Parameter Optimization Analysis Research Articles

Structure Parametric Optimization and Mechanical Analysis of the MSe1 Septum Magnet

Structure Parametric Optimization and Mechanical Analysis of the MSe1 Septum Magnet

Analysis of Film Unloading Mechanism and Parameter Optimization of Air Suction-Type Cotton Plough Residual Film Recovery Machine Based on CFD—DEM Coupling

Analysis of Film Unloading Mechanism and Parameter Optimization of Air Suction-Type Cotton Plough Residual Film Recovery Machine Based on CFD—DEM Coupling

Mechanical and Sliding Wear Performance of Vacuum-Cast AA7075-Co Alloy Composites: Parametric Optimization and Ranking Analysis

Mechanical and Sliding Wear Performance of Vacuum-Cast AA7075-Co Alloy Composites: Parametric Optimization and Ranking Analysis

Parametric design optimization and thermodynamic analysis of plate fin heat exchanger for helium liquefaction system

The plate-fin heat exchanger is one of the most important components of helium liquefaction system as it recovers cold energy from helium gas in the cold box. Because of larger heat transfer surface area and compact geometrical configuration, plate-fin heat exchangers are widely used. The design of heat exchanger using helium as a cryogenic fluid needs high thermodynamic performance with minimum pressure drop which particularly requires the optimization of dimensional array and its geometrical configurations. In this regard, a parametric investigation was performed to compute the effective geometrical parameters and its effect on thermodynamic (effectiveness and log-mean temperature difference) performance has been discussed in detail. The present study aims to design optimization and thermodynamic performance evaluation of plate-fin type heat exchangers used in helium liquefaction systems. The developed helium liquefaction model has been simulated for the most critical liquefier with and without liquid nitrogen precooling, mixed mode, and refrigeration mode. Each component of the liquefaction model has been technically and thermodynamically analyzed and, in particular, four plate-fin heat exchangers have been considered and designed accurately using Aspen EDR®. Initially, the sensitivity analysis was carried out to characterize the most significant geometrical parameters (fin thickness, height, number and arrangement of layers, frequency, and fin type) and their effect on thermodynamic performance and pressure drop. After that, the artificial intelligence model was used to determine the optimal range of such geometrical variables in which the heat exchanger has maximum effectiveness and log mean temperature difference. Finally, the operating conditions obtained from cycle modeling and optimized geometrical datasets have been applied in commercial simulation software Aspen EDR® for plate-fin heat exchangers design. Finally, a comparative thermodynamic analysis has been carried out to determine the performance of all the designed heat exchangers operating at four different modes (boundary conditions).

The Design and Process Parameters for the Optimization of an Ultrasonic—Thermal Co-Sterilization System for Liquid Eggs

The sterilization of liquid eggs plays a crucial role in the production of liquid egg products. Traditional pasteurization techniques can easily cause protein denaturation, while non-thermal sterilization techniques are often constrained by processing intensity and time. Improving the effectiveness of liquid egg sterilization while preserving the stability of its functional attributes poses a significant challenge. In response to this issue, a synergistic ultrasonic mild thermal sterilization system for liquid eggs is proposed, accompanied by the optimization of its process parameters. COMSOL is employed to simulate the acoustic field distribution of the ultrasonic–thermal system in the liquid egg medium. Verification is conducted through acoustic intensity measurements, and analysis is performed to obtain the optimal arrangement of ultrasonic transducers. Based on Modbus communication, an ultrasonic–thermal synergistic sterilization system is designed. Sterilization experiments are conducted with both 20 kHz + 28 kHz and 20 kHz + 40 kHz multifrequency ultrasound, compared with traditional 20 kHz single-frequency ultrasound. The results indicate that multifrequency ultrasound improves sterilization efficiency by approximately 15% compared to traditional single-source ultrasound. Utilizing multifrequency ultrasonic–thermal synergistic sterilization experiments, a three-factor, three-level response surface test is conducted with sterilization rate and foaming properties as evaluation criteria. The results indicate a strong correlation between ultrasonic frequency, processing time, heating temperature, and sterilization performance, with the impact magnitude being sterilization temperature > processing time > ultrasound frequency. Parameter optimization analysis is performed using a genetic algorithm, yielding sterilization conditions of 55 °C, 11 min and 30 s processing time, and 20 + 40 kHz ultrasonic frequency. The liquid egg sterilization rate is 99.32%, an average decimal reduction of 3.17 log values, and foaming properties are 42.79%.Through comparative analysis, it is determined that the sterilization rate of the ultrasonic–thermal synergistic sterilization system meets national standards, and functional properties such as foaming are superior to traditional pasteurization. This validates the proposed ultrasonic–thermal synergistic liquid egg sterilization control system as effective and feasible.

