Hasil untuk "Mechanical engineering and machinery"

Hao Wu, Yan Zhang, Xinrui Lyu et al.

Understanding the influence of water adsorption on gas transport properties is critical for optimizing coalbed methane (CBM) extraction. This study investigates the influence of adsorbed water on methane diffusion and apparent permeability in three coals representing sub-bituminous, bituminous, and anthracite ranks. The samples were selected as geologically representative end-members from major coalbed methane basins in China. Adsorbed water was introduced via humidity equilibration at 97% relative humidity, simulating residual moisture conditions typical of partially dewatered reservoirs. Pressure decay experiments show that under dry conditions, apparent permeability exhibits a non-monotonic variation with coal rank, with the medium-rank coal displaying the highest value among the three tested samples. Upon exposure to adsorbed water, apparent permeability decreases by 39% to 70% across all ranks, with greater suppression observed in low-rank and high-rank coals compared to the medium-rank sample. This rank-dependent response is attributed to differences in pore structure and water distribution associated with coalification history. While the findings are based on single samples per rank and reflect a simplified moisture condition, they provide mechanistic insight into how coal maturity modulates the sensitivity of gas transport to adsorbed water, offering implications for permeability modeling during the dewatering phase of coalbed methane recovery.

Ruka Yulia, Husni Husin, Muhammad Zaki et al.

This study investigates the isolation and application of a Klason-lignin-based biosorbent derived from sugar palm fruit shell (SPFS) waste for the adsorption of Pb(II) and Cd(II) from toxic wastewater. The SPFS waste, rich in lignocellulose, underwent pretreatment to extract lignin-containing functional groups suitable for metal ion adsorption. The biosorbent's morphology before and after adsorption was analyzed. Adsorption effectiveness was evaluated through isotherm and kinetic models, with optimal conditions determined using Box-Behnken Design and Response Surface Methodology. Maximum adsorption capacities of 31.35 mg/g for Pb(II) and 12.5 mg/g for Cd(II) were achieved. Optimal conditions, based on Box-Behnken design, were 116.535 mins, 60 mg/L concentration, and 0.5 g adsorbent mass, resulting in adsorption efficiencies of 94.48 % and 60.98 % for Pb(II) and Cd(II), respectively. This research demonstrates the potential of Klason lignin from sugar palm fruit shell (KLSPFS) as an effective biosorbent for Pb(II) and Cd(II) removal, contributing to sustainable development goals 3, 6, and 12 by promoting efficient recycling technologies for improved health, water quality, and waste reduction.

Yu. A. Tsoy, V. V. Kirsanov, R. A. Mamedova et al.

The paper shows the development of technologies and tools of mechanization and automation in livestock farming for the period from 1930 to the present. (Research purpose) Given the cyclical nature of processes and the nuanced interpretations of scientific heritage, it is necessary to investigate the historical experience and contributions of scientists to the development and practical implementation of mechanization and automation tools in livestock farming. (Methods and materials) The paper examines the primary stages of mechanization and automation in cow milking, starting with the development of the first Soviet three-stroke milking machine DA-3. It considers the contributions made by specialized institutes of the All-Russian Academy of Agricultural Sciences and individual scientists in formulating testing methodologies for milking machines. Additionally, it explores the development and adoption of novel electromechanical tools for dairy farms. (Results and discussion) Considered in this paper are the pioneering efforts in the creation of the first milking parlors. These include the stationary herringbone type machines with a parallel-pass design, spearheaded by V.S. Krasnov, V.F. Korolev, V.P. Larin, V.P. Pokhvalensky, and A.N. Dormidontov, and the development of mobile carousel parlors of the «rotating herringbone» type, engineered by the design bureau of the Siberian Research Institute of Agriculture under the supervision of I.I. Teslenko, N.V. Krasnoshchekov, K.S. Shapovalov, N.K. Vazenmiller, A.V. Goldenfang. (Conclusions) The paper notes the significance of adopting a systematic approach to the developing of machinery for livestock farming mechanization. This approach was actively pursued by N.M. Morozov, the member of the Russian Academy of Sciences. A significant milestone in the advancement of the theory and practice of animal husbandry processes was the pioneering work in developing and implementing technology for flow-conveyor animal service, headed by Member of the Russian Academy of Sciences L.P. Kormanovsky. The paper reveals the necessity of conducting a historical practices from previous generations. This approach helps to develop modern models of machinery and equipment and avoid mere replication of foreign designs. It also facilitates independent research and development efforts, incorporating insights from the accumulated experience of utilizing equipment and technologies in Russia.

