Influence Of Design Parameters Research Articles

Investigation of the Influence of Design Parameters on the Strength of Steel–Concrete Composite Shear Walls by Finite Element Simulations

In this paper, the influence of design parameters on the strength of steel–concrete composite shear walls is investigated by means of finite element (FE) simulations. The shear wall typology studied in this paper consists of multiple composite plate shear wall-concrete encased on one or both sides of the plates. The FE models include contact technology to capture debonding between concrete and steel, tensile cracking in concrete, and large deflection theory involving local instabilities. Some design parameters considered in this work are the height-to-width ratio of the steel plates and their thickness, number of steel plates, the cross-section of the columns, and the height-to-width ratio of the shear wall. Furthermore, a sensitivity analysis of the normalised shear strength per unit cost of structure for these design parameters is also studied. Our numerical predictions are validated successfully with experimental data reported in the literature, revealing the predictive capabilities of the model. The present results provide further insight into the structural behavior of steel–concrete composite shear walls and pave the way for the future development of more efficient and innovative steel–concrete composite systems.

Research on the Influence of Design Parameters on the Seismic Capacity of High Rise Prefabricated Structure Buildings

Building industrialization and resilience are the goals and trends of structural engineering development. Prestressed assembly design and construction is an effective way to achieve this goal. The birth of prefabricated buildings has met people's demand for diversified buildings from many angles. At the same time, prefabricated buildings have also broken the limitations of long construction time and low efficiency of traditional buildings, and gained broader development prospects in construction work. Compared with cast-in-place concrete structure, prestressed prefabricated concrete structure has the advantages of good performance, small residual deformation after earthquake, full use of high-strength materials to reduce self-weight, industrial production and fast construction speed. Each part of the prefabricated building can be disassembled and assembled. When designing the structure, it is necessary to consider the characteristics of the structural system, and set up the connection mode reasonably during assembly to ensure the stability of the structure. This paper expounds the influence of design parameters on the seismic capacity of high-rise assembled structure buildings, and puts forward the seismic design strategy of high-rise assembled structure buildings.

Anti-Tetrachiral Auxetic Structures Fabricated by Material Extrusion: Numerical and Experimental Investigation on Influence of Design Parameters on Mechanical Properties under Compressive Loading

Anti-Tetrachiral Auxetic Structures Fabricated by Material Extrusion: Numerical and Experimental Investigation on Influence of Design Parameters on Mechanical Properties under Compressive Loading

Energy performance of a hybrid DSF-inspired solar heating façade for office buildings

Double-skin façade (DSF) is a passive design strategy that enhances building energy performance and improves indoor thermal comfort. In addition, DSF has been proposed as a hybrid façade that uses a cavity to preheat fresh air supplied to an air-handling unit (AHU) to reduce energy consumption for heating. However, to the authors' knowledge, there is no study about the design of DSF tailored for the hybrid system application yet. Therefore, this study focuses on the usability of DSF as a hybrid system and evaluates the performance. First, parametric analysis of the hybrid solar heating façade geometry and thermal properties of glazing and absorber materials was performed to identify the most influencing design parameters. Second, the multivariate linear regression (MLR) model was developed to predict the performance of all parameters comprehensively affecting the hybrid solar heating façade. Finally, the performance of various design alternatives for hybrid solar heating façade that provide the minimum fresh air supply was evaluated through case studies. The analysis results confirmed that the hybrid solar heating façade can reduce the heating energy due to the preheating effect by up to 38%.

