bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mass Transfer Rate Enhancement in Sparged Vessel for Ammonia-Water Nano-Fluid in VARS by Adding Nanoparticles
Authors: Bhujbal Rahul , Nakate Sanjay , Dingare Sunil V. 
Published: February 2021

Abstract
The refrigeration systems are used in domestic and commercial freezing applications. These systems are needed to be used energy efficiently to get the economic operation condition. The vapor compression refrigeration cycle (VCR) is getting replaced by vapor absorption refrigeration system (VARS) as they can use low grade energy. This VARS can be used by making use of waste energy in the form of heat which is readily available for many applications. Performance of the VARS is dependent on the generator and absorber performance. In absorber it is based on the amount of refrigerant absorbed and the solution flow rate. Experimental and Numerical study of bubble absorber and effect of nanoparticle on ammonia water mass transfer is carried out. In this study, different designs for the absorber chamber are viewed and compared together, based on the research did earlier. Looking at the aspects of bubble type absorber designs, these designs give better mass transfer performance as compared to other designs. These designs may be improved to get the energy efficient design of the absorber. Present study includes the enhancement of mass transfer rate by the addition of nanoparticles using aluminum oxide (Al2O3). Here, sparged vessels with NH3-H2O binary fluid are arranged with varying percentage of nanoparticle (Al2O3). This study includes the study of mass transfer enhancements by using nanoparticles. Based on the experimental results carried out for the varying mass flow rates it is found that the mass transfer rate is enhanced significantly, it is because the interfacial area is enhanced by the addition of nanoparticles to the base fluids.
Increased Efficiency in Spontaneously Passing Kidney Stones Using a Novel Ureteral Double-J Stent
Authors: Amiri Manouchehr , Amiri Sorosh 
Published: February 2021

Abstract
Kidney stones are stiff deposit minerals formed in the kidneys. In patients with kidney stones disease, double-J stents are used to increase the openness of the ureter in case of blockage by the kidney stones. The stent surfaces are normally smooth with symmetric friction along the longitudinal axis. In this work, we show that a modified double-J stent with asymmetric friction surface facilitates passage of stone fragments after extracorporeal shock wave lithotripsy or trans ureteral lithoclast. To examine the effect of asymmetric friction on the stone passing efficiency, finite element simulations were conducted. Simulation results revealed that at excitation vibration frequency of 0.15 Hz the stone unidirectionally moves along the stent at an average speed of 0.03 cm/s which is a significant increase compared to the clinical reports. Practically, the asymmetric friction can be made by laser micro-engraving techniques such as the same method in CD writing.
Effect of China Clay on Mechanical Properties of AA7075/B4C Hybrid Composite Fabricated by Powder Metallurgy Techniques
Authors: Pandey Krishna Murari , Manohar Guttikonda , Maity Saikat Ranjan 
Published: February 2021

Abstract
Composite materials are very predominant in the areas of industrial applications, aerospace and defense sectors. Aluminium metal matrix composites are main targeted materials by many researchers because of its low density, high strength, corrosion resistance and economical that makes material suitable for aerospace and automobile sectors. In this work effect of china clay volume fraction on mechanical properties of AA7075/B4C composite was investigated. Effect of china clay volume fraction on mechanical properties was analyzed with the help of results obtained by XRD, tensile, compression and micro hardness tests. From the experimentation analysis and results it was clear that added china clay acts as effective binder material for efficient compaction and ejection of green compacts from the die material after cold compaction processes and gives high strength to the composite material up to 7% volume fraction in sintered composite while in tensile strength after that material strength starts to degrade. In this work critical volume fractions of china clay in AA7075/B4C composite was investigated in tensile, compression and hardness. Further, effect of heat treatment on mechanical properties of the composite material was investigated.
Topology Optimization of the Hip Bone for Walking Using Multi-Load Approach
Authors: Eswara Sai Kumar Kandula , Rakshit Sourav 
Published: February 2021

