bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Simulation Research on Thermal Energy Storage Characteristics of a Cascaded Packed Bed With Phase Change Material
Authors: Zhao Bingzhou , Wu Junjun , Fu Qian , Liao Qiang , Cheng Min 
Published: February 2024

Abstract
Latent heat storage technology is an efficient way of heat storage due to its high energy storage density and stable energy storage temperature. Cascaded latent heat storage (CLHS) is a promising technology to improve the heat transfer rate and energy efficiency in the packed-bed thermal energy system (PBTES). In this paper, a 1-D two-phase model is established to study the thermal performance of cascaded latent heat storage (CLHS) system. The study used energy and exergy analysis theories to investigate the effects of heat transfer fluid (HTF) flow rates, HTF inlet temperatures, and layout of PCMs on thermal performance of PBTES. The indexes of heat storage density, average heat storage rate, effective heat storage time and exergy efficiency are used to compare the performance of single-PCM and CLHS systems. The results show that the CLHS system has a higher heat storage and thermal density compared with single-PCM heat storage systems. The exergic efficiency of CLHS is 0.93, which is much higher than PBTES. And increasing the inlet temperature or fluid flow rate can be the effective way to improve the thermal performance of packed bed thermal energy system.
Energy Efficiency Improvement Through Pumping System Modeling and Analysis
Authors: Jones Spencer , Languri Ethan 
Published: February 2024

Abstract
In this paper, the operation of the raw water pumping system for a water treatment plant is redesigned to sequence pump operation and improve energy efficiency. Using field data for the pump system’s flow, power, and head pressure, the parameters for the new pump operation sequence are set. By defining the system operation to use the more efficient pumps to satisfy base load conditions, the system inefficiency is diminished. Secondly, field data analysis revealed a persistent overlapping of pump operation, where multiple pumps would operate at one moment only to cause an unnecessary increase in head pressure as required flow had already been achieved.
The system analysis uses the total system flowrate as its control parameter. In the new system operation, the most efficient pump is loaded to its best efficiency point (BEP) then the remainder flowrate is given to the following pumps based on their efficiency. With an absence of pump curves, a variable speed drive (VSD) speed versus motor power relation can be made to predict, with a polynomial data fit, the motor power at calculated VSD speeds. With system operation sequenced by efficient motors and keeping head pressure near constant, a decrease in energy usage of 29.6% is demonstrated over the duration of the field data.
The proposed system operation is shown to operate remainder flow rate pumps at partial loads below their minimum design flowrate, due to the need to keep total flowrate parameter constant. By highlighting these operation points below the minimum design flow rate, the flow rate must be increased to that minimum for the pump, thus proposed operation is simulated with a slightly increased average flow rate.
The pump system is comprised of 4 centrifugal raw water pumps, one 200 HP and three 150 HP, with an average annual flowrate of 9,200 GPM. The raw water pumping system moves raw water from the federally managed water source to the treatment plant. The proposed system operation would be performed by a motor controller capable of managing at least four pumps at different sites as one pump is separated from the other three pumps. The specifications defined by the analysis in this study would be parameters for the controller programming along with the predicted performance after controller implementation. Analytical characteristics of such controllers are discussed along with their effect on the total pumping system. Finally, the economic impact and carbon emissions reduction of the proposed operational design are discussed.
Development of a Novel Hybrid Soft Cable-Driven Parallel Robot
Authors: Ovando Ammy , Papendorp Sky , Ashuri Turaj , Amiri Moghadam Amir Ali 
Published: February 2024