Interface slip of steel–concrete composite beams reinforced with CFRP sheet under creep effect

Under the creep action of composite steel and concrete beams reinforced by carbon-fiber-reinforced polymer (CFRP) sheet, the face of the CFRP sheet, steel beam, and concrete slab beam produce relative slip. This slip affects the interface interaction, reduces the bearing capacity and stiffness of the members, and increases the deformation. In this paper, elastic and energy methods are used to analyze the interface forces between steel beams and concrete slabs reinforced by CFRP sheeting under the action of concrete creep. The calculation formulas for interface slip, axial force, and incremental deformation are established. The influence of design parameters on the mechanical properties of the interface is analyzed. Results show that the increments in interface slip, axial force, and deformation are zero on the 28th day. With increasing age, the increments in interface slip, axial force, and deformation gradually increase, and the increase is large in the first 100 days; it basically remains unchanged during the time interval from 100 to 1028 days. When the load increases by 5 N/mm (5 kN), the slip increments increase by approximately 0.004 mm, 0.002 mm, and 0.002 mm. The increments in axial force are approximately 19.4 kN, 15.9 kN, and 16.1 kN. The deformation increments increase by approximately 1.7 mm, 1.1 mm, and 0.6 mm.

Multi-objective optimization of an air cooling battery thermal management system considering battery degradation and parasitic power loss

The battery thermal management system (BTMS) can effectively ensure that the batteries work in a safe temperature range and solve the problems caused by high temperature. This paper investigates an air cooling BTMS with 32 cylindrical lithium-ion batteries (LIBs). Previous BTMS studies pay little attention to cost, this work focuses on the economic cost to address the cost problem caused by the parasitic power consumption of BTMS. First, the battery degradation model is established, and the cycle life of the battery is determined through capacity loss. Second, the computational fluid dynamics (CFD) simulation is used to study the influence of design parameters on the maximum temperature (MT) of the battery module and the pressure drop. Then, this study proposes to use cyclical cost (including battery cycle life and parasitic power loss) to evaluate the economy. The MT and cyclical cost are simultaneously considered as the optimization objectives to form an optimization model via the surrogate model method. Finally, two multi-objective optimization algorithms are used to drive the optimization process. The results suggest that the MT drops from 314.58 K to 314.22 K, while the cyclical cost drops from 0.92 €/cycle to 0.85 €/cycle, a reduction of 7.6 %. The developed method could improve the economy while ensuring the heat dissipation performance of the battery, which provides guidance for the design of BTMS to meet the needs of consumers.

Оценка влияния факторов эксперимента при исследовании динамической погрешности двухкомпонентного датчика угловой скорости

Angular rate sensors are widely used in various technology areas, especially in aviation and rocket technologies. Angular rate sensors are installed in aircraft stabilization, orientation and navigation systems to determine the object angular position and control. In addition, they could be introduced in the automatic control systems of a moving object to enter a signal proportional to the angular rate in the control function or to damp the object oscillations occurring under the action of angular or linear overloads. Various design schemes of angular rate sensors are currently known to perform their functionality with required accuracy in the given frequency range. For them, the influence of design parameters and feedback loop on the accuracy of a device under conditions of dynamic operational influences was studied sufficiently. Biaxial angular rate sensor built on the basis of a dynamically tuned gyroscope was considered, and the influence of various design and technological factors on the experimental estimated accuracy of its dynamic error was studied. Main probable factors leading to inaccuracies in determining this error in testing on the angular oscillations bench were considered

Mechanical property analysis and design parameter optimization of a novel nitinol nasal stent based on numerical simulation.

Background: A novel braided nasal stent is an effective alternative to nasal packing after septoplasty that can be used to manage the mucosal flap after septoplasty and expand the nasal cavity. This study aimed to investigate the influence of design parameters on the mechanical properties of the nasal stent for optimal performance. Methods: A braided nasal stent modeling method was proposed and 27 stent models with a range of different geometric parameters were built. The compression behavior and bending behavior of these stent models were numerically analyzed using a finite element method (FEM). The orthogonal test was used as an optimization method, and the optimized design variables of the stent with improved performance were obtained based on range analysis and weight grade method. Results: The reaction force and bending stiffness of the braided stent increased with the wire diameter, braiding density, and external stent diameter, while wire diameter resulted as the most important determining parameter. The external stent diameter had the greatest influence on the elongation deformation. The influence of design parameters on von-Mises stress distribution of bent stent models was visualized. The stent model with geometrical parameters of 25mm external diameter, 30° braiding angle, and 0.13mm wire diameter (A3B3C3) had a greater reaction force but a considerably smaller bending stiffness, which was the optimal combination of parameters. Conclusion: Firstly, among the three design parameters of braided stent models, wire diameter resulted as the most important parameter determining the reaction force and bending stiffness. Secondly, the external stent diameter significantly influenced the elongation deformation during the compression simulation. Finally, 25mm external diameter, 30° braiding angle, and 0.13mm wire diameter (A3B3C3) was the optimal combination of stent parameters according to the orthogonal test results.