Ana Nurhasanah, W. Hermawan, T. Mandang et al.

Sorghum is a versatile plant with various parts that can be utilized. However, information on the physical and mechanical properties of the sorghum plant is crucial for designing agricultural machinery for primary handling processes such as threshing and chopping. This study aimed to determine the technical characteristics of sorghum plants (Bioguma variety) including the physical and mechanical properties of the stems, leaves, panicles and seeds to design a configuration system concept for threshing and chopping machines capable of processing sorghum plants with high moisture content immediately after harvesting. The study used a descriptive method and included samples of sorghum plants randomly taken from fields in Majalengka and Bogor, Indonesia. The physical and mechanical properties were measured using several replications, ranging from 3 to 30 depending on the parameter. The sorghum plants were harvested at at ages 80, 90 and 108 days after transplanting (DAT). It was found that the moisture content of sorghum stem and seeds decreased with the increase of plant ages where stem ranged between 84.18–79.81 %wb and seeds ranged between 51.7–29.4 %wb. The result revealed that planting ages influenced its properties including stem properties and seed properties. Longer DAT increased the stem hardness from 290.64 ± 29.41 to 350.00 ± 0.81 N and seed hardness from 8.2 ± 1.7 to 44.9 ± 5.4 N but decreased the tensile force of seed form panicles from 16.7 + 3.2 to 6.0 ± 0.8 N. The data on stem strength and seed hardness provide important considerations for the development of several equipment for sorghum processing. The findings of this study can serve as a basis for designing effective and efficient threshing and chopping machines for sorghum plants at high moisture content.

Thingujam Bidyalakshmi, Thongam Sunita, Shaghaf Kaukab et al.

Tamarind is widely consumed as fruit and spices in India. Tamarind contains  pulp, seeds, shell and fibres. The pulp, which makes up between 30 and 50% of the mature fruit, is rich in reducing sugars, pectin, protein, fiber, and cellulose substances. Study of various physical engineering properties such as moisture content, fruit size, length, width, thickness, and weight (pulp, seed, shell, etc.) is important for designing the post-harvest machineries of tamarind.  Major unit operations for processing of tamarind includes drying, dehulling, deseeding, pressing and storage. Traditional and mechanical approaches are used for these operations. Mechanical approaches of tamarind processing are carried out by dehuller and deseeder machinery. One of the crucial unit procedures in the processing of tamarind is deseeding which can be done by deseeder, mechanically. Processing of raw tamarind into value-added goods may increase its worth in addition to increase in shelf life. Additionally, it boosts the income of producers and processors. Value added products of tamarind are pulp, tamarind juice concentrate, tamarind pulp powder, tamarind pickle, tamarind jam, tamarind syrup, tamarind candy, tamarind kernel powder, dried fruit block, tamarind chutney and beverages. Tamarind is also rich in major amino acids phytochemicals and hence it carries the properties of antidiabetic, antibacterial, antivenomic, antioxidant. This paper provides an overview of the engineering properties, processing technologies, value added products, technologies and machineries developed/available for tamarind and its health benefits which will further help in machinery, protocol, technology and product design and development.