Abstract
In this work, we use structural topology optimization to design the hip bone with multi-load conditions of walking gait cycle. Previous research works on optimal bone design primarily aimed to design the micro-structure of the femur bone using a multi-load approach with global geometry fixed. To the best of authors’ knowledge, no optimal design research literature is available on the hip bone. This work uses the concept of multiload conditions, since it considers the effect of entire gait cycle while applying loading conditions. We consider three cases for the weights. Those are (i) equi-weight case, (ii) non-equi weight case based on the fraction of the phase in the gait cycle and (iii) non-equi weight case based on the ratio of magnitude of the hip joint force in respective phases to the total hip joint force of the entire walking gait cycle. The optimal designs are compared with natural hip bone by measuring shape similarity using Procrustes Analysis. Results show that the compliance is less for the optimal designs compared with natural hip bone. The shape similarity values for the three cases are found to be 64%, 78% and 73% respectively. Optimal design obtained from the non-equi weight case based on the duration of phase has highest shape similarity value due to creation of a hole similar to obturator foramen in lower portion of the hip bone. The maximum stress and maximum displacement values are lower in optimal designs compared with natural hip bone. From the shape similarity results, the optimal design from the non-equi weight based on duration of the phase may be more suitable for prosthesis applications.
Virtual Fixturing: Inspection of a Non-Rigid Detail Resting on 3-Points to Estimate Free State and Over-Constrained Shapes
Authors: Lindau Björn , Wärmefjord Kristina , Lindkvist Lars , Söderberg Rikard 
Published: February 2021

Abstract
When the geometry of a non-rigid part or pre-assembly is measured fully clamped (over-constrained) in a measurement fixture, the spring-back information and influence from gravity forces are usually lost in the collected data. From the 3D-measurement data, it is hard to understand built in tensions, and the detail’s tendency to bend, twist and warp after release from the measurement fixture. These effects are however important to consider when analyzing each part’s contribution to geometrical deviations after assembly.
In this paper a method is presented, describing how free state shape and over-constrained shape of a measured detail can be virtually estimated starting from acquired data when the part or the preassembly is resting on only 3-points. The objective is to minimize the information loss, to spare measurement resources and to allow for a wider use of the collected data, describing the geometry.
Part stiffnesses, part to part contacts and gravity effects are considered in the proposed method. The method is based on 3D-scanning techniques to acquire the shape of the measured object. Necessary compensations for part stiffnesses and gravity effects are based upon Finite Element Analysis (FEA) and the Method of Influence Coefficients (MIC).
The presented method is applied to an industrial case to demonstrate its potential. The results show that estimated over-constrained shapes show good resemblance with measurements acquired when part is over-constrained in its measurement fixture.
A New and Efficient Meshless Computational Approach for Transient Heat Conduction in Anisotropic Nonhomogeneous Media: Fragile Points Method and Local Variational Iteration Scheme
Authors: Guan Yue , Grujicic Rade , Wang Xuechuan , Dong Leiting , Atluri Satya N. 
Published: February 2021

Abstract
A new and efficient computational approach is presented for analyzing transient heat conduction problems. The Fragile Points Method (FPM) utilized for spatial discretization can, on one hand, like many other meshless methods, be free of the requirement of high-quality meshing, and on the other hand, bypass the difficulty of domain integration problem which is commonly seen in Galerkin meshfree methods. With local, polynomial and discontinuous trial and test functions, the method has a great potential in solving problems with rupture and fragmentation without remeshing. Anisotropy and nonhomogeneity which is challengeable for many spatial numerical methods do not give rise to any difficulties in the present implementation. The Local Variational Iteration Method (LVIM) in the time domain is a highly efficient technology in solving nonlinear problems, in which the time steps can be an order of magnitude larger than the traditional backward Euler scheme and the computing time can be cut by a half. The FPM+LVIM solver is also connected to the prepossessing module of ABAQUS which helps generating the domain partition. It shows the compatibility of the current approach with various partitions and makes it more friendly for engineer users. Several 2D and 3D numerical examples with functionally graded and composite materials are then provided as validations.
Metal Forming With Laser Origami: Parameter Analysis and Optimization
Authors: Ma Peiwen J. , Hao Yue , Lien Jyh-Ming , Peraza Hernandez Edwin A. 
Published: February 2021

Abstract
Laser origami is a metal forming process where an initially planar sheet is transformed into a target three-dimensional (3D) form through cutting and folding operations executed by a laser beam. A key challenge in laser origami is to determine the locations of the cuts and folds required to transform the planar sheet into the 3D target shape. The region of the planar sheet that can be transformed into the target shape through these cuts and folds is denoted as the net. This paper presents a method to determine optimal net(s) for laser origami based on criteria including minimum energy usage, minimum fabrication time, minimum error in the fold angles, and minimum material usage. The 3D target shape is given as a polygonal mesh. To generate a net, each edge in the mesh must be classified as a cut or a fold. The energy, time, and other parameters associated with cutting or folding each edge are determined using experimentally calibrated formulas. A search algorithm is subsequently implemented to find combinations of cut and folded edges that provide an optimal set of nets for the given 3D target shape based on a cost function. Nets that are disconnected or have overlapping regions are discarded since they are invalid for laser origami. The method is demonstrated by applying it to different target shapes and cost functions.
Study of the Cutting Parameters on Surface Roughness and Material Removal Rate in Hard Turning of UHMWPE
Authors: Aguilera-Ojeda César Oswaldo , Saldaña-Robles Alberto , Vidal-Lesso Agustín , Martínez-Ramírez Israel , Aguilera-Gómez Eduardo 
Published: February 2021