Multi-objective optimization of parallel microchannel heat sink with inlet/outlet U, I, Z type manifold configuration by RSM and NSGA-II

Designing an effective parallel microchannel heat sink (PMCHS) is necessary for addressing the cooling challenges of high heat-dissipating electronics. This paper presents a shape optimization of PMCHS to minimize the thermal resistance and pressure drop for each U, I, and Z-type inlet/outlet manifold configuration with vertical intake and coolant delivery. The performance of PMCHS influencing design parameters, such as channel width, fin width, and channel height, is designed using the response surface methodology (RSM). In the present communications adopting the Artificial Neural Network (ANN) coupled NSGA-II method, a three-dimensional numerical simulation is executed to minimize the pressure drop and thermal resistance. Numerical simulation is performed using the finite volume method; the computational domain is taken as the entire microchannel system including the inlet/outlet plenum area, ports and microchannels. The overall analysis demonstrated that the pareto optimal design point has better hydraulic and thermal performances than the predefined design. The optimized design showed benchmark thermal resistance of 0.0306 ˚C/W, 0.0315 ˚C/W, 0.0316 ˚C/W and pressure drop of 3.1 kPa, 3.2 kPa, 3.19 kPa for U, I, Z configurations respectively.

Identification of the key design parameters of Zero/low energy buildings and the impacts of climate and building morphology

Load reduction is a fundamental means for achieving the zero/low-energy goal of buildings and for accomplishing carbon-neutrality. However, there is a lack of systematic and comparative study on the key design parameters of building envelopes, particularly under different climate conditions and building morphologies. In this study, the most influential design parameters of high-rise and low-rise buildings in different climate zones are identified by sensitivity analysis and the impacts of climate and building height are studied and compared. The sensitivity analysis is performed using Morris, while a total of thirty-five design parameters under five categories are considered. Five Chinese climate zones covering three typical climates in the world are researched. A wide range of local design and operation constraints are considered when evaluating the building performance in different climate zones. Furthermore, the key design parameters affecting winter thermal discomfort in the climate zones typically without heating provision are also identified. The impact of thermal bridge on building energy performance is further investigated. A remarkable finding is that the overhang is among the most important elements of the high-rise buildings in all climate zones concerned, while skylight is among the most influential elements of the low-rise buildings concerning building load. The results of the studies provide valuable references for the building envelope design for different climate conditions.

Global sensitivity analysis and optimisation of design parameters for low GHG emission lifecycle of multifamily buildings in India

In India, nearly 25% of citizens live in slums, unfit for a decent living. Replacing the existing residential building stock and the rapid development of the economy will significantly increase energy consumption and related greenhouse gases (GHG) emissions in the coming decades. Consequently, there is a high need of developing low lifecycle GHG emission, affordable and comfortable multifamily building designs, which can be widely implemented in the Indian construction market.The objective of this article is first to explore the most influential design parameters of the multifamily building located in the in: warm and humid (Bhubaneswar), hot and dry (Jodhpur), and composite (New-Delhi) climate zones of India on life cycle GHG emissions and indoor thermal comfort, and secondly, to perform a multi-objective optimisation considering the life cycle GHG emissions, life cycle cost and initial material investment cost based on the set of the most sensitive design parameters. The study combines a two-step global sensitivity analysis based on the Morris and Fast method with a multi-objective genetic algorithm integrated into one framework based on the parametric multifamily building model with extensive building performance simulations.The global sensitivity analysis results indicated that for all investigated locations: the apartment’s floor area, equipment load, windows-to floor ratio, mechanical ventilation airflow, and cooling temperature setpoint were the most influential design parameters in relation to the lifecycle GHG emissions. Finally, based on the multi-objective optimization, significant reductions in the range of 62–75% in terms of life cycle GHG emissions and 40–54% in terms of life cycle cost were achieved compared to the baseline 7-storey multifamily design scenario based on the minimum requirements of the Indian energy conservation code. At the same time, the initial material investment cost was 25–34% higher. The optimal set of the design strategies, resulting in the lowest life cycle GHG emissions and life cycle cost was found to be minimisation of the apartment’s floor area and windows to floor ratio, maximisation of the on-site renewable energy use, and design of a mechanical ventilation system combined with ceiling fans thus enabling the energy-efficient and thermally comfortable operation of the multifamily building with a high cooling temperature setpoint.