Abstract
This paper reports on the development of novel hybrid soft cable-driven parallel robots (HSCP). As the growth and refinement of the soft robotic field progresses, new methods of soft robotic actuation and control will continue to be developed. While most of the existing soft robotic systems have a serial structure, soft parallel robots have received a lot of attention recently. This is due to the wide range of applications of these systems in different industries such as the medical and the food industry. To the best of our knowledge, most of the existing soft parallel robots have active flexible legs. However, in this work for the first time, we have proposed a novel soft parallel robot with only passive flexible legs. In our hybrid design the stiffness of the robot is maintained through the passive soft legs and the actuation is based on a cable-driven mechanism. This will simplify the design and modeling of the robot. As an example of our design approach, a 6 degrees of freedom (DOF) hybrid soft parallel robot is designed which resembles the rigid Stewart mechanism. The mechanics of the robot are unique, being controlled only through cable actuation through six servo motors positioned around the base of the robot. The supports which were 3D printed with deformable Ninja Flex filament supply a nonlinear force to the robot, combined with the cable control enabling the robot to be able to execute basic movement within the workspace as well as being safer for human-machine interaction due to the soft support system. This paper also compares the kinematics and controls of this new robotic system to a typical rigid steward robot.
Material Model Parameters Optimization in Liquid Mercury Target Dynamics Simulation With Machine Learning Surrogates
Authors: Lin Lianshan , Tran Hoang , Radaideh Majdi I. , Gorti Sarma , Simunovic Srdjan , Jiang Hao , Winder Drew , Cousineau Sarah 
Published: February 2024

Abstract
A pulsed spallation target is subjected to very short (∼0.7μs) but intense loads (23.3 kJ) from repeated proton pulses, which knock away neutrons from the mercury atoms’ nuclei for a wide range application in physics, engineering, medicine, petroleum exploration, biology, chemistry, etc. The effect of this pulsed loading on the stainless-steel target module which contains the flowing mercury target material is difficult to predict not only due to its short but intense explosive-like physical reaction, but also the nonlinear material behavior of the liquid mercury in the structure. Injecting small helium bubbles in the mercury has been an efficient method of mitigating the pressure wave at high power level stage. However, prediction of the resultant loading on the target is more difficult when helium gas is intentionally injected into the mercury. A 2-phase material model that incorporates the Rayleigh-Plesset (R-P) model is expected to address this complex multi-physics dynamics problem by including the bubble dynamics in the liquid mercury. A parameter sensitivity study was firstly employed to understand their impact on the simulation strains. The investigated parameters included E, μ, γ, σ, n, VFgas, and gas cumulative volume curve control parameters a and b. Verification and validation results from sparse polynomial expansions (SPE) method and directional Gaussian smoothing (DGS) optimization show that the surrogate model had training error of ∼7% and validation error of ∼15%, indicating that machine learning methods and surrogate models can help optimize the uncertain parameters in the complex 2-phase material model. This approach is expected to fill the knowledge gap between unknown liquid-gas mixture material model and measured vessel strain responses.
Effect of Nonlinearities on the Vibration Reduction Performance of a System With Multiple Nonlinear Tuned Mass Dampers
Authors: Ekici Yigitcan , Cigeroglu Ender 
Published: February 2024

Abstract
In this study, a single-degree-of-freedom structure with multiple nonlinear tuned mass dampers is investigated. A sinusoidal excitation is assumed to be applied to the structure. In order to obtain the results, a nonlinear mathematical model of the general system is obtained in the form of a set of nonlinear ordinary differential equations. Dry friction and cubic stiffness nonlinearities are considered for the nonlinear terms. To obtain steady-state frequency responses of the system, these nonlinear ordinary differential equations are transformed into a set of nonlinear algebraic equations by using Harmonic Balance Method. Fourier transformation is used in the calculation of the Fourier coefficients of the nonlinear forcing terms. Then, numerical solutions to the resulting nonlinear algebraic equations are obtained using Newton’s Method with Arc Length Continuation. The effect of the number of tuned mass dampers and their arrangement, i.e. in series or in parallel, on vibration reduction is observed by performing optimization on several cases and comparing them. In order to observe the separate and combined effects of the nonlinearities, and the number of tuned mass dampers used, several case studies are carried out using optimized case parameters with different combinations of the nonlinearities. The results of these case studies and the linear model are compared with each other to see the effect of the nonlinearities. Additionally, results of the system with optimum nonlinear tuned mass dampers are compared with that of the optimum linear tuned mass dampers and the effect of nonlinearities are discussed.
Optimization of the Flow Parameters for a Liver Organ-on-a-Chip Computational Model
Authors: Pinto Edgar , Carvalho Violeta , Rodrigues Nelson , Rodrigues Raquel O. , Lima Rui A. , Teixeira Senhorinha 
Published: February 2024