Abstract
The surface finish of industrial components has an important role in their performance and lifetime. Therefore, it is crucial to find the cutting parameters that provide the best surface finish. In this work, an experimental study of the effect of cutting parameters on ultra-high molecular weight polyethylene (UHMWPE) by a turning process was carried out. Today, the UHMWPE polymer continues to find applications mainly in the automotive industry and biomechanics because it is resistant to impact and corrosive materials to use. A face-centered Central Composite Design (CCD) and Response Surface Methodology (RSM) were applied to evaluate the influence of the cutting speed (Vc), feed rate (f) and depth of cut (ap) of the turning operation on the Average Surface Roughness (Ra) and Material Removal Rate (MRR). Results allowed obtaining an adjusted multivariable regression model that describes the behavior of the Ra that depends on the cutting parameters in the turning process. The predictive model of Ra showed that it fits well with a correlation coefficient (R2) around 0.9683 to the experimental data for Ra. The ANOVA results for Ra showed that the feed is the most significant factor with a contribution of 42.3 % for the term f 2, while the speed and depth of cut do not affect Ra with contributions of 0.19% and 0.18%, respectively. A reduction of feed from 0.30 to 0.18 mm·rev−1 produces a decrease in surface roughness from 6.68 to 3.81 μm. However, if the feed continued to reduce an increase in surface roughness, a feed of 0.05 mm·rev−1 induces a surface roughness of 14.93 μm. Feeds less than 0.18 mm·rev−1 cause a heat generation during turning that increases the temperature in the process zone, producing surface roughness damage of the UHMWPE polymer. Also, the results for MRR demonstrated that all of the cutting parameters are significant with contributions of 31.4%, 27.4% and 15.4% to feed, speed, and depth of cut, respectively. The desirability function allowed optimizing the cutting parameters (Vc = 250 m·min−1, ap = 1.5 mm y f = 0.27 mm·rev−1) to obtain a minimum surface roughness (Ra = 4.3 μm) with a maximum material removal rate (MMR = 97.1 cm3·min−1). Finally, the predictive model of Ra can be used in the industry to obtain predictions on the experimental range analyzed, reducing the surface roughness and the manufacturing time of UHMWPE cylindrical components.
Scanning Strategies in the PBF Process: A Critical Review
Authors: Malekipour Ehsan , El-Mounayri Hazim 
Published: February 2021

Abstract
The powder-bed fusion (PBF) process is capable of producing near-fully dense metallic parts; however, various defects — particularly thermal abnormalities — can still be observed during the process. Some of these thermal defects — cracks, distortion, delamination of layers, and microporosity — cannot be removed by post-processing operations. The majority of these abnormalities are the result of residual stress, heat accumulation, lack of inter-track /inter-layer bonding, lack of powder fusion, or a combination of these factors. Modifying the scanning strategy (the topology of scanning tracks) can efficiently mitigate these abnormalities by adjusting the process parameters and adopting proper scanning patterns.
The implementation of different scanning strategies significantly changes the ultimate quality of printed parts and manufacturing process lead time. Choosing a proper scanning strategy minimizes the residual stress and internal porosity, generates homogeneous microstructure, and avoids heat accumulation throughout the part during the printing process.
In this work, we conducted a critical review of different scanning strategies, their pros and cons, limitations, and influence on the resulting properties of fabricated parts. Furthermore, we report the latest efforts for improvement of the current scanning strategies and introduce the-state-of-the-art strategies in the multi-laser PBF (ML-PBF) process. The insights provided here can assist scholars in evaluating existing scanning strategies and scanning patterns, and in identifying ways both to overcome scanning limitations and to modify them. On the other hand, it can assist manufacturers in selecting the best scanning strategies for their products based on their designs, demands, and resources.
Control Co-Design for Rotor Blades of Floating Offshore Wind Turbines
Authors: Du Xianping , Burlion Laurent , Bilgen Onur 
Published: February 2021

Abstract
This paper aims to demonstrate the application of control co-design methodology for the rotor blades of a floating offshore wind turbine. A 10 MW reference wind turbine model is utilized in the co-design framework. In this paper, the coupling effect between the system, defined by the pre-cone angle, and the controller, defined by pitch angle, is analyzed with a parametric study. The system parameters of the blade are identified by exciting the system with a step input, and by using the step response. The identified model is used to demonstrate the coupling effects of the structural parameters. The control co-design process is implemented to reduce the blade root bending moment by controlling the pitch angle as a function of the pre-cone angle. Utilizing the 10 MW reference model, the proposed control co-design method can reduce the blade root bending moment and attenuate transverse vibrations faster than the original design. Compared to a sequentially designed controller, the co-design demonstrated reduction of the blade root bending moment with similar attenuation time.
Generating Pseudo-Data to Enhance the Performance of Classification-Based Engineering Design: A Preliminary Investigation
Authors: Du Xianping , Bilgen Onur , Xu Hongyi 
Published: February 2021