Cyclic loading tests and horizontal bearing capacity of recycled concrete filled circular steel tube and profile steel composite columns

To investigate the seismic performance of recycled aggregate concrete (RAC) filled circular steel tube and profile steel composite columns, the cyclic loading tests were conducted for eleven columns. The influences of design parameters on the seismic performance of composite columns were considered and investigated in detail, including the replacement percentage of recycled coarse aggregate (RCA), diameter to thickness ratio of circular steel tube, axial compression ratio, profile steel ratio and section form of profile steel. The failure characteristics, hysteresis loops, skeleton curves, stiffness degradation, ductility and storey drift ratio of columns were presented and discussed in detail. The results show that the column base forms an obvious plastic hinge under the combined action of horizontal cyclic loads and vertical loads, which belongs to the typical compression-bending failure. The hysteresis loops of composites columns are plump and spindle-shaped, indicating good energy dissipation capacity. With the increase of RCA replacement percentage, the ductility and energy dissipation capacity of columns decrease gradually, while the bearing capacity and stiffness of columns firstly reduce and then increase. The seismic performance of columns is significantly improved by the increasing wall thickness of circular steel tube and profile steel ratio. Increasing the axial compression ratio is unfavorable to the seismic performance of columns. The greater the axial compression ratio, the worse the ductility and energy dissipation capacity of column. Based on the test analysis and relevant specifications, the modified formulas on the horizontal bearing capacity of RAC filled circular steel tube and profile steel composite columns were proposed, and the validity of formula was verified by comparing with the test results.

Geometric analyses and experimental characterization of toroidal Miura-ori structures

Origami inspired structures are largely being recognized as efficient deployable structures that can serve multidisciplinary applications. This research focuses on the geometric analyses and quasistatic behavior of toroidal folding patterns based on the four-fold line origami concept. A sequential design process is presented to develop four-fold line toroidal origami structures from a flat sheet of paper, followed by a generalized design algorithm based on the mathematical formulation of the design process. The availability of the geometric design space is calculated considering the limiting values of the design parameters. Geometric analyses is performed to investigate the influence of design parameters on the packaging parameters and availability of the design space. A novel experimental setup is developed, and methodology is introduced to investigate the quasistatic behavior of the single story toroidal patterns. Then, this experimental approach is utilized to characterize the single story toroidal Miura-ori patterns (TMOPs) on the basis of their quasistatic behavior. Moreover, the quasistatic behavior of multi story TMOPs is investigated experimentally.

Experiments and simulation of the spreading behavior of fibre bundle in pneumatic spreader

Fibre spreading before impregnation process has great importance for production of non-woven fabrics. Thousands of filaments can be transported and spread by airflow in a pneumatic chamber. To better understand the lateral-spreading mechanism of the system, the generation and evolution of lateral dragging forces applied on fibre bundle are demonstrated through experiments and simulations. with the CFD model of the spreader and discrete element method (DEM), the spreading behavior of the filaments in the bundle are simulated. By parametrically analyzing the characteristics of fractal airflows, the influence of design parameters on the fractal airflow is analyzed and optimized. The simulation results are in good agreement with the experimental data. The width of the bundle has been widened almost 10 times, which has improved by 100 % compared with traditional mechanical spread method.