Abstract
The organ-on-a-Chip (OOC) concept appeared intending to increase the efficiency and effectiveness of R&D activities, and open doors to precision and personalized medicine. However, for such devices to provide adequate results, they must mimic a specific human microenvironment with great accuracy. In the present work, a computational model of an organ-on-a-chip model was developed and optimized by evaluating the effectiveness and characteristics of some optimization methods. To perform the optimization and simulation, a geometry appropriate to the needs was first designed, having in base the current literature. After that, a mesh set capable of maintaining a balance between the accuracy of the results and computational performance was generated and a mesh study was conducted. Then, the simulation and optimization were performed. The latter was conducted by applying two different methods, the Multi-Objective Genetic Algorithm (MOGA) and Nonlinear Programming by Quadratic Lagrangian (NLPQL), for later comparison of results. Bearing in mind the hemodynamics in the liver, the goal of this optimization was to minimize the organ model blood flow mean velocity, in order to allow the adequate transfer of substances between the blood and liver cells.
Effect of Wear on the Forced Response of a Shrouded Blade
Authors: Cardak Aykut , Cigeroglu Ender 
Published: February 2024

Abstract
Dry friction damping is a commonly used approach in reducing resonant amplitudes in turbomachinery vibrations to prevent High Cycle Fatigue (HCF) failure of the blades in turbines or compressors. Intentional friction contact provides additional damping to the overall system by means of dry friction; however, predicting the forced response of frictionally constrained structures can be challenging due to the nonlinear nature of the problem. Although previous studies have worked on designing and mathematical modelling of various friction dampers, the effect of cumulative wear degradation on the structure over the operational lifetime is often underestimated. In this paper, the finite element model of a shrouded blade is used for this purpose as a case study. Harmonic Balance Method (HBM) in conjunction with Receptance Method (RM) is utilized to formulate the nonlinear algebraic equations of motion which are solved in frequency domain. In this study, one dimensional dry friction element with normal load variation is used in modeling friction contact. Alternating Frequency Time (AFT) method is used to obtain the harmonic coefficients, also known as Fourier coefficients, of the nonlinear forces introduced by frictional contact. Additionally, the well-known wear-energy method, which predicts the wear degradation at the contact interface is coupled to the nonlinear forced response analysis. This study aims to investigate how wear affects the dynamic response, performance, and reliability of the shrouded blade case study considered.
Heat Transfer and Combustion Processes in the OSU Calorimeter for Rate of Heat Release Predictions
Authors: Cappello Garrett , Farouk Bakhtier 
Published: February 2024

Abstract
Various calorimetric devices and measurement methods have been used historically in obtaining heat release rates of materials. A comprehensive ANSYS-Fluent computational fluid dynamic model for the full-scale OSU (Ohio State University) reactor is under development for the prediction of the flow, heat transfer and heat release characteristics of the reactor. The validated model will serve as a benchmark for providing uniformity in predictions of the OSU reactors located in different laboratories. A validated model will also provide better understanding of the flow and heat transfer characteristics in the OSU reactor.
In-Situ Shear Exfoliation of Graphene From Graphite Polymer Nanocomposites for Lung and Heart Motion
Authors: Rahman Md Ashiqur , Salam Md. Abdur Rahman Bin Abdus , Ashraf Ali 
Published: February 2024