N. Dubrovina

The presented article considers the current economic situation, taking into account the restrictions of imported supplies of products, equipment and technologies. The need to develop domestic engineering in the field of high-tech equipment production, to create a powerful innovation and technological potential on the basis of enterprises producing modern machines and developing advanced technologies is justified. The trend in the development of mechanical engineering in one of the industrialized regions the Samara region was analyzed. It was revealed that the main supplier of machinery and equipment to the domestic market today is a domestic manufacturer, the production capacity of which in some sub-industries operates at the limit. In this regard, a significant increase in investments in the renewal of fixed assets is necessary. The increase in the production of innovative high-tech equipment is associated with significant investments and serious time costs, even if financing is carried out from the federal budget. The reason for the weak investment activity of enterprises is the low profitability of production and an unstable external environment. The priority should be the development and development of innovative equipment that meets the modern requirements of the innovative and technological development of industry.

Tom Vandebroek, Julie Legrand, Tom Vercauteren et al.

Single port access surgery has brought many advantages and new challenges to the field of minimally invasive surgery. In principle, many of these challenges can be addressed through robotics. Continuum robots in particular have seen a surge in interest in recent years for their miniaturisation potential. However, many applications with these robots have been developed for contactless or low-force tasks. This paper tackles several barriers to high-force tasks with continuum robots such as suturing for Open Spina Bifida repair. A novel continuum robot end-effector is proposed. The end-effector is composed of a distal bending segment and hybrid gripper. First, the novel hybrid gripper specifically designed for continuum robots is introduced. The hybrid gripper can function both as a general surgical gripper and as a needle driver while overall keeping the required input force limited. Second, an optimisation of the continuum structure of the distal bending segment is conducted. The objective of this optimisation is to sustain high tip forces – required by the said high-force contact tasks – while keeping deformations acceptable. Third, a quasi-static model that predicts the coupled effect of bending and gripping is derived. This model predicts the deformation of the continuum structure that is induced by the gripping action itself. It could hence be used to compensate for such deformation and establish a stable grip with the otherwise flexible instruments. Finally, experiments are conducted to validate the new designs and the model. The hybrid gripper has a diameter of 3 . 4  mm, a length of 15 . 5  mm and can hold securely a needle with a 4  N input force, outputting a 12  N gripping force. The optimised bending segment is validated for Open Spina Bifida suture: it can bend freely up to 90° and it can support a 1  N tip load up to a 35° bending angle. The bending and gripper model error varies between 1% and 14.55%, yielding useful results to predict the shape of the bending segment and potentially compensate for the disturbance created by actuating the gripper.

F. U. Zhuraev, Q. I. Ruzikulov, E. F. Urinov

The problem of increasing the irrigated lands productivity and ensuring sufficient reserves of minerals and nutrients for plants is noted to be important in the Republic of Uzbekistan. In practice, when preparing land for sowing cotton, wheat, soybeans and other crops, the application of mineral fertilizers is provided with the help of a chisel cultivator that has two separate hoppers for mineral fertilizers with a capacity of 50 kilograms each. It was revealed that large lumps of caked fertilizers remain in the hoppers, which reduces the productivity and quality of the unit. It was recommended to use an improved device with one container and special grinders for mineral fertilizers installed there.Research purpose To substantiate the parameters for the grinder of large lumps of mineral fertilizers in the chisel-cultivator hopper.Materials and methods The study was focused on the parameters and performance of a mineral fertilizer grinder operating by means of a rotation provided by the unit support wheel.Results and discussion The parameters of the chisel-cultivator were determined for grinding and applying mineral fertilizers at the stage of preparing the soil for sowing.Conclusions A unit with grinding working bodies was developed to install in a chisel-cultivator hopper. The following parameters were specified: the shaft diameter is 40 millimeters, the toothed bar height is 25-30 millimeters, the width is 8–10 millimeters, and the thickness is 2-3 millimeters. In total, 18 bars were fixed in one compartment of the hopper, and 180 pieces in 10 compartments. The selected parameters of the mineral fertilizer grinder in the hopper with a capacity of 350 kilograms facilitate the application of up to 300 kilograms per hectare.