Machine learning-driven performance-based seismic design of hybrid self-centering braced frames with SMA braces and viscous dampers

A hybrid self-centering braced frame equipped with shape memory alloy-based self-centering braces (SMA-SCBs) and viscous dampers is proposed to achieve enhanced seismic performance. Based on the proposed hybrid strategy combining the contributions of SMA-SCBs and viscous dampers, this paper investigates the advantages of such hybrid self-centering braced frames in achieving the desired maximum inter-story drift under a considered seismic intensity. To this end, the influence of design parameters of SMA-SCBs and viscous dampers on hybrid self-centering braced frames is examined through parametric dynamic analyses of equivalent single-degree-of-freedom systems. The analysis results indicate that the post-yield stiffness ratio α and energy dissipation factor β of SMA-SCB, and the contribution of viscous damper show significant influence on the peak displacement responses of hybrid self-centering braced frames. The constant inelastic displacement ratio prediction model for hybrid self-centering braced frames is developed using machine learning algorithms. A performance-based seismic design method is subsequently proposed for the hybrid self-centering braced frames to achieve the target displacement responses based on the developed machine learning models. Two hybrid self-centering braced frames are designed based on the proposed design method. Nonlinear dynamic analyses are conducted to investigate the seismic performance of the designed structures. To highlight the advantages of the hybrid self-centering braced frames, another six-story self-centering braced frame with SMA-SCBs only is also studied in this paper. The analysis results indicate that all the designed hybrid self-centering braced frames can achieve the desired performance objective. Compared to the self-centering braced frame with SMA-SCBs only, the hybrid self-centering braced frames can achieve much smaller base shear demand and absolute floor acceleration responses.

Mechanistic Influence of Polymer Species, Molecular Weight, and Functionalization on Mucin–Polymer Binding Interactions

Improving both systemic and localized delivery of pharmaceuticals by optimizing the delivery vehicle properties is a major area of ongoing research. One such engineered property is mucoadhesion, wherein polymers are tailored to optimize polymer–mucin interactions to increase drug residence times and uptake efficiency. There are many examples of mucoadhesion as a drug delivery modality in the literature, yet the underlying mechanisms remain poorly understood, and its clinical translation is limited. Within this mechanistic lens, we found that nuclear magnetic resonance (NMR) is a powerful tool for uncovering polymer–mucin interactions. We investigated the influence of several polymer design parameters including molecular weight and repeating unit functionalization on mucoadhesion and uncovered several key findings in terms of the influence of these design parameters on polymer–protein intermacromolecular interactions. First, we probed individual polymer species including hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC), and carboxymethyl cellulose (CMC) and identified that molecular-weight-driven changes in the polymer–mucin interaction fingerprint result from perturbations in the polymer-specific binding complex. Specifically, we found that CMC and HPC complexes spatially reorient with increasing molecular weight, whereas HPMC complexes do not. We expanded this comparison to include functional group changes to the polymer repeating unit, where we showed that the addition of methyl groups to cellulose derivatives induces a unique binding fingerprint. Next, we expanded the mucoadhesive polymer series to include CMC, HPC, HPMC, poly(acrylic acid) (PAA), and poly((2-dimethylamino)ethyl methacrylate) (PDMAEMA) and observed a negative correlation between molecular weight and mucoadhesive interaction intimacy, highlighting the differences across polymer species. Finally, we explored polymers that lack mucin interactions to illustrate the limitations of polymer composition and molecular weight as predictors of mucoadhesive fate. Altogether, these experiments were used to report on mucoadhesive interactions at the atomic level and revealed that polymer design is dependent on both the availability and accessibility of mucoadhesive functional groups.

