Applied Mechanics and Materials Vol. 914

Abstract: Currently, the research on the application of Single point incremental forming technology (SPIF) in Vietnam is limited. Therefore, the study of technology and equipment for the fabrication of SPIF machine and research on the ability of deformation of the formed material sheet is necessary and should be urgently carried out. The paper proposes a new approach to modularizing the structure of the Single point incremental forming machine by using standard parts, thereby improving the quality and reducing the cost of the machine and improving accuracy of the machine.

Abstract: The plastic manufacturing industry, like many other manufacturing industries, is going through great and rapid changes since the 4th industrial revolution. In addition to more conventional innovations such as factory automation, this industry has started to experience more advanced technologies like Internet of Things, augmented reality,... This article presents a case study on the applicability of automation and several technologies from the 4th industrial revolution to the plastic manufacturing industry. To be more specific, the article will demonstrate the process of building a semi-automated flush valve testing system to replace the manual testing process and integrating monitoring, data acquisition, and augmented reality technologies into the above system. The results compared with the manual testing process at a sanitary accessory manufacturing in Vietnam show that the application of those technologies is possible and can solve many issues commonly found in the manual testing process.

Abstract: Monosodium Glutamate (MSG) [1] was invented more than 100 years ago from its first invention in 1908 by Japanese biochemist Kikunae Ikeda, who was trying to isolate and duplicate the savory taste of kombu, an edible seaweed used as a base for many Japanese soups. From 2016, most MSG worldwide is produced by bacterial fermentation in a process similar to making vinegar or yogurt. Sodium is added later, for neutralization. During fermentation, Corynebacterium species, cultured with ammonia and carbohydrates from sugar beets, sugarcane, tapioca (cassava tuber) or molasses, excrete amino acids into a culture broth from which L-glutamate is isolated. In this process, Monosodium Glutamate companies buy cassava [2] pulps from farmers that contain a lot of sand and impurities. In order to increase the productivity with lowest expense, the filtration of sand and solid impurities’ is performed by separation cyclone. In this paper, we study all the measure to design a system of effective pump, cyclone to extract as much as possible all of solid impurities included sand out of cassava slurry before providing to the bacterial fermentation in a process.

Abstract: In this work, a non-evaporative cooling system is used with an assisted thermoelectric cooler (TEC) devices module. The system was proposed as an alternative cooling system in the high temperature climate to overcome the high energy consumption of traditional air-conditioning compression cycle. The open source Open FOAM V.9 was used to solve the transient effect of 3D model of indirect non-evaporative cooling system. The primary air temperature was set to 319 . While, the air flow was tested under four different air inlet velocities: 0.75 m/s, 1 m/s, 1.25 m/s, and 1.5 m/s. the validation shows good and acceptable agreement in COP values of the system with both experimental and theoretical works from literature within an error between (12.9 % and 9.5 %). Results show that the temperate difference value on a slice through the length of the air channel starts to decrease as velocity increasing. For example, at the last timesteps of each velocity, the temperature difference reaches about (~10 ^oK) when velocity is (0.75 m/s) starting from the first quarter of the channel, while the same difference in temperature not reached until the half way of the channel from the channel inlet when velocity is (1.5 m/s). Revealing that even though the percentage increase in the velocity is about 50%, the change in the temperature difference value between the inlet and outlet of the channel is about 1.2%. The local Nusselt number shows that steady state heat transfer reached very quickly as the velocity increased (i.e., at 0.75 m/s at 12s while for 1.5 m/s at 4s). Notwithstanding, as the time processed the ( increases for all cases but becomes lower as the velocity increased. .

Abstract: Meeting stringent emission regulations, the demand for environmentally friendly fuels is increasing by the day. Alternative fuel must be burned alongside conventional fuel to increase the availability of such clean energy sources. The current experimental study investigates the characteristics of the premixed LPG flames with CO₂ dilution in tube swirling and non-swirling burners. The study including testing the effects of equivalence ratios, φ, (0.8, 1, 1.2, & 1.4), CO₂ dilution ratios (0%, 5%, 7.5%, & 10%), and aspect ratio of the non-swirling burner (2, 4, 6, 8, & 10). Two swirling burners with swirl number was tested, namely 0.78 & 0.48. The dilution of CO₂ has been observed lengthens the flame, particularly at higher equivalence ratios and/or flow rates since there is more than one influence, they all agree on a similar influence on flame height. The flame shortens clearly when using a swirling burner. Besides, when increasing the swirl number, the flame height increases slightly. Also, the swirling burner divided the flame's inner core into segments equal to the number of swirl vanes, and a flower-shaped flame was generated at low flow rates. The burner’s aspect ratio affects flame height insignificantly. Flame stability limits increase for a higher equivalence ratio and it enhances due to CO₂ addition. The LPG-CO₂/air mixture has an improved reply to beat flame flashback. The addition of CO₂ expands the flow rate of stable flame by about 40% and 25% for φ = 1 and 1.2 respectively. Utilizing a swirling burner improves flame stability greatly. The limit between flashback and blowout increased by about three times as a result of using a swirling burner.