Seismic control performance of multi-story structures with an enhanced particle inerter device (EPID)

An enhanced particle inerter device (EPID) is innovatively developed to mitigate the dynamic responses of multi-story structures subjected to seismic excitations. The device dissipates energy through tuning, particle-cavity collisions, and the inertia amplification effect of the inerter. Multi-story response can be mitigated when the inerter unit connect the particle device and the cross-story. In this paper, a shaking table test was conducted to investigate the working mechanism of the EPID on the dynamic response of multi-story structures. A series of parametric studies were undertaken to analyze both the individual and combined effects of the particle damping unit and inerter unit within the device. Furthermore, a parameter optimization analysis guided by a genetic algorithm was carried out, resulting in a significant enhancement of 27.92% in displacement control and 24.41% in acceleration control when compared to the traditional design. Moreover, the energy dissipated by the main structure with the optimized EPID shows a decrease of 45.4% when compared to the traditional design.

Reliability-based thermal-fluid-structural topological optimization of three-dimensional coolant channels in proton exchange membrane fuel cells

In order to minimize the flow resistance in designing the cooling multi-channels of proton exchange membrane fuel cells (PEMFCs) under the double constraints of target thermal reliability index and target structural performance, this work proposes a three-dimensional (3D) thermal-fluid-structural reliability-based topology optimization (RBTO) method for the first time. In the RBTO for PEMFCs’ coolant channels, the position uncertainty of the multi-heat loads on the bipolar plates caused by irregular metal foam skeleton is considered, and the multi-heat load positions are treated as the interval uncertain variables within a certain range. To solve the problem of low computational efficiency caused by the coupling of topological parameter optimization and reliability constraint analysis, the RBTO is equivalently decoupled to a sequence of cycles of deterministic topology optimization (DTO) and inverse reliability assessment, and the latter is completed by performance measure approach (PMA) based on the target reliability index. Results show that RBTO introduces more flow resistance cost than DTO, and the additional flow resistance in RBTO increases with the increase of the target reliability index. The heat concentration caused by a smaller fiber diameter of foam skeletons results in more flow resistance cost of RBTO compared to DTO. When the inlet velocity of the coolant channel varies in the region of 0.05–0.3 m/s, the flow resistance of the multi-channel obtained by RBTO is 1.29–0.96 times as that of the straight multi-channel. In addition, the uneven reactant gas concentration in PEMFC gas channels leads to the uneven distribution of heat flow, and it affects the temperature distribution on bipolar plates, which in turn affects the results of RBTO. The above method and findings can be applied to design the cooling channels of PEMFCs with irregular metal foam gas channels.

Significant duration prediction of seismic ground motions using machine learning algorithms.

This study aims to predict the significant duration (D5-75, D5-95) of seismic motion by employing machine learning algorithms. Based on three parameters (moment magnitude, fault distance, and average shear wave velocity), two additional parameters(fault top depth and epicenter mechanism parameters) were introduced in this study. The XGBoost algorithm is utilized for characteristic parameter optimization analysis to obtain the optimal combination of four parameters. We compare the prediction results of four machine learning algorithms (random forest, XGBoost, BP neural network, and SVM) and develop a new method of significant duration prediction by constructing two fusion models (stacking and weighted averaging). The fusion model demonstrates an improvement in prediction accuracy and generalization ability of the significant duration when compared to single algorithm models based on evaluation indicators and residual values. The accuracy and rationality of the fusion model are validated through comparison with existing research.

Tridiagonal Interval Matrix: Exploring New Perspectives and Application

Tridiagonal interval matrices are relevant in diverse applications, especially in dealing with parameter estimation, optimization and circuit analysis uncertainties. This research paper aims to improve the computational efficiency of obtaining the inverse of a general tridiagonal interval matrix. This matrix is pivotal in electric circuit analysis. We achieve this by employing interval arithmetic operations in the LU decomposition process, enabling effective handling of circuit parameter uncertainties. This approach generates an inverse interval matrix that addresses uncertainties in circuit analyses.