Abstract
Graphene-based nanocomposites have become attractive for different applications such as energy storage, sensors, biomolecule detection, biomedical, healthcare, and wearable devices due to their unique mechanical, electrical, and thermal properties. However, using commercial graphene for making nanocomposite devices can be expensive, and fabricating nanocomposites can be challenging due to impurities while transferring graphene to elastomer composites. In this study, we used a simple, inexpensive in-situ shear exfoliation method to produce graphene from graphite directly within the elastomer. As the graphene in the elastomer reached beyond its percolation or threshold, electrons hop or tunnel around from one graphene flake to another. So, the as-prepared nanodevices are piezoresistive in nature, and the resistance changes whenever there is a change in distance between graphene flakes. The abovementioned devices were able to detect podiatric pressure, heart, and lung motion (left and right rectus abdominis). The nanocomposite strain possesses high sensitivity, a conductivity of ∼20 S/m (measured by ASTM D4496 - Standard Test Method For D-C Resistance or Conductance of Moderately Conductive Materials), excellent stretchability, and ultra-sensitivity (heart rate was measured 100 BPM). Thus, these graphene-enhanced elastomeric composite (referred to as G-EMC) devices can be an excellent platform for healthcare applications like heart and lung motion detection.
An Investigation of the Influences of Diameter Ratio and Attaching Angle on the Performance of a Helical-Bladed Combined Darrieus-Savonius Wind Turbine
Authors: Saad Ahmed S. , Ahmed Mahmoud 
Published: February 2024

Abstract
Although Darrieus wind turbines are capable of producing high power coefficients, they also exhibit a low self-starting capability. Savonius wind turbines on the other hand are capable of providing relatively high self-starting capabilities but have a lower power coefficient. The objective of the present study is thus to develop a modified design of a combined Darrieus-Savonius wind turbine in order to improve its self-starting capability and power coefficient. The modified combined design consists of helical-bladed Darrieus and Savonius rotors with helical angles of 90 and 45 degrees, respectively. The influences of various diameter ratios in addition to various attaching angles between Darrieus and Savonius rotors in the proposed design are numerically investigated.
The Reynolds-Average Navier-Stokes equations in three dimensions along with the turbulence model of k-ω (SST) are developed and numerically simulated. The predicted results are validated using the available measurements. Thus, numerical predictions of the variations of the coefficient of power versus tip speed ratio as well as the coefficient of torque over a whole cycle can be made. As part of the evaluation of the starting characteristics of the proposed configurations, the static torque coefficient during a complete revolution is also calculated.
Based on the current study, some significant findings can be derived. The coefficient of power remarkably increases with rising the diameter ratio up to an optimal value of 0.45, then a significant reduction in coefficient of power is observed with further increment of diameter ratio beyond 0.45 due to increasing the drag losses by Savonius rotor. In comparison to a solo Darrieus rotor at the same dimensions, the combined turbine with the best design parameters achieved a peak coefficient of power of 0.386 with a performance gain of about 19 %. Furthermore, the combined design significantly reduces the fluctuations of coefficient of static torque in addition to achieving a higher average coefficient of static torque with positive values at all azimuth angles compared to solo Darrieus rotor.
Study of Adhesive Joints Quality Based on Multi-Camera DIC System
Authors: Guo Bicheng , Gao Zhongfang , Gerini-Romagnoli Marco , Yang Lianxiang 
Published: February 2024

