from carrageenan. The composition of the biodegradable plastic material used was 35% carrageenan, 35% polyvinyl alcohol (PVA), and 30% glycerol. In the manufacture of composites, the holding time was varied: 10, 20, 30, and 40 minutes, as well as the process temperature varied from 100, 110, 120, and 130 °C. The tensile strength of the composite was observed through tensile testing using a Universal Testing Machine. FTIR, XRD, and SEM tests were also conducted to sharpen the analysis. The addition of holding time led to an increase in the tensile strength of biodegradable plastics. The highest tensile strength was obtained at a holding time of 30 minutes with a value of 4.45 MPa. After 30 minutes, the tensile strength of the biodegradable composite decreased. Meanwhile, the addition of process temperature caused a decrease in the tensile strength of biodegradable plastics. The highest tensile strength was obtained at a process temperature of 100 °C with a value of 5.28 MPa.
{"title":"Effect of Holding Time and Temperature of Hot Pressing on Tensile Strength of Biodegradable Plastic Made of Carrageenan","authors":"F. Imaduddin, Palgunadi Sastra, W. W. Raharjo, P. Wullandari, Ridwan Ridwan","doi":"10.20961/mekanika.v21i2.64292","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.64292","url":null,"abstract":"The most significant environmental problem was caused by plastic. One way to handle plastic waste was using biodegradable plastic because it faster decomposes naturally. Biodegradable plastic can be made from carrageenan by the hot press method. This method can make biodegradable plastic with large dimensions. However, the plastic quality depended on the holding time, temperature, and pressure selected during the hot pressing process. Therefore, this research is conducted to determine the effect of holding time and temperature in the hot press process on the tensile strength of biodegradable plastic made from carrageenan. The composition of the biodegradable plastic material used was 35% carrageenan, 35% polyvinyl alcohol (PVA), and 30% glycerol. In the manufacture of composites, the holding time was varied: 10, 20, 30, and 40 minutes, as well as the process temperature varied from 100, 110, 120, and 130 °C. The tensile strength of the composite was observed through tensile testing using a Universal Testing Machine. FTIR, XRD, and SEM tests were also conducted to sharpen the analysis. The addition of holding time led to an increase in the tensile strength of biodegradable plastics. The highest tensile strength was obtained at a holding time of 30 minutes with a value of 4.45 MPa. After 30 minutes, the tensile strength of the biodegradable composite decreased. Meanwhile, the addition of process temperature caused a decrease in the tensile strength of biodegradable plastics. The highest tensile strength was obtained at a process temperature of 100 °C with a value of 5.28 MPa.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130306527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-03DOI: 10.20961/mekanika.v21i2.58951
R. A. Rachmanto, Martinus Darmawan Bagas Wijayanto, W. E. Juwana, P. Kataraki
Ignition timing is sparking from the spark plug based on the ignition angle during the compression stroke in the combustion chamber relative to the piston position and the crankshaft angular speed. Adjusting the ignition angle is one method to optimize the combustion process in the engine. An optimal combustion process can improve engine performance and reduce fuel consumption. This study investigates optimal data from ignition angle changes using a programmable CDI. The test was performed on a single-cylinder fourstroke Otto engine with standard ignition angle variations, +3°, +6°, and +9° before TDC. The test results show that torque and power have increased while brake-specific fuel consumption has decreased. Optimal data acquisition at ignition angle of +9° with peak torque value of 6.91 Nm and peak power value of 4.80 kW, while the lowest value of specific fuel consumption is 0.234 kg/kWh, and the highest value of thermal efficiency is 36 %. From this study, it was concluded that the ignition timing could affect the engine performance.
{"title":"Experimental Test of Ignition Timing with Programable CDI on Performance Single Cylinder Otto Engine","authors":"R. A. Rachmanto, Martinus Darmawan Bagas Wijayanto, W. E. Juwana, P. Kataraki","doi":"10.20961/mekanika.v21i2.58951","DOIUrl":"https://doi.org/10.20961/mekanika.v21i2.58951","url":null,"abstract":"Ignition timing is sparking from the spark plug based on the ignition angle during the compression stroke in the combustion chamber relative to the piston position and the crankshaft angular speed. Adjusting the ignition angle is one method to optimize the combustion process in the engine. An optimal combustion process can improve engine performance and reduce fuel consumption. This study investigates optimal data from ignition angle changes using a programmable CDI. The test was performed on a single-cylinder fourstroke Otto engine with standard ignition angle variations, +3°, +6°, and +9° before TDC. The test results show that torque and power have increased while brake-specific fuel consumption has decreased. Optimal data acquisition at ignition angle of +9° with peak torque value of 6.91 Nm and peak power value of 4.80 kW, while the lowest value of specific fuel consumption is 0.234 kg/kWh, and the highest value of thermal efficiency is 36 %. From this study, it was concluded that the ignition timing could affect the engine performance.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122659540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-04-14DOI: 10.20961/mekanika.v21i1.48619
Muhammad Iyas Abdul Alim
The purpose of this study was to determine the effect of the transformation of savonius turbine blades using the Cp-TSR curve. The transformation referred to here is the change in the angular of the blade so that the area of the cross section of the blade moving downwind changes, by doing so the negative torque of the turbine obtained from the air flow is reduced. The specimen has 3 variations, namely, without transformation or conventional turbine and transformation of 5 and 10 degrees. With the reduction in the cross sectional area of the turbine blades, the authors hypothesize that the turbine performance will increase, but the blade transformation movement causes a shift in the center of mass which gives rise to vibrations that can directly affect turbine performance, and it could be that the negative effect from these vibrations is much greater than the positive effect from reducing torque. Experiments were carried out using wind tunnels with load variations at 5, 6, and 7 m/s speed variations. The experimental results obtained show that conventional turbines have better performance than turbines with 5o and 10o blade transformations.
{"title":"Effect of Turbine Blades Transformation on Savonius Turbine Performance","authors":"Muhammad Iyas Abdul Alim","doi":"10.20961/mekanika.v21i1.48619","DOIUrl":"https://doi.org/10.20961/mekanika.v21i1.48619","url":null,"abstract":"The purpose of this study was to determine the effect of the transformation of savonius turbine blades using the Cp-TSR curve. The transformation referred to here is the change in the angular of the blade so that the area of the cross section of the blade moving downwind changes, by doing so the negative torque of the turbine obtained from the air flow is reduced. The specimen has 3 variations, namely, without transformation or conventional turbine and transformation of 5 and 10 degrees. With the reduction in the cross sectional area of the turbine blades, the authors hypothesize that the turbine performance will increase, but the blade transformation movement causes a shift in the center of mass which gives rise to vibrations that can directly affect turbine performance, and it could be that the negative effect from these vibrations is much greater than the positive effect from reducing torque. Experiments were carried out using wind tunnels with load variations at 5, 6, and 7 m/s speed variations. The experimental results obtained show that conventional turbines have better performance than turbines with 5o and 10o blade transformations.","PeriodicalId":356258,"journal":{"name":"Mekanika: Majalah Ilmiah Mekanika","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130658254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：