Design and test of tangential and longitudinal-axial threshing and separating unit for wheat

To achieve low loss and efficient wheat harvest in the Huanghuaihai region of China, this paper designed a tangential and longitudinal-axial threshing and separating unit (TLTSU). Key components such as the tangential threshing rotor (TTR), longitudinal-axial threshing rotor (LTR), and tangential concave were designed. Dynamic balance simulation of the threshing rotors was done to obtain the reaction forces at supporting ends of the threshing rotors and the amount of unbalance, and the amount of unbalance of the LTR was corrected to meet the standard requirement. Response surface optimization experiments of wheat threshing were conducted using throughput, TTR speed, and LTR speed as influencing factors and entrainment loss rate and impurity rate as test indicators. The regression models for the threshing device's entrainment loss rate and impurity rates were established. Through multi-objective parameter optimization analysis, the optimal threshing parameter combination for TLTSU was determined to be throughput of 8 kg s−1, TTR speed of 557 r·min−1, and LTR speed of 900 r·min−1. A validation experiment was conducted on this parameter combination, and the results showed that the entrainment loss rate was 0.27 % and the impurity rate was 28.23 %. The relative errors between the evaluation indicators and the predicted values of their regression models were 3.85 % and 1.4 %, respectively, which were less than 5 %, which proved the correctness of the regression model and provided a reference for the design of threshing and separating unit of wheat combine harvester.

Design, Installation, and Performance Monitoring of a 105 kWp Rooftop Solar PV System

Rooftop Solar PV systems are gaining growing attention on the path toward carbon neutrality. Hence, a great effort must be exerted to ensure smooth and efficient penetration of such systems into the existing utility grids. In the current work, a 105 kWp rooftop solar system is designed and installed to fulfil part of the electric demand of the faculty of Engineering, Zagazig University, Egypt. The performance parameters of this grid-connected solar PV system are optimized for the least-cost of electricity supply through using industry-standard software NREL SAM. For the current rooftop system, fixed orientation of an optimized tilt angle of 23 degrees is preferred over sun-tracking systems due to the reduced operating and maintenance costs. The annual energy production of the system is 175,700 kWh with a capacity factor of 19.1%. Through using parametric optimization and inter-connected financial analysis algorithms, it was possible to define the least cost for the electricity supplied to the grid to be 0.55 EGP/kWh, which achieves grid parity in Egypt. The project is finically profitable without any subsidy, with a discounted payback period of 7.9 years, and IRR (on equity) of 20.1 % and saves 1882-ton CO2 over its lifetime. Sensitivity analysis showed that the electricity escalation rate greatly enhances the project finances. In the first year of operation, the system performed fairly well compared with the theoretical design, provided that the system is frequently cleaned (at least once a week) and continuously connected.

Parametric topology optimization design and analysis of additively manufactured joints in spatial grid structures

This paper presents a complete computer-aided workflow for the parametric topology optimization (TO) design, numerical analysis and additive manufacturing (AM) of steel joints in spatial grid structures. A fully parametric TO design framework for steel joints in spatial grid structure was developed based on the Grasshopper platform. The joint models were parametrically established based on subdivision surface technology and further topology optimized through the bi-directional evolutionary structural optimization (BESO) algorithm with the support of cloud computing server. The structural performance of the optimized joints was thoroughly investigated via the parametric finite element analysis. Variables of loading conditions and TO parameters (target volume and filter radius) that affect the compliance, maximum displacement, maximum stress and stress distribution were taken into account. Analysis showed that the target volume governed the joint structural behaviour while the filter radius affected the geometric details of optimized joint. The practicability of proposed workflow was demonstrated through a parametric optimization design framework of a double-layer spatial grid structure with hundreds of steel joints. A typical optimized joint made of 316L stainless steel was additively manufactured using selective laser melting. This workflow is highly automatic and featured by high design flexibility and integration degree as well as good transplanted ability.

Theoretical analysis and model manufacturing of innovative mortise and tenon hollow spherical joint

One of the main challenges for free-form surface reticulated shell structure recently is the development of a new joint that is able to implement complex-shaped curvature and fulfill the required loading capacity, whilst also meeting various important requirements such as convenient on-site assembly and suitability for connecting members with various cross-sectional forms. This article draws inspiration from the construction idea of Chinese traditional mortise and tenon structure and proposes a new type of mortise and tenon hollow spherical joint. To investigate the joint’s mechanical performance, the detailed numerical models of 29 mortise and tenon hollow spherical joints with different size parameters are established by SolidWorks and Ansys, and the effects of the hollow spherical wall thickness, tooth width, tooth spacing, tooth height and tenon face width on the joint bearing performance are analyzed. The joint failure modes under bending limit states are discussed, and the calculation formulas for the initial and elastic-plastic stage rotational stiffness are derived. The results show that the joint initial rotational stiffness is increased by 34.45%, 4.69%, 4.29%, and 3.25%, respectively, after the parameter optimization analysis of the hollow spherical wall thickness, tooth width, tooth spacing and tenon face width. The mortise and tenon hollow spherical joint has good mechanical performance, and possesses the advantages of simple and beautiful appearance, fast construction speed and high positioning accuracy. Finally, a reduced-scale model of the mortise and tenon hollow spherical joint is manufactured using 3D printing technology to visually showcase its external feature and validate its assembly characteristic.

