bluuebunny/crossref_metadata_2025 huggingface dataset:
CFD Analysis of the Combustion of Hydrogen Fuel on a CFM56-3 Combustor
Authors: Domingues Rafael , Brójo Francisco , Oliveira Pedro
Published: February 2023

In the present work is made an overview of the use of hydrogen in aviation, the modifications needed to convert a conventional gas turbine to use hydrogen and a CFD simulation of an existent gas turbine burning hydrogen. The CFD simulation was done in a CFM56-3 combustor burning Jet A (as a reference standard) and hydrogen, with the intention of evaluate the viability of conversion of existent gas turbines to hydrogen, in a combustion point of view, by analyzing the emissions through ICAO’s LTO cycle while burning this fuel. ANSYS Fluent 2020R2 was the software used to perform the numerical study. The RSM was the viscous model used. Only the NOx emissions were assessed as pollutant once the hydrogen combustion products are reduced to water vapor and NOx. These emissions were evaluated through a detailed mechanism and the NOx model available on ANSYS to get a better concordance with the ICAO’s values. During this study, several sensibility studies were carried out for hydrogen burn, for instance, the analysis of the air flow with/without swirl in the primary zone and different inlet pressure and temperature for fuel.
Sustainable Production of Rotationally Symmetrical Components: Approaches to Resource Saving on Tool and Workpiece
Authors: Volke Pascal , Brock Gabriel , Berger Sebastian , Saelzer Jannis , Nickel Jan , Biermann Dirk
Published: February 2023

Sustainability is an increasingly important trend, giving great potential in industrial production to save resources and energy. This paper presents fundamental research results on the reduction of cutting-tool consumption and saving on workpiece-material.

For the basis of a new wear model, explicit knowledge of the thermo-mechanical loads and relative speeds between the tribological partners is of central importance. Therefore, a special open tribometer will be used to parameterize a friction model depending on relative speeds. Both, uncoated and coated tools are used. To reduce experimental effort, numerical simulations serve as an efficient representation of the cutting process. As a novelty in the project’s further course, both the experimentally determined tool temperatures and the friction conditions will be recorded in dependence on the tool wear, complemented by synchronized digitized wear images for validation purposes.

The second work focuses on burnishing as a post-processing method for additively manufactured components. Compared to conventional machining, material and energy is saved and the workpieces’ surface integrity is improved, potentially increasing the components’ lifetime. Experimental tests are extended by finite element simulations, enabling investigations at different scales: At a workpiece model size of several millimeters, residual stresses are to be predicted; at a micrometer range, the surface smoothing is mapped.
Competition Based Learning in Engineering Education
Authors: Chepuri Sai Abhinav , Kowdodi Siva Prasad
Published: February 2023

Mechanical engineering concepts such as Heat Transfer and FEM are better understood by visualizing and getting hands-on experience on the problem where many of the students fail. One such process that helps the students to visualize, understand and feel the concepts is to participate in student-level design and development challenges. There are many organizations spread across the world that conduct student-level design and development challenges. In India, Fraternity of Mechanical & Automotive (FMAE) is a private organization that focuses on student development in the automobile sector by conducting various types of student-level motorsport events like the design and development of Quad Bike, Baja Buggy, Formula Student, etc. Taking part in these competitions creates a platform for the students to form a team, design and develop vehicles, and compete against other teams nationally and internationally. It also increases the student’s ability to work in a team, take responsibility for a mission-driven project, and also increase leadership and managerial skills. During the process, the students enhance their skills of in-depth understanding, visualization, and knowledge of various engineering concepts.
Miniaturized Models in Engineering Education
Authors: Durgesh N. G. S. M. , Kowdodi Siva Prasad
Published: February 2023

