Dynamic Performance Evaluation Research Articles

Dynamics Modeling and Motion Evaluation of a Near-Ground Tethered Balloon Cable System under Severe Wind Environments

Weather survival poses a significant challenge for the utilization of tethered balloons. The dynamic modeling of tethered balloon systems presents challenges due to the flexible nature of the cables and the intricate nature of gust forces. The present study introduces a new approach for modeling near-ground tethered balloon systems, which enables the analysis of their dynamic responses and performance evaluation under complex boundary conditions. First, finite cylindrical rigid bodies that are joined together by bushing forces to describe the dynamics of the tethered cable. The properties of the flexible cables under severe bending and translation can be illustrated by the dynamics model. Second, a three-dimensional dynamics model based on the multibody dynamics theory is created to deal with the interaction of the tethered balloon system and flexible cables. The dynamic responses of the tethered balloon system under challenging operating conditions are investigated, focusing on the number of cable segments and the place and direction of gust wind impacts. This model allows for precise assessment and optimization of the system’s overall performance to improve weather resistance. The results show that compared to computational fluid dynamics (CFDs) methods, the multibody system dynamics-based balloon model improved the solution time by 80%, with a pitch angle deviation of only 0.0016°. Moreover, the bushing model effectively reduced cable force and enabled accurate reflection of the system’s motion characteristics.

Integration and capacity optimization of molten-salt heat storage in coal-fired power plant with carbon capture system

Developing a new generation of economical, low-carbon, and flexible coal-fired power plants (CFPP) is crucial for achieving the low-carbon transformation of the energy industry. Deploying molten salt heat storage (MSHS) in the CFPP can effectively enhance its peak shaving capability and reduce the limitations of carbon capture on wide range operation of the plant. To this end, this paper proposes four integration schemes for MSHS into the power plant-carbon capture system. The thermal efficiencies, exergy efficiencies, and peak shaving capabilities of the entire plant under different integration schemes are evaluated and compared. The results indicate that the optimal integration scheme involves utilizing hot reheat steam to heat the cold molten salt and further provide heat for the carbon capture system during the heat charging process and utilizing hot molten salt to heat the outlet water of the feed water pump during the heat discharging process, which achieves the highest thermal efficiency of 38.00 % and exergy efficiency of 37.09 % across the entire cycle. A novel integrated design, scheduling, and control optimization (IDSCO) method is proposed to find the optimal capacity configuration of MSHS, in which the investment, maintenance, fuel, carbon emission, and long-timescale and short-timescale load tracking deviation penalty costs are fully considered. A design parameter-aware control system is developed based on a multi-parametric programming model predictive control approach to ensure a fair evaluation of closed-loop dynamic performance under different configuration capacities. The simulation results demonstrate that the deployment of MSHS can significantly enhance the flexibility of the power plant-carbon capture system and the proposed IDSCO approach can reduce 17.05 % of load tracking deviation penalty cost and 1.38 % of totalized cost compared to the conventional configuration approach. This paper effectively leverages the potential of MSHS in enhancing the operational flexibility of CFPP-PCC system, thereby providing useful guidance for future deployment of MSHS within CFPP-PCC system.

Dynamic Modeling and Performance Evaluation of Using Spacer Fabrics as Shock Absorbers in Helmet of the Car Passenger

Dynamic Modeling and Performance Evaluation of Using Spacer Fabrics as Shock Absorbers in Helmet of the Car Passenger

Deployment Dynamic Modeling and Driving Schemes for a Ring-Truss Deployable Antenna

Mesh reflector antennas are widely used in space tasks owing to their light weight, high surface accuracy, and large folding ratio. They are stowed during launch and then fully deployed in orbit to form a mesh reflector that transmits signals. Smooth deployment is essential for duty services; therefore, accurate and efficient dynamic modeling and analysis of the deployment process are essential. One major challenge is depicting time-varying resistance of the cable network and capturing the cable-truss coupling behavior during the deployment process. This paper proposes a general dynamic analysis methodology for cable-truss coupling. Considering the topological diversity and geometric nonlinearity, the cable network’s equilibrium equation is derived, and an explicit expression of the time-varying tension of the boundary cables, which provides the main resistance in truss deployment, is obtained. The deployment dynamic model is established, which considers the coupling effect between the soft cables and deployable truss. The effects of the antenna’s driving modes and parameters on the dynamic deployment performance were investigated. A scaled prototype was manufactured, and the deployment experiment was conducted to verify the accuracy of the proposed modeling method. The proposed methodology is suitable for general cable antennas with arbitrary topologies and parameters, providing theoretical guidance for the dynamic performance evaluation of antenna driving schemes.