Q. Mi, S. H. Yi, X. H. Zhao et al.

The cooling effectiveness of optical window influences the imaging quality of hypersonic vehicles. This study focuses on the supersonic film cooling efficiency on the optical window of a blunt cone in hypersonic flow. The experiments were conducted in a gun tunnel equipped with a Mach 8 nozzle providing a total pressure and temperature of 9 MPa and 900 K respectively. Three tangential 2D nozzles with different combinations of slot heights and Mach numbers were designed to detect the film cooling length under different injection pressures. The heat flux on window surface was measured by Thin Film Gauges and the flow field was monitored by schlieren technique. When the jet pressure matched the mainstream, the window was completely cooled, and the minimum mass flow rate was achieved when the slot height was 5mm and the jet Mach number was 2.5. If the pressure ratio of jet continues to increase, the heat flux density could be furtherly reduced, but the cooling efficiency of unit coolant mass flow decreased significantly. The data correlation results showed that the cooling efficiency presented a nonlinear relationship of second order polynomial with (x/Sh)λ-0.8 , and the effective cooling length of film was positively correlated with the cooling mass flow ratio (λ) and slot height of the nozzle. Besides, the increase of jet pressure resulted in thickening the mixing layer, which enhanced the heat insulation effect and reduced the heat flux as a result.

Yanmin Wu, Jinli Qi

The rapid development of the information age brings convenience to human life, but it also brings great challenges to information processing technology. Multimedia enhancement technology is an organic combination of multimedia technology and information processing technology, and it is also an important way of modern multimedia image information processing. However, its usefulness and effectiveness are increasingly negatively affected by the open information environment. The processing effect is also unable to meet the development requirements of the visual field. In order to improve this problem, this paper studied the image transmission and processing system of network-controlled robot on the basis of analyzing the characteristics of the problems existing in the current stage of multimedia technology. On this basis, a new image processing variational model was established and applied to multimedia enhancement technology, which improved the efficiency and effect of image information processing. Finally, the feasibility of its application function and performance was tested by experiments. The test results showed that in the difficult mode of the image processing task, the refresh time of the model in this paper in the multimedia enhancement technology was 1.13 s in total, which was not much different from the test results in the easy mode. Also, in the load stress test, the comprehensive test values under full-function operation and partial-function operation were 42.04% and 20.92%, respectively. Compared with the traditional model, the model in this paper has stronger carrying capacity in multimedia enhancement technology and has better processing ability and stability.

R. S, A. Mishra

This paper provides an overview of the increasing R&D activity in metal matrix composites worldwide, with a particular focus on cast particulate metal matrix composites. Large-scale applications of cast aluminum alloy MMCs in everyday use in the transportation and consumer durables industries are expected to advance rapidly over the next decade. India has great potential for widespread application of cast composites, especially in the fields of transportation, energy and electrical machinery. Widespread use of composites can result in significant material and energy savings and, in some cases, reduced pollution. It is important to organize engineering education and short courses to make students and engineering professionals aware of his MMC. India already has an excellent infrastructure for composites development and a long track record of world-class cast metal matrix composites research. Today there is a need to catalyze prototypes and series production of selected composite components and use them in various sectors, especially in railways, cars, trucks, buses, scooters and other electrical machines. This requires a well-funded strategy to bring together the world-class foundry composites talent already present in India to form a viable development group. We will then establish a manufacturing facility that incorporates the process engineering capabilities that already exist in the country. Cast composites must be developed for use in power generation equipment, aerospace electronic packaging systems, and smart structures.