Abstract
Machine learning for classification has been used widely in engineering design, for example, feasible domain recognition and hidden pattern discovery. Training an accurate machine learning model requires a large dataset; however, high computational or experimental costs are major issues in obtaining a large dataset for real-world problems. One possible solution is to generate a large pseudo dataset with surrogate models, which is established with a smaller set of real training data. However, it is not well understood whether the pseudo dataset can benefit the classification model by providing more information or deteriorates the machine learning performance due to the prediction errors and uncertainties introduced by the surrogate model. This paper presents a preliminary investigation towards this research question. A classification-and-regressiontree model is employed to recognize the design subspaces to support design decision-making. It is implemented on the geometric design of a vehicle energy-absorbing structure based on finite element simulations. Based on a small set of real-world data obtained by simulations, a surrogate model based on Gaussian process regression is employed to generate pseudo datasets for training. The results showed that the tree-based method could help recognize feasible design domains efficiently. Furthermore, the additional information provided by the surrogate model enhances the accuracy of classification. One important conclusion is that the accuracy of the surrogate model determines the quality of the pseudo dataset and hence, the improvements in the machine learning model.
A Preliminary Study of Combined Heat and Power in a Facility
Authors: Jaladi Divya , Languri Ethan , Cunningham Glenn 
Published: February 2021

Abstract
Rapid economic growth has increased the need for efficient electrical and thermal usage worldwide to not only save in energy but also be competitive in industry. Optimization of the current energy sources ought to be carried out in order to minimize the use of fossil fuels in the coming decades in a manner that is economically feasible. Cogeneration of electricity and heat, also known as combined heat and power (CHP), is one such technique making efficient use of fuel and providing greater power output while making the energy infrastructure of facilities more resilient. This technology is primarily useful in large ind40ustrial or medical centers, as they have a greater proportion of thermal loads than residential or office units. This paper reports a preliminary study at a facility in Tennessee, USA, to determine the cogeneration feasibility and its payback period. This study shows how the calculations are carried out by considering the primary energy consumption costs for determining the modeled payback periods and basic measures to be taken into consideration for a CHP installation at interested facilities.
Enhancing the Steel Tube Manufacturing Process With a Zero Defects Approach
Authors: Sousa João , Ferreira José , Lopes Carlos , Sarraipa João , Silva João 
Published: February 2021

Abstract
The continuous thrive for working safety, customer satisfaction and increasing profits for companies has led to numerous manufacturing and management strategies. One of the most promising strategies nowadays is Zero Defects that focuses on the elimination of defected parts in the manufacturing processes. The benefits of Zero Defect implementation in the manufacturing industry are mainly related to the reduction of scrap material, and everything that does not bring any added value to the product. The result is a reduction of the company’s expenditure for dealing with defective products. In spite the concept not being new, the practical application of such strategies were limited by technological constraints and high investment costs. With the Industry 4.0 evolution, some Zero Defects concepts are more accessible due to the availability of sensors and data related techniques such as Machine Learning and Big Data although a lot of work is still required for component integration to enhance the capability of the heterogeneous technologies.
The quality of the steel tubes is evaluated by sampling and relies on the expertise of the operators for checking for nonconformities. When a defect is detected, the process parameters are adjusted based on prior experience. However, since this is a continuous process, the delay between the appearance of a defect in the process and its awareness leads to a considerable amount of produced scrap material. Worst-case scenario, the defective product can be delivered to the customer damaging the customers trust and leading to additional replacement costs. This paper addresses the application of the Zero Defects approach to the steel tube manufacturing industry. This approach is part of the Zero Defects Manufacturing Platform EU project that is based around a Service Oriented Architecture and microservices approach capable of building, running and managing specific use-case oriented software applications called zApps. The Zero Defects methodology to design a zApp based on key criteria for the steel tube industry is described. Additionally, the envisioned zApps to monitor all the produced steel tube during the manufacturing process are detailed. The inspection systems uses a scanning camera and a laser profile scanner to capture the steel tube defects during manufacturing and prior to packaging. Although the ultimate goal is to eliminate the cause of the defective products, the objective of the zApp is to increase the number of detections of defective products based on industry standards and reduce the amount of generated scrap material.