Evaluation of Accelerometer Dynamic Performance Based on Multiple Indices in the Time and Frequency Domain

Evaluation of Accelerometer Dynamic Performance Based on Multiple Indices in the Time and Frequency Domain

Research on High-Precision Dynamic Modeling and Performance Evaluation of Inertially Stabilized Platforms

Research on High-Precision Dynamic Modeling and Performance Evaluation of Inertially Stabilized Platforms

Dynamic performance evaluation of a magnetorheological damper-based sting support in wind tunnel tests

The sting support faces an issue of being prone to resonance due to its low-damping characteristics, which will compromise the accuracy of test data in wind tunnel experiments. Magnetorheological damper (MRD)-based tail support (MRSS) features varying stiffness and damping abilities, enabling it to suppress the vibration with random, time-variation characteristics in a self-adaptive way, and it also exhibits excellent fail–safe properties. This work aims to validate its controllability and fail–safe property in a wind tunnel environment. First, the natural frequency, root mean square (RMS), and power spectral density (PSD) of the designed MRSS’ response for random excitation were theoretically analyzed. Then, wind tunnel experiments were conducted to test the response under different attack angles, wind speeds, and test currents. Subsequently, the controllability and fail–safe property were demonstrated by analyzing the aircraft model response. Also, the variable stiffness and damping properties of MRD behind the observed phenomena were revealed based on the theoretical analysis. Results demonstrate that as the input current increases and the MRD’s stiffness continues to increase, the damping initially increases and then decreases. Increasing wind speed leads to a decrease in the MRD’s stiffness. Additionally, approximately 50% reduction in RMS and a multi-modal response attenuation was achieved.

Dynamic Performance Evaluation of Machine Foundations Using Multi-approach Investigation

Dynamic Performance Evaluation of Machine Foundations Using Multi-approach Investigation

Techno-economic analysis and dynamic performance evaluation of an integrated green concept based on concentrating solar power and a transportable heat pipe-cooled nuclear reactor

The nuclear-solar hybrid system (NSHS) is regarded as a promising solution to meet the growing energy requirements of remote areas. Currently, design schemes and parametric analyses for small-scale application scenarios are still limited. This study has proposed an innovative transportable micro heat-pipe cooled nuclear reactor (HPR) coupled with a concentrating solar power (CSP) system to achieve flexible load regulation. First, a dynamic simulation model for the NSHS is established in the Simulink platform, considering turbomachine off-design characteristics and the power-load matching dispatch principle. Then, techno-economic analyses are carried out to explore the exergy and capital cost flow processes. The results reveal that the NSHS shows clear seasonal features with the highest load cover rate of 98.31 % in summer and the lowest of 73.82 % in winter. The total exergy effectiveness of the NSHS is 29.4 %, with an average electricity cover ratio of 88.67 % and a solar energy penetration ratio of 13.32 %. The calculated LCOE is 80.84 $/MWh, and the payback period is 3.62 years. The life cycle emission of the system is assessed as 10.23 g CO2 eq./kWh. Compared with the solar standalone system, the hybrid system with higher efficiency faces challenges in high-temperature resistance and thermal insulation.

Dynamic Characteristics of M-Shape Metal Rubber-Coated Pipeline System: Numerical Modeling and Experimental Analysis

As a high-temperature resistant damping material, reducing vibration by coating with M-shape metal rubber (MMR) in a pipeline system is a promising solution due to its energy dissipation induced by micro dry friction between metallic wires. The main challenge for dynamic calculation and performance evaluation of elastic-porous metal rubber (MR) is derived from the intricate spatial network structure. In this work, the dynamic properties including acceleration admittance and insertion loss of the MMR-coated pipeline system were conducted by numerical simulation and experimental analysis. The constitutive models used to characterize hysteresis phenomena, including Yeoh and Bergström–Boyce models, were identified with different density parameters and adopted for steady-state dynamic numerical analysis. The sine sweep frequency test was conducted to verify the accuracy of the developed numerical model. The results indicate that the maximum error of stress–strain curve between numerical prediction and experimental measurement is 10.7%. In the frequency range of 0–1 500[Formula: see text]Hz, the insertion loss of the MMR-coated pipeline system is positively correlated with the density of MMR, as opposed to the coating distance of pipeline clamps and the influence of excitation force is minimal. Furthermore, the error of dynamic response of the pipeline system in low frequency between the experiment and simulation is 4.7%, indicating that the accuracy of the hysteresis model in predicting the dynamic characteristic of MR materials is effective.