P. Dorodov, V. Kasatkin, N. Kasatkina et al.

Today, new methods of manufacturing complex parts using three-dimensional printing are being introduced in engineering, including in the mechanical engineering of agricultural machinery. This technique is also used in the design of agricultural machinery at the stage of physical modeling of their structures to determine certain properties of the product as a whole and its individual parts (details) on the corresponding models. Physical modeling is used when it is difficult to perform full-scale tests of the product, as well as for economic reasons. The necessary conditions for physical modeling are the geometric and physical similarity of the model and kind. The presence of such proportionality allows us to recalculate the experimental results obtained for the model in kind by multiplying each of the determined values by a constant multiplier for all values of this dimension – the similarity coefficient. However, to study the physical characteristics of a product, it is necessary to take into account the mechanical properties of the material of its model. From various sources, you can find the main mechanical characteristics of plastic threads or samples made on a 3-D printer. Their values vary greatly depending on the model manufacturing technology. The paper presents the results of a study of the physical and mechanical properties of polylactide (PLA) and polyethylene tereflatate (PET-G), which are used in the manufacture of parts by three-dimensional printing. The specific strength of polymers was respectively: for PLA 65.6…12.2 kPa·m3/kg, for PET-G 36.7…95.4 kPa·m3/kg. Specific plasticity for PLA is equal to 60.,3 %· cm3/kg, for PET-G – 468.2 %· cm3/kg. The specific plasticity for PLA is 608.3 %· cm3/kg, for PET-G – 468.2 %· cm3/kg. Mechanical properties are investigated and the obtained mechanical characteristics must be taken into account when calculating and physically modeling plastic products for three-dimensional printing.

Vaishally Dogra

In a variety of engineering disciplines, including the mechanical, aerospace, and energy industries, the study of nonlinear dynamics and vibration analysis of rotating machinery has become increasingly important. In many applications, including turbines, engines, compressors, and pumps, rotating machinery is essential for both the performance and safety of the entire system. Nonlinearities, on the other hand, add intricate dynamic behaviours and vibration phenomena into these systems, which can result in subpar performance, excessive wear, and even catastrophic failures.The goal of this research is to improve rotating machinery's design, operation, and maintenance by examining the nonlinear dynamics and vibration properties.In order to comprehend the complex interplay between the dynamics of the rotor, the dynamics of the bearing, and the nonlinear forces, the analysis makes use of sophisticated mathematical models and computer tools. To appropriately depict the system's nonlinear behaviour, important factors including rotor imbalance, shaft misalignment, bearing clearance, and non-circular journal shapes are taken into account.The objective of the project is to create reliable techniques for locating and forecasting important vibration modes, resonances, and instabilities in rotating machinery. Techniques like nonlinear time series analysis, bifurcation analysis, and chaos theory are used in this. The results of this study can help in the creation of efficient vibration mitigation plans and condition monitoring tools as well as useful insights into the underlying physics of rotating machinery dynamics. This paper findings may help to increase the performance, reliability, and lifetime of rotating machinery, which would increase operational effectiveness and lower maintenance costs across a range of industrial sectors.

Hongbo Chen, Y. Huo, Yudong Xu

It is critical in intelligent manufacturing that monitors devices to sustain normal status. Recently, the artificial intelligence‐powered diagnosis is the key in smart monitoring process and has become a hot topic in the engineering field. In previous diagnostic methods, complete failure samples are the premise to activate the intelligent diagnostic model. However, the actual failures of the mechanical diagnostic are far more than that we can obtain under running state in advance. In order solve this issue, this paper adopts Generative Adversarial Networks (GAN) by using simulated data to obtain complete failure samples, which builds a bridge between artificial intelligent model and mechanical fault diagnostic system. In mechanical diagnostic system, we first use finite element simulation to generate the missing fault samples. The generated and existing fault samples are supplemented each other to construct complete failure samples. The complete failure samples are used as training set to train an intelligent model which is used to predict the status for future status of mechanical system. The status of mechanical system is represented as the signal from distributed sensors. The fault diagnostic system is verified on a public mechanical system dataset and the results demonstrate it is superior to previous ones.