Electromechanical Modeling of Rolling Spherical Triboelectric Nanogenerators Considering Nonlinear Effects

AbstractIn this study, electromechanical coupling modeling and analysis of the rolling spherical triboelectric nanogenerators (RS‐TENG) considering nonlinear effects are conducted. After a brief review of the power generation mechanism, a capacitance‐fitting model of the RS‐TENG spherical electrode is proposed. By using the energy principle and differential equations of equivalent circuits, an electromechanical coupling model is established by considering the nonlinear variation in the dielectric sphere rolling angle. Using the harmonic balance method (HBM), the dynamic output characteristics of the RS‐TENG are analytically solved. Numerical integration and dynamic tests are used to verify the accuracy of HBM results. By comparing the changes in the RS‐TENG output performance with and without the nonlinear effect, it is shown that the model proposed in this study can effectively avoid the underestimation of the operation bandwidth (a relative increment of 43%) and overestimation of the maximum power density (a relative decrement of 32%), and significantly improve the accuracy of the RS‐TENG performance estimation. The influence of design parameters on the dynamic output characteristics of the system is discussed. The fitting coefficients obtained from the parameter influence discussion can be used as the basis for the RS‐TENG output performance design.

Impact of runner crown shape modifications on the onset of the precessing vortex core

In this experimental study, a passive flow control concept is provided to extend the stable part load operation regime by shifting the rise of the precessing vortex core (PVC), also known as vortex rope, toward lower mass flows respectively deeper part loads. A parametrized runner crown design working as a passive flow control device is derived. This control device aims for shifting the bifurcation point of the PVC to lower flow rates. To determine the most influential design parameters and derive an optimized runner crown design, a design of experiments (DoE) approach is used. This DoE approach is based on data obtained from differential pressure sensors inside the draft tube wall of a generic hydro turbine test rig using air as working fluid. By means of stochastic modeling, the growth rate of the PVC mode is derived from the statistics of the measured pressure signals. The growth rate is used to estimate the bifurcation point of the PVC characterized by a certain normalized flow rate. It is shown that the stable part load operation regime is extended by up to 25% due to the passive impact of the modified runner crown. Moreover, the operational range featuring considerable PVC-induced pressure oscillations is diminished and the pressure recovery of the draft tube is improved compared to the baseline case.

Multi-Objective Design Optimization of Cusped Field Thruster via Surrogate-Assisted Evolutionary Algorithms

Cusped field thrusters are an efficient cost-effective electric propulsion technology that offer promise for small spacecraft platforms. They offer various advantages, including simple design and low wall erosion, and hence long-life operation owing to high plasma confinement using permanent magnets over other electrostatic alternatives. Accurate physical modeling and performance characterization are crucial to achieve successful downscaling of cusped field thrusters while maintaining high performance. Multiobjective design optimization is performed by incorporating magnetic simulation coupled with an improved power balance model into evolutionary algorithms assisted by surrogate modeling, aiming to simultaneously maximize thrust, total efficiency, and specific impulse. Physical insights have been gained into key design factors to maximize thruster performance by probing into the plasma behavior inside the channel and the plume region. It has been found that altering the magnetic field distribution using an additional magnet can effectively enhance thruster performance by suppressing the plume divergence loss. Global sensitivity analysis has identified the anode current as the most influential design parameter on the performance parameters due to the active role it plays in the ionization process. Uncertainty analysis has found the considerable influence of the variations of anode potential and mass flow rate on those of thrust and specific impulse.

Analytical investigation on thermo hydraulic performance augmentation of triangular duct solar air heater integrated with wavy fins

ABSTRACT Present work deals with performance improvement of triangular duct solar air heater by integration of wavy fin on absorber plate. An analytical model has been developed for the investigation of design parameters such as fin pitch ratio with ranges 0.05–0.2 and fin amplitude ratio with ranges 0.025–0.125. MATLAB code is generated to solve the energy balance equations by iterative procedure. The influence of design parameters on effective thermal and thermal efficiency is presented and its influences are discussed. Increasing the fin pitch ratio decreases the thermal and thermo hydraulic efficiency drastically. The positive effect of fin amplitude ratio is observed; increasing of fin amplitude ratio improves the thermal efficiency and effective efficiency up to the critical Reynolds number. The peak thermal efficiency of 85% is observed and thermo hydraulic efficiency of 80.16% is found at fin pitch ratio of 0.05 and fin amplitude ratio of 0.125. The maximum thermo hydraulic performance enhancement is 15.7% as it compared simple conventional solar triangular duct air extractors. The design plots are developed to select the performance parameters to attain required temperature rise values.