Tolerance design of revolute clearance joints for aero-engine planar maneuvering mechanism by uncertain dynamic performance evaluation

Tolerance design of revolute clearance joints for aero-engine planar maneuvering mechanism by uncertain dynamic performance evaluation

Dynamic analysis and performance evaluation of inerter fractional nonlinear quasi-zero stiffness isolator on a multi-span bridge under moving load

In this paper we propose a new vibration isolator system, which combines the advantages of a quasi-zero stiffness (QZS) isolator, a damper exhibiting fractional properties and an inerter, to reduce the vibrations of a multi-span continuous beam bridge excited by moving loads. The inerter produces a fictitious mass amplification effect to improve the controller performance and the fractional order takes into account the previous state of the viscoelastic material. After formulating the dynamics equation using beam theory, the amplitude response is determined analytically using the averaging method. The results obtained from the analytical study are validated using the direct numerical simulation method (Newton–Leipnik method). By comparing the isolation performance of the FQZS (fractional quasi-zero stiffness) isolator and the IFQZS (inerter fractional quasi-zero stiffness) isolator, it is shown that the addition of inertance can significantly suppress the tendency of the curve to slope to the right, allowing us to have a wider isolation frequency range on force transmissibility while improving the efficiency of the isolator. One also shows that increasing the fractional parameter contributes to a decrease in the vibration amplitude of the structure, the amplitude of the force transmitted and the area in which unstable solutions appear. However, beyond a certain value of the fractional parameter, we observe an increase in the latter. In order to further extend the study, bifurcation diagram, phase portrait, time history and power spectral density are explored.

Dynamic behaviour and performance evaluation of a biomass-fired organic Rankine cycle combined heat and power (ORC-CHP) system under different control strategies

The dynamic behaviour and performance evaluation of a biomass-fired organic Rankine cycle combined heat and power (ORC-CHP) system under two different control strategies are investigated in this study. The dynamic model is established, while the dynamic characteristics of key operating parameters (superheat degree, evaporating pressure and mass flow rate) with the step change of heat source temperature are examined. The effects of controlled superheat degree and controlled expander shaft work on dynamic behaviours of thermodynamic, economic and environmental performance are discussed and compared under different control methods (feedforward active control, PID passive control and combined control). Results indicate that the superheat degree is significantly influenced by the heat source temperature under the without control strategy, with the variation reaching 8.4 K. The combined control method exhibits the best control performance with overshoot and control response times of 1.2 K and 12.3 s, respectively. Compared to without control, the expander shaft work and ORC thermal efficiency of the control strategy of superheat degree increase by 3.2 kW and 0.8 %, while that of the control strategy of expander shaft work increase by 1.0 kW and 0.3 %, respectively. The control strategy of superheat degree presents a significant improvement in the economic and environmental performance of the biomass-fired ORC-CHP system. This study is expected to provide better guidance for the practical operation and control of biomass-fired ORC-CHP systems.

Dynamic Performance Evaluation of N-channel MOSFET under Gamma Irradiation

Dynamic Performance Evaluation of N-channel MOSFET under Gamma Irradiation

Optimized process intensification through dynamic performance simulation and evaluation of treatment alternatives for a wastewater treatment plant in Toronto

In this study, a comprehensive plant-wide model of the North Toronto Treatment Plant (NTTP) was developed, focusing on improving operational efficiency and capacity utilization. NTTP, with a rated capacity of 45 MLD, is currently operating at about 18 MLD with treatment processes including physical units (incorporating four primary settling tanks), chemical precipitation (for phosphorus removal using ferrous chloride), and biological processes (utilizing eight plug-flow conventional activated sludge (CAS) aeration tanks), and two sets of final clarifiers. Utilizing Biowin 6.2, the study constructed and calibrated a mechanistic model based on historical plant records and extensive sampling campaign data gathered from July to August 2022. The performance of various process configurations under different operational and seasonal conditions was evaluated. It was observed that the Ludzack-Ettinger (L-E) configuration demonstrated enhanced performance in terms of Environmental Compliance Approval (ECA) objectives and cost-efficiency compared to the CAS process. However, the L-E configuration posed challenges related to the final clarifier loading. The State Point Analysis (SPA) conducted within the study emphasized the effectiveness of the Membrane Aerated Bioreactor (MABR) in producing high-quality effluent, while also reducing the burden on the final clarifiers. This research provides a foundation for potential upgrades to NTTP, leveraging existing infrastructure to approach its full rated capacity while maintaining adherence to current ECA objectives.

Enhancing shipyard transportation efficiency through dynamic scheduling using digital twin technology.