Creativity is a vital skill that needs to be possessed by humans, especially during the 21st Century. Understanding heavy machinery like a stacker reclaimer or a complex machine like an engine would be very difficult for a normal student. Today’s education system concentrates mostly on Theoretical education rather than practical education. This type of education is responsible for unemployment and a lack of skilled labor. In competitive exams, more than theoretical knowledge, logical reasoning & cognitive skills are evaluated. Knowledge gained through the application of theory in real-life activities is referred to as practical learning. This method of learning allows students to remember and master a topic for a long time. Exams based on practical learning reveal students’ true intellect, as opposed to marks obtained by rote learning. It is a common misconception that practical learning is only beneficial to technical or management students. This study aims to understand the actual working of mechanisms, as only bookish education is not enough to understand how they work. Understanding the mechanisms through this process made the students interestingly understand the mechanisms and also encouraged them to build other miniature models using their creativity.
Effect of Heat Treatment on the Oxidation and High Temperature Wear Performance of Alloy Ti-6Al-4V Manufactured by Direct Metal Laser Sintering
Authors: Shanmugam Ragavanantham , Veeman Dhinakaran , Shanmugam Mannan Muthu , Kalaiselvan Gopika
Published: February 2023

In this work, alloy Ti-6Al-4V was fabricated using direct metal laser sintering (DMLS) approach and studied the effect of heat treatment (solution treatment 950 °C/2h-furnace cooling and aging 550 °C/6h-air cooling) on the oxidation and wear performance at elevated temperature. The microstructural investigation revealed that as-built alloy consists of a fine-grained martensitic needle shape structure with columnar grains. In the solution treatment aging (STA) treated alloy, the rod-shaped β with different lengths of a was observed. As-built and STA-treated alloy Ti-6Al-4V were subjected to a cyclic oxidation test at 650 °C for 50 h in air. The reaction products developed on the sample’s surface are evaluated by scanning electron microscope (SEM) and X-ray diffraction (XRD). A thick TiO2 layer was formed on the alloy surface, and some cracks were noticed due to thermal stress. The high-temperature wear test was carried out on the Ti-6Al-4V alloy at room temperature (30 °C), 200, and 400 °C using a reciprocating pin-on-disc tribometer in dry conditions. The abrasive wear mechanism was found at RT, whereas oxidation and the adhesive mechanism were noticed at 200 and 400 °C. Results exhibited that STA alloy had a higher wear resistance than that of as-built alloy.
Parametric Analysis of ANFIS, ANFIS-PSO, and ANFIS-GA Models for the Prediction of Aluminum Surface Roughness in End-Milling Operation
Authors: Balonji Serge , Okokpujie Imhade Princess , Tartibu Lagouge
Published: February 2023

Milling is one of the old and common cutting processes that utilize rotating tools to take materials off the main component with a combination of tools and workpiece movements. The texture of a machined surface is a key factor in defining how an essential component interacts with its environment. Trial-and-error machining to produce high-quality surfaces has been a time-consuming method that yields lower production and poor revenue. In this paper, the performances of an Adaptive Network-based Fuzzy Inference System (ANFIS) model has been employed for the prediction of the surface roughness (SR) of a block of Aluminum alloy AI6061 machined on an end-mill CNC machine by varying four input settings namely: The spindle speed of rotation, the tool cutting rate, the radial depth, and the axial depth. The approach consisted of a parametric analysis carried out within each system to obtain the finest models for the prediction. The hybrids ANFIS-PSO and ANFIS-GA have been employed to find out which one, either PSO or GA, optimizes better ANFIS for the prediction of Al6061 SR. Their performances produced better results than the stand-alone ANFIS, with ANFIS-GA yielding the best results of the most negligible RMSE value of 0.01097 and the regression values of 0.9939 for training and 0.8102 for testing.
Investigation of the Mechanical Properties of High-Temperature Polymer (Polyether Ether Ketone-PEEK) With Material Extrusion Additive Manufacturing
Authors: Sarker Md Rashedul H. , Glassmeyer Joseph , Ruble Alexander , Hamidi Youssef K. , Billah Kazi Md Masum
Published: February 2023