Abstract: The purpose of this research is to better understand the characteristics of two-phase flow in a rectangular bubble column. Computational Fluid Dynamics (CFD) (ANSYS-FLUENT R15.0®) has been used to conduct numerical studies of the flow pattern. Furthermore, the experimental data is used to verify the accuracy of the numerical data. This unique CFD simulation research included a 3D system, Reynolds-Average, Navier-Stokes equations (RANS), k-turbulence model, and total interphase forces. Bulk flow patterns were revealed through CFD analysis. Total contact force, both constant and non-steady, is also analyzed for its impact. The data show liquid upflow in the column's bulk section and liquid downflow near the wall. In the gas phase, bubbles rose in the middle area and departed the bed. In addition, bubbles without enough velocity to leave the bed circulate towards the wall with liquid and follow a similar pattern. The results show that the phenomenon of the central peak can only be captured by using a single bubble and no drag forces. The correlation between simulation and experimental findings is excellent. Within the higher, middle, and nearby gas distributor height ranges, the outcome agrees extremely well with the experiment. In addition, the results of the experiments show that the level of turbulence has played a crucial role in dynamic behavior. The CFD model described qualitative and quantitative flow performance, producing excellent results. The results also gave a framework for comparing and evaluating future designs and gave insights into the fluid dynamics of the bubble column reactor. Efforts were made to compare and contrast the main operating modes of different reactor designs. Keywords: Two phase, Ansys, Bubble column, CFD, Drag force, Flow Pattern.

Abstract: This paper presents the simulation of beef freezing process by using ANSYS software. On the basis of simulation results, factors affecting the freezing time including air velocity and freezing temperature were determined. Within the air velocity range ω = (5÷15) m.s^-1, an increase in the velocity by ω=1 m.s^-1 led to a decrease in the freezing time by τ =(6,5÷2,0) %. When the freezing temperature was reduced by t_e = 1 K, the freezing time was reduced by τ = (3,2÷2,5) % in the freezing temperature range t_e = (–35÷–45) °C.

Abstract: Cellulose is one of the main components of plants, depending on the plants, the cellulose content can be up to 98%. Cellulose has a wide range of use. It can be used in the food industries, pharmacy, paper, and chemical industries. To extract the cellulose from biomass, the biomass needs to undergo a pre-treatment. This study uses steam explosion pre-treatment as it does not cause hazards to the environment, has low energy cost, and low investment cost. In this pre-treatment, steam will be injected into the biomass until the pressure reach 15 bar, then decline rapidly to make an explosion that causes damage to cellulose crystalline. After that, the process continues to main process, which are washing, and alcohol extraction. Then continued to alcohol recovery. After considering many factors, a cellulose plant from rice straw will be built in 2023 in industrial parks Java Integrated Industrial and Ports Estate or known as JIIPE with a capacity of 370,000 tons/ year. Based on economic analysis, this plant has an internal rate of return of 35.17% and a payout time of 3.98 years. This makes this plant feasible to be built.

Abstract: Oil palm processing produces more than 70-wt% of its lignocellulosic content as by-product, the bulk of which is empty fruit bunches (EFB). EFB contains cellulose, hemicellulose, and lignin which makes it a potential source of bio-based chemicals. This research explores the utilization of ethanol as a potentially green, sustainable, and low-cost organic solvent (organosolv) for EFB fractionation. Organosolv processes target extraction of lignin (delignification). Conventional delignification use an acid hydrolysis process with lignin yields of approximately 18-wt%. In this study the EFB was treated in 2 stages, (1) soaking EFB for 1 hour followed by (2) delignification using ethanol as the organic solvent under variable process conditions. Temperature (140°C, 170°C), liquid-to-solid ratio (L/S-w/w) (6:1, 15:1), and wt%-ethanol (20-wt%, 50-wt%) were varied while residence time was constant at 30 minutes (experiments were run in duplicate). Data analysis using 2k Factorial Design Method showed the significant variables were temperature, L/S-ratio, wt%-ethanol, interaction of L/S ratio and temperature, temperature and %wt-ethanol interaction, and L/S-ratio and %wt-ethanol. The optimum operating conditions (170°C, 15:1, 20wt%-ethanol) produced a lignin yield of up to 31%wt. This preliminary study shows ethanol in an organosolv process is a potential delignification option.