Abstract
Carbon and glass fiber-reinforced plastic (CFRP and GFRP) composites have gained popularity in various industries and settings owing to their exceptional strength-to-weight ratio, corrosion resistance, fatigue resistance, and design flexibility. Adhesives are commonly utilized to bond carbon fiber reinforced plastics to other materials or to themselves. Bonded joints have been found to enhance the mechanical characteristics of materials, while also reducing additional costs for practical applications. The bonding region’s strength can be influenced by different material combinations and substrate thicknesses. The present investigation employed a double-sided multi-digital image correlation (DS-Multi-DIC) system to quantify the deformation and fracture mechanisms of adherends during tensile testing. The primary objective was to assess the static impact on the strength of the bonded zone under tensile loading. The system comprises of two stereo vision DIC measurement systems, wherein each system comprises of two GigE cameras. These cameras are positioned at the front and back of the sample, respectively the process of system calibration involves the utilization of the double-sided calibration technique to integrate the coordinate systems of the two DIC measurement subsystems with the global coordinate system. This enables the direct measurement of deformation and strain in three dimensions. This paper examines the impact of adhesive thickness and type on the strength of the bonded area and fracture mechanism by analyzing the alteration in strain distribution and maximum strain during static stretching. The study yielded a conclusion that the magnitude of the bonded region’s strength is positively correlated with the thickness of the bonding material. The cohesive force of the bonded region is positively correlated with the malleability of the adhesive bond. Furthermore, an examination was conducted on the impact of adhesive thickness and type on peeling strain. As the bond’s bending stiffness diminishes, there is a corresponding increase in the peel strain it undergoes. Furthermore, a succinct description is provided regarding the unequal allocation of auditory alterations that occur during stationary stretching.
Physics Based Electrolyte Evaporation Model for Use in Li-Ion Thermal Runaway Simulations
Authors: Poe Dylan , Parhizi Mohammad , Jain Ankur , Kilaz Gozdem , Ostanek Jason 
Published: February 2024

Abstract
Numerical analysis of thermal runaway and propagating failures often relies on solving the transient heat conduction equation. Exothermic decomposition reactions create a heat source within the active material. The generated heat diffuses through the cell via heat conduction and is carried away from the cell via conduction, convection, and radiation. However, many studies neglect the evaporation of liquid electrolyte from the battery cell after the vent mechanism activates despite evidence that evaporation significantly affects the time-to-thermal-runaway. In studies which have considered evaporation of electrolyte, the rate of evaporation was modeled using a semi-empirical relationship instead of rigorous theoretical analysis. This work presents a new, physics-based evaporation model in which the mass transfer of electrolyte in the jellyroll is treated as a 1-D liquid diffusion process. Experiments were conducted to determine the diffusion coefficient of electrolyte through the porous separator material. The 1-D liquid diffusion model was then integrated within an existing battery thermal abuse model. The thermal abuse model with physics-based electrolyte evaporation model was exercised for oven tests at 150 °C and 155 °C and compared with published experimental data. Simulated results agreed well with experimental data, capturing the characteristic temperature drop after vent activation. The model may be used to further investigate the role of electrolyte evaporation on thermal runaway and propagating failures.
Numerical Study on CO2 Hydrate Formation in a Bubble Column Reactor From Flue Gas Mixtures
Authors: Bhati Awan , Kar Aritra , Bahadur Vaibhav 
Published: February 2024

Abstract
Gigascale carbon capture and sequestration (CCS) is increasingly seen as essential to meeting the targets of the Paris Agreement. Sequestration of CO2 as CO2 hydrates (ice-like materials of CO2 and water) has received research attention recently. CO2 hydrates form at medium pressures and temperatures close to freezing from a water-CO2 gas mixture. Bubble column reactors (BCR) are a preferred way of rapidly forming CO2 hydrates. This study uses a recently-developed and validated model to predict performance of a BCR for CO2 hydrate formation from flue gas (CO2/N2). In particular, two performance parameters are analyzed, the gas consumption rate for hydrate formation, and the fraction of CO2 that can be converted to CO2 hydrates (conversion factor). Extensive parametric analysis is conducted to study the influence of pressure, temperature, CO2 mole fraction at inlet, inlet gas flow rate, reactor height and reactor diameter on CO2 hydrate formation rate. Across the range of simulations conducted in this study, the maximum reported hydrate formation rate is 71 ton/yr and the highest conversion efficiency is 67.8%. It is seen that both the performance parameters improve with increasing pressure, decreasing temperature and increasing inlet mole fraction of CO2. Increasing gas flow rate increases the gas consumption rate (i.e., hydrate formation rate) but reduces the conversion factor. This suggests that the operation of BCR for gas separation should involve low flow rates but that high flow rates should be used to synthesize hydrates for CO2 sequestration. An increase in reactor volume by increasing the height or diameter, improves hydrate formation on both performance parameters (rate, conversion factor).