Polyether-ether-ketone (PEEK) is one of the high-performance polymers and has versatile applications in different industries. It has higher mechanical strength compared to other high-temperature polymers, and achieving this mechanical strength using additive manufacturing is not straightforward. Additive manufacturing of PEEK requires great attention before, during, and after 3D printing. This study focused on pre-processing and printing parameters to avoid warped samples and achieve high-quality tensile samples. Coating the build plate with high-temperature Nano-polymer glue at different stages has played a significant role in producing high-quality tensile samples and avoiding warped samples. This study also investigates the mechanical properties of 3D printed PEEK with different raster angles (0°, 90°, 45/90°, and +45/−45°) with and without annealed tensile samples. Controlled printing parameters were maintained, including 400 °C extrusion temperature, 160 °C bed temperature, and 90 °C ambient temperature. Higher mechanical strength was found in annealed samples for 0° and 90° raster angles, 97.445 Mpa and 98.4 MPa, respectively.
Assessing Undergraduate Students’ Level of Awareness of Commercialization of Engineering Research Innovation at a Historically Black College and University
Authors: Addo Sampson , Tyagi Pawan , Mutunga Eva
Published: February 2023

Engineering Research Innovation Commercialization (ERIC) seeks to translate products or services from the research laboratory to the marketplace or the end-user for societal benefit. Research indicates that universities have distinctive capabilities that allow them to play an important role in the process of research innovation commercialization. Historically Black Colleges and Universities (HBCUs), though originally established mainly as teaching and blue-collar trade institutions to educate African Americans, have been gradually commercializing several research innovations through patenting. However, this is significantly lower compared to that of their counterparts (specifically, Predominately White Institutions – PWIs). This according to available research is mainly because HBCUs have been traditionally under-served and under-resourced. Currently several programs such as the National Science Foundation (NSF) I-Corps and National Science Foundation Center of Research Excellence in Science and Technology (NSF-CREST) Center for Nanotechnology Research and Education (CNRE)) are being implemented by HBCUs to promote the commercialization of research innovations by training innovators about commercializing innovations. However, little research has been done to assess the level of awareness of engineering undergraduate students at an HBCU about the commercialization of engineering research innovations. This pilot study, therefore, seeks to investigate the level of awareness of engineering undergraduate students at an HBCU about engineering research innovation commercialization. The authors of this study have conducted a similar study that focused only on engineering graduate students in an HBCU. To achieve the purpose of this study, we developed a survey that adopts both binary and ordinal scales of question and administered it to 30 engineering undergraduate students in an ABET-accredited HBCU. After collation and analysis, the results indicate a low level of awareness of engineering research innovation commercialization by engineering undergraduate students at this University. Though at a pilot stage (to be validated by a larger study in different HBCUs), the study recommends that HBCUs initiate new or strengthen ongoing innovation commercialization training programs by including it in undergraduate engineering first-year courses such as “Introduction to Engineering” and related courses to help students become more aware of the opportunities in engineering research innovation commercialization processes.
The Use of Low-Code During a Skill Shortage
Authors: Büscher Aaron , Schilberg Daniel , Wiegert Lars
Published: February 2023

With rising requirements for digitalization, corporations must increase the speed in which their production and products are digitized. Because of that, there is an increasing demand of software developers which has led to a high skill shortage in Germany. Combined with rising expectations for speed and costs to develop a platform, this led to a problem, that needs to be solved.

The goal of this paper is to estimate the benefit of using Low-Code platforms instead of traditional programming languages. Therefore, the elaboration deals with the central research question whether a Low-Code platform can support corporations through the skill shortage and at the same time reduce time and costs that it takes to develop an application.

To answer this question, a Value Benefit Analysis was used to specify which platform provides the highest benefit for a use-case in the production of Vitesco Technologies in Dortmund. Thereupon, an example application was built to determine the usability.

As final result, it can be concluded that the usage of Low-Code platforms in average leads to less time and costs that is needed for the development. In addition, these platforms are easy to use even without prior knowledge which leads to an advantage that can be used during a skill shortage. On the other hand, it also results in less flexibility which makes it harder to program complex functionalities.