Uncertainties, such as road restrictions at shipyards and the irregular shape of blocks, pose challenges for transporter scheduling. Efficient scheduling of multiple transporters is critical to improving transportation efficiency. The digital twin (DT) technology offers numerous benefits, enabling interactions between the virtual and real worlds, real-time mapping, and dynamic performance evaluation. Based on DT technology, this study proposes a dynamic scheduling approach for cooperative transportation utilizing multiple transporters. The scheduling problem for multiple transporters is addressed and modeled in this study, considering factors such as block size and transporter loading. To solve this problem, a framework of DT-based multiple transporters system is established in a virtual environment. By inputting block information into this system, a solution is generated using transporter scheduling rules and interference detection methods. Experimental comparisons are conducted in this paper, exploring various scenarios with different number of tasks and the application of DT. The results demonstrate that the proposed approach effectively enhances transportation efficiency and improves ship construction efficiency. Hence, this study expands the application of DT technology in dynamic scheduling of transportation in shipyards and provides new ideas for shipbuilding company managers.

Dynamic Performance Optimization of Monorail Rapid Transit Formation Vehicles Based on Improved Artificial Potential Field Algorithm

This paper presents a new type of monorail rapid transit vehicle, which can operate in formation. In order to optimize the dynamic performance of the formation vehic-les when passing through the small radius curve, this paper first analyzes the structure of the new monorail rapid transit vehicle, and establishes the vehicle dynamic model and multi-body dynamics simulation model. Then the improved artificial potential field algorithm is used to build the formation vehicle operation controller. Finally, the dynamic performance evaluation index of the new mono-rail rapid transit formation vehicle is formulated, and the formation vehicle passing through the small radius curve scene is simulated. The simulation results show that the controller of the formation vehicle with dynamic optimi-zation control can effectively optimize the load transfer coefficient of running wheels, unbalanced centrifugal acce-leration and roll angle of vehicle body when passing thro-ugh the curve. Through this control method, the dynamic performance of formation vehicles passing through small radius curve lines can be optimized.

Study on the Dynamic Performance and Damage Evaluation of Rubber-Modified Non-Autoclaved Concrete Pipe Piles under Axial Drop Hammer Impact

In order to improve the weak impact resistance of non-autoclaved concrete pipe piles, this study replaced sand in the concrete with rubber particles of different volume contents to obtain rubber-modified non-autoclaved concrete pipe piles (with volume contents of 0%, 5%, 10%, and 15%). The dynamic impact response characteristics of rubber-modified non-autoclaved concrete pipe piles were obtained through large-scale axial hammer impact experiments. The results indicate the following. (1) Non-autoclaved concrete pipe piles without rubber additives were prone to expansion deformation instability under impact. When the rubber content was 10%, the expansion deformation of the piles was the weakest, and the state was the most stable. (2) When the impact energy exceeded 48 kJ, the deformation energies of piles with 5% and 10% rubber contents significantly increased. (3) The damage levels of the piles after hammer impact were classified into four grades: no damage, mild damage, moderate damage, and severe damage. When the impact energy was greater than or equal to 48 kJ, rubber-modified non-autoclaved concrete pipe piles exhibited damage. The zone with no damage for piles with 10% rubber content was the smallest, making it less prone to damage under impact loads. The rubber-modified non-autoclaved concrete pipe piles with 10% rubber content not only had excellent impact resistance but also utilized the advantages of being environmentally friendly and energy-saving. They filled a certain knowledge gap in green building materials.

Control parameter optimization of underwater gliders with uncertainty using hierarchical optimization method and interval analysis theory

This article attempts to solve the engineering optimization problem for control parameter configuration of underwater gliders with parameter uncertainty. The optimization objectives are maximizing the glider energy utilization rate and average voyage velocity; design variables include the net buoyancy adjustment amount and movable mass block translation amount; and uncertain parameters include the glider control parameter errors, manufacturing errors and sensor measurement errors. First, a dynamic simulation-based performance evaluation model of the glider is established, and interval number order theory is used to quantify the uncertainty. Then, surrogate models of the performance evaluation model are established, and the Sobol’ method-based sensitivity analysis is executed to identify the key uncertain parameters. Thus, a hierarchical optimization framework is introduced, and its system level and sub-level are used for determining optimal control parameter values and performance evaluation parameter intervals, respectively. Finally, optimization calculation is executed under different parameter configurations, and some rules are summarized.

Dynamic Performance Evaluation and Optimization of Common HFAC Bus Lightweight MMC-SST

Dynamic Performance Evaluation and Optimization of Common HFAC Bus Lightweight MMC-SST