Double pulse gas metal arc welding process parameter optimization and weld performance analysis based on response surface method

Double pulse gas metal arc welding (DP-GMAW) is a low-frequency modulated high-frequency pulse welding, which can fully stir the molten pool, and improve the forming and performance of the weld. In this study, a mathematical model was developed using the response surface method (RSM) with three main process parameters (welding current, peak-to-base ratio, welding speed) as input values with three key geometric characteristics parameters, and the mechanical properties of the resulting welds were investigated. The results showed that the parameter model developed in this study had less error and could optimize the process parameters better; the optimal process parameters (welding current, peak-to-base ratio, welding speed) were 160 A, 39.93%, and 83.11 cm min−1, respectively. The improved welding parameters result in better mechanical properties and better weld profile, and more stable welding process. As a result, this experiment provides a new perspective for process parameter optimization and mechanical properties research for weld manufacturing.

Post-earthquake Dynamics of Bridge Structures using New Particle Dampers – A Case Study of the Nujiang River Bridge

In this study, a new mechanical model, named particle damping mechanics model (PU_SPD), is proposed to study the damping problem of bridge structures. The model takes the Nujiang River Bridge as a case study, and explores the mechanism of force action by analyzing the time domain vibration characteristics and frequency domain of the excitation force, vibrating body (bridge structural properties) and particle damping. the PU_SPD model and its calculation method can intuitively and scientifically describe the damping dissipation characteristics of a vibrating beam under the action of particle damping, avoiding the tedious process of parameter iterative solution and improving the computational efficiency. In addition, the damping influence law of particle damping on the beam structure is derived through the analysis of transfer function and damping level. The study also proposes an optimal design method for PU_SPD damping parameters under dynamic loading of the bridge, and its performance parameters are analyzed and verified, and compared and validated with the time-domain analysis method. The results show that the PU_SPD mechanical model based on time-frequency domain analysis can intuitively reflect the damping dissipation mechanics with high accuracy, clear solution process and reasonable and accurate parameter optimization analysis method. PU_SPD has a wide frequency range, good effect and stability, and has a good prospect of application in engineering vibration and noise reduction.

Parameter optimization analysis of rotary electromagnetic vibration energy harvester for performance enhancement under free vibration

In this paper, three new important aspects of rotary electromagnetic vibration energy harvesting technology (RE-VEH) are concerned and investigated: (i)vibro-electric coupling mechanism of the RE-VEH system is studied through theoretical modeling; (ii) quantitative analysis of system parameters based on numerical simulation method is carried out for the optimal design of RE-VEH; and (iii) dynamic power output performance of the RE-VEH system in free vibration is discussed. The parameter adjusting methods of the RE-VEH system in free vibration mode are obtained through theoretical analysis and numerical simulation. The experimental results show that the power output performance of RE-VEH in free vibration mode matches the numerical simulation results. The simulation and experimental results show that the maximum voltage output and power output of the RE-VEH with different structure parameters under free vibration can be up to the level of 100∼101 V/watt. The above results indicate that RE-VEH in a free vibration environment has significant energy output performance.

Parametric optimization and exergy analysis of a high mach number aeroengine with an ammonia mass injection pre-compressor cooling cycle

The Ammonia mass injection pre-compressor cooling (Ammonia MIPCC) cycle provides a substantial potential for the development of a high Mach aeroengine. To evaluate performance and analyze exergy of Ammonia MIPCC aeroengine, the parameter matching modeling method and Sequential Quadratic Programming (SQP) optimization are applied. These proposed methods can realize the constraints of compressor outlet temperature, combustor outlet temperature, power balance and flow conservation, thereby optimizing the specific impulse performance. Results show that the optimal operating line (OOL) of the Ammonia MIPCC aeroengine can be divided into two paths: the temperature limit operating line and the maximum specific impulse operating line. Moreover, the OOL of the Ammonia MIPCC aeroengine is always in a high exergy utilization state. When the ammonia rate increases from 0 to 0.08, the changes in exergy reduction rate, specific impulse and specific thrust corresponding to OOL at Ma 3.0 are 18.89%–31.83%, 2347.47 to 1113.56s, 768.91–953.47 N/(kg/s), respectively. Additionally, results show that the cycle with lower inflow cooling requirements can improve economy. In summary, parameter optimization and exergy analysis help to determine the working characteristics of high Mach number Ammonia MIPCC aeroengines, enhance the engine thrust performance and extend the operating envelope.