This demonstrates that a Low-Code platform can provide a great benefit when used for simple applications, whereas it is not useful for the use of more complex applications.
Utilizing Bilayer Shrinkage to Assemble Complex Ceramic Shapes
Authors: Hartwell Alexander R. , Slabaugh Nathaniel , Ahn Jeongmin
Published: February 2023

The art and engineering worlds have exemplified the power of ceramic materials in seemingly limitless applications for millennia. Despite these achievements, limitations have been pervasive with regards to obtainable final geometries. To continue to expand the repertoire of achievable ceramic forms, a variety of advanced manufacturing techniques have been explored. One method, increasingly common within the world of soft matter, is self-assembly. By utilizing deformation behaviors of materials through swelling, shrinking, stiffening, relaxing, etc. materials can form themselves into seemingly unimaginable shapes. Though it is less intuitive to apply this idea to the seemingly rigid medium of ceramics, this work shows it is possible by utilizing bilayer shrinkage. Through a combination of computational simulation and experiment, predictions for curvature as well as the final shape of the ceramic composite are made. Unexpected behaviors at the macroscale and microscale are discussed as targets for future investigation. Both within the fundamental world of material behavior as well as in the realm of engineering application, this method shows tremendous potential.
Intelligent Modelling and Machining Characteristics of Hybrid Machining for Hybrid Metal Matrix Composites
Authors: Reddy Janvita , Yadav Ram Singar
Published: February 2023

With the invention of advanced engineering materials, the shaping of such materials became a challenging issue. Two or more reinforcements are added to the metal matrix and form hybrid metal matrix composites (HMMCs) with preferable material properties, but shaping became quite challenging. Hybrid Surface grinding Electrical Discharge Diamond Face Surface Grinding (EDDFSG) is a suitable hybrid machining process capable of machining complicated HMMCs. With the help of EDDFSG, adverse effects of both traditional and non-traditional techniques are overcome while combining their benefits for a better machining results. A hybrid composite machined with a hybrid machining process requires an advanced technique for modeling and the performance prediction of complex machining characteristics. Material removal rate (MRR) and (Ra) rely on the process parameters, their influence must be extensively studied. Machine learning, a subset of Artificial Intelligence, allows machines to learn, develop, and execute tasks like human beings based on data rather than explicitly programmed. In the present work, an attempt has been made to develop a Machine Learning (ML), K Nearest Neighbor (KNN) based model, to predict MRR and Ra for machining EDDFSG of Al/Al2O3p/B4Cp and Al/SiCp/B4Cp HMMCs. The KNN algorithm is one of the efficient ML models for regression. Our training data set is normalized using the Min-max scalar to avoid a biased algorithm towards one process parameter. The model’s accuracy is validated by average standard error metrics on the test data set. The impacts of the process parameters like pulse-on time, gap current, wheel speed, pulse-off time, grit number, table speed over the response variables of the ML model is studied and analyzed in depth. The remarkable results are found pertaining to machining characteristics of the EDDFSG process over traditional modelling techniques.
Experimental Characterization of Critical Heat Flux and Minimum Film Boiling Heat Flux for Additively Manufactured Cooling Channels for Liquid Nitrogen Saturated Flow Boiling
Authors: Ortega Debra J. , Amador Alejandro , Choudhuri Ahsan R. , Rahman Md Mahamudur
Published: February 2023

This work experimentally characterizes the critical heat flux (CHF) and minimum film boiling heat flux (MFBHF) in additively manufactured cooling channels for regeneratively-cooled rocket engines during high pressure saturated internal forced convective boiling of liquid nitrogen (LN2). Three different channels with hydraulic diameters of 1.8 mm, 2.3 mm and 2.5 mm were fabricated by the National Aeronautics and Space Administration (NASA) Marshall Space Flight Center (MSFC). The channels were fabricated using Powder Bed Fusion (PBF) advanced 3D printing of the rocket engine material, GR-Cop42, a copper-chrome-niobium alloy. The fabricated channels were tested using a custom-built cryogenic High Heat Flux Test Facility capable of operating up to 4 MPa of pressure and 10 MW/m2 of heat flux. The channels were asymmetrically heated from the bottom to simulate the performance of the cooling channels of a rocket engine. The high-pressure flow boiling tests were performed at 1.38 MPa with respective saturation temperature of 109 K using LN2 as the working fluid in horizontal orientation of the channels. The volumetric flowrate of LN2 is held approximately constant at 47 cm3/s for all channels. The experiments were performed beyond the CHF to ensure film boiling inside the channels, and then gradually decreased the given power until MFBHF was reached. A CHF of 543 kW/m2 and a MFBHF heat flux of 486 kW/m2 were achieved for the 1.8 mm hydraulic diameter channel. Furthermore, the experimentally measured CHF values were compared with the correlations available in literature. More than 84% increase in CHF has been experimentally measured for the additively manufactured rough cooling channels as compared to the CHF prediction based on literature correlation for smooth channels.
Hydrophobicity Improvements of Polymers Used in Biomedical Applications
Authors: Hossain Mohammad Motaher , Lokasani Vinay Reddy
Published: February 2023