Chunyang Wang, Fumin Zhu

As far as China's current economic development is concerned, economic development depends heavily on machinery manufacturing. Machinery manufacturing has provided great help for China's economic development, but the traditional machinery design and manufacturing can no longer meet the requirements of social development in the new era. For traditional mechanical design and manufacture, there has also been a historic change. The impact of new technical methods on traditional mechanical design and manufacture has also promoted the development of mechanical design and manufacture towards automation, which has become a mainstream trend of mechanical design and manufacture at present. In this paper, the theme of mechanical design and manufacture and its automation application based on multi-agent is discussed. Firstly, the background of this paper is briefly introduced, and then the advantages of mechanical design and manufacture and its automation application are analyzed. Then, the application of automation technology in mechanical manufacturing process is analyzed from different aspects, and the future development is prospected.

Mao Yang, Bozhi Dai, Jinxin Wang et al.

Abstract To satisfy the grid operation scheduling requirements for wind power forecasting model accuracy, the measured wind speed near the height of the wind turbine hub is added to the wind power combined forecasting model. First, the relationship between the numerical weather prediction wind speed and the measured wind speed at different heights are analysed, and the correlation between each wind speed and the wind power is compared. Second, the random forest algorithm combined with the cumulative contribution rate is used to select several meteorological types of numerical weather prediction data as the input of the long short‐term memory network to predict wind speed. Third, while inputting the meteorological data provided by numerical weather prediction, which is highly related to wind power, the wind power prediction network also uses the predicted wind speed of the upper network as input to predict wind power. Finally, the entropy method is used to dynamically determine the combined weights of each forecasting model and improve the adaptability of the model. Research and analysis using measured data from two wind farms located in northeast China have verified the effectiveness of the method.

Shaofei Shen, Xin Wang, Yanbing Niu

Inertial microfluidics enables fluid and particle manipulation for biomedical and clinical applications. Herein, we developed a simple semicircular microchannel with an ultra-low aspect ratio to interrogate the unique formations of the helical vortex and Dean vortex by introducing order micro-obstacles. The purposeful and powerful regulation of dimensional confinement in the microchannel achieved significantly improved fluid mixing effects and fluid and particle manipulation in a high-throughput, highly efficient and easy-to-use way. Together, the results offer insights into the geometry-induced multi-vortex mechanism, which may contribute to simple, passive, continuous operations for biochemical and clinical applications, such as the detection and isolation of circulating tumor cells for cancer diagnostics.

Z. Murčinková, S. Radchenko, G. Kuchtová

The structured composite can involve the porous materials providing the important internal damping that is usable in mechanical engineering applications. The stiff base material is equipped by layer/s of softer porous material/s covered by constrained layer. Such layered structure is characterized by increased internal damping in vibration process. Paper analyses some either measured or simulated mechanical properties of designed layered porous composites. Novelty provided in paper is a specific application of structured composite for damping the high frequency vibrations in resonance frequency obtaining the beneficial results, e.g. 40-48% of maximum amplitude reduction.

E. Shakhmatov

The article analyses vibration protection solutions based on the development and wide usage of porous elastic damping isolators and applied for mechanical systems and aerospace engineering products. The paper includes case studies of the implementation of developed vibration protection methods and means. They are grounded on the general properties of structural damping systems, methods for modelling dynamic processes in products and approaches to controlling the structural dynamics under the vibration loading.

Jianguo Gu, Yimin Zhang

In engineering applications, angular contact ball bearings are usually mounted in pairs to accommodate the high-speed and heavy-load conditions. The usability, security, and stability of rotating machinery systems are heavily dependent on the mechanical behaviors of matched angular contact ball bearings. However, few related works about matched bearings have been reported. Consequently, it is of great significance to investigate the mechanical properties of matched bearings. This paper presents an analysis of the stiffness and fatigue life characteristics of matched angular contact ball bearings under axial position preload. First, an improved quasi-static model is proposed by using universal coordinate transformation method to investigate the stiffness characteristics of matched bearings. On basis of this, the fatigue life of matched bearings under running condition can be calculated. Then, the validity of the proposed model is verified via comparison between calculated results with previously published experimental results. Finally, a pair of 7206B bearings is taken as a numerical example to illustrate the application of the proposed model. The effects of bearing configuration form, preload, external loads, rotating speed on the stiffness, and fatigue life of matched bearings are discussed in detail.