Performance Improving of Wind Power Generation Systems Through Parameter Optimization and Dynamic Analysis of the Speed-Regulating Differential Transmission

Abstract Hybrid drive wind power generation systems (WPGSs) equipped with speed-regulating differential mechanisms (SRDMs) have emerged as a promising solution for integrating large-scale wind energy into the power grid without the need for partially or fully rated converters. This article presents a comprehensive study on the dynamic analysis and parameter optimization of the SRDM-based transmission, with the aim of providing a sound foundation for the design and performance improvement of hybrid drive WPGSs. This study first formulates the kinematics, power flow, and mechanical efficiency of the SRDM and then proposes an effective parameter configuration model for optimizing the speed ratios of the key link units. The objective function is set as the minimum peak power required for speed regulation by the SRDM. Furthermore, to deal with the unique mechanical features such as dual power inputs, continuously variable transmission, and time-varying steering mechanism, an appropriate nonlinear dynamic modeling method of the SRDM transmission is developed. The torsion–translation vibration equations are derived and solved using the Runge–Kutta numerical integral method, considering randomly changing wind speed inputs and time-varying internal/external excitations. Results reveal that the sun gear experiences severe vibrations with the maximal and average vibration displacements of 0.563 mm and 0.112 mm, respectively, in the circumferential direction, while the planet gear exhibits complex frequency responses. Finally, specialized case studies are demonstrated to verify the proposed approaches, showing the satisfactory on-grid operating performance of the proposed SRDM-based WPGSs.

Enhancing the Seismic Performance of Adjacent Building Structures Based on TVMD and NSAD

Under the action of an earthquake, the adjacent building structure will have a large displacement and even cause damage to the structure. Structure displacement can be suppressed by adding a tuned viscous mass damper (TVMD) and negative stiffness amplifier damper (NSAD) between adjacent structures. This paper deduces the motion equation of adjacent building structures under earthquake action. The transfer function of the vibration control system is obtained using Laplace transform. The parameter optimization analysis of the structural vibration control system is carried out through H2 norm theory. The vibration control performance of the TVMD vibration control system and NSAD vibration control system is studied by taking two adjacent building structures composed of single freedom building structures as an example. The results show that the two vibration damping devices proposed in this paper can play the role of vibration control. The influence of the same parameters on the two structures is not completely consistent. Under seismic excitation, the NSAD control system has better displacement control ability than the TVMD control system.

Simultaneous adsorption of methylene blue and amoxicillin by starch-impregnated MgAl layered double hydroxide: Parametric optimization, isothermal studies and thermo-kinetic analysis

Textile and pharmaceutical effluents contain significant amounts of dyes and antibiotics, which pose a serious threat to the ecosystem when discharged directly. Therefore, they should be treated by facile treatment techniques using low-cost materials. Layered double hydroxide (LDH) and its hybrids have emerged as robust and economic adsorbents for water treatment. Herein, magnesium/aluminum LDH and its starch-based composite were synthesized by a co-precipitation technique. The physicochemical features of the developed adsorbents were thoroughly characterized using various analytical tools. The developed materials were tested for the eradication of methylene blue (MB) and amoxicillin (AMX) in batch mode adsorption by varying operating conditions. Adsorption performance depends on the solution's pH. Under optimum adsorption conditions of pH 11, adsorbent dosage of 50 mg/L, and treatment time of 120 min, starch-impregnated MgAl-LDH exhibited maximum MB and AMX adsorption capacities of 114.94 and 48.08 mg/g, respectively. The adsorption mechanism states that hydrogen bonds and weak van der Waals forces are responsible for the removal of pollutants by the developed materials. Moreover, equilibrium and kinetic studies revealed that the removal of dye and antibiotic followed the Freundlich and Langmuir models with the pseudo-second-order reaction kinetics, respectively. The spent adsorbents were regenerated using 0.1 M HCl (for MB) and methanol (for AMX) eluent, and reusability studies ensured that the developed adsorbents retained their performance for up to four consecutive adsorption/desorption cycles. MgAl-LDH and its starch-based hybrid could thus be used to effectively remove organic contaminants from wastewater streams on a commercial scale.