Improvement in hydrophobicity is important for polymers used in various applications such as biomedical applications, as it can delay their degradation due to long-term exposure to moisture environments. Although a number of surface modification techniques have been developed over the years to improve hydrophobicity, their specific influences on hydrophobicity enhancement as well as long-term mechanical and tribological performances are yet to be fully understood. In this study, surface textures, with variation in type and geometry, are introduced on Ultrahigh Molecular Weight Polyethylene (UHMWPE) and High Density Polyethylene (HDPE) surfaces to study the effect of surface modification on hydrophobicity and long-term mechanical and tribological performances. Based on the theoretical study using Wenzel and Cassie-Baxter models, surface textures of various types and dimension are introduced on UHMWPE and HDPE surfaces. The results show that introduction of surface textures significantly improves the hydrophobicity of polymers. Specific relationship between texture type and geometry, and improvement in hydrophobicity is explored. Based on the comparison between experimental results and theoretical models, transition state modeling seems to be more suitable in describing the change in hydrophobicity with the addition of surface texture. The study provides useful guidelines to improve hydrophobicity of polymers for biomedical applications.
Investigating the Thermal and Mechanical Properties of Polyurethane Urea Nanocomposites for Subsea Applications
Authors: Okolo Chinyere , Elmarakbi Ahmed , Birkett Martin
Published: February 2023

Commercial applications of polymer nanocomposites for materials used in offshore settings is continuously touted as a potential solution to expand the material property envelope of polymers used in high pressure and temperature environments. In this regard, polyurethane urea (PUU) has been successfully used in such environments, however, they are limited in terms of their ability to offer multifunctional behavior i.e., thermal conductive behavior with mechanical properties. This gap offers the opportunity for their properties to be enhanced as an advanced multi-functional polymer.

Hence, in this study, polyurethane urea/graphene nanocomposites were synthesized using commercial Polyurethane urea (Task 12), and graphene nanoplatelets (GnP). The graphene nanoplatelets were dispersed in one part of the polyurethane urea component using facile dispersion methods. The properties of the new PUU nanocomposite materials were studied using SEM, mechanical and thermal analysis techniques (DMA and Hot Disk), to examine the development of the multifunctional properties in the PUU nanocomposite. Our analysis describes the influence of graphene nanoplatelets at ultra-low concentrations on multi-functional properties of the PUU nanocomposites. The developed nanocomposites recorded a 16% increase in the tensile strength and an 8% increase in the thermal conductive values. The property improvements are credited generally to the high aspect ratio of graphene nanoplatelets, dispersion and filler-polyurethane interactions at the interface. The impartation of multi-functional behavior, in enhancing the thermal conductivity whilst maintaining the mechanical properties makes it a potentially valuable for subsea applications.
Integration of Hybrid Porous Casting in Solar Receivers to Increase Solar Systems Efficiency
Authors: Gören Sara , Barbosa Flavia , Constantino Erany , Puga Hélder , Teixeira José
Published: February 2023

Concentrated solar thermal (CST) technologies have been considered a promising solution to achieve carbon neutrality by 2050. However, to make CST systems attractive to the international energy sector, their efficiency must be enhanced and low-cost manufacturing processes should be used. In this context, an innovative solar receiver for parabolic-dish solar concentrators is developed in this work, focusing on the improvement of the absorption capacity and heat transfer to the thermal fluid. To enhance solar radiation absorption, a pyramid-shaped texture surface is constructed. In addition, the multiple jet impingement process combined with porous media is applied to ensure high heat transfer rates to the thermal fluid. To evaluate the system efficiency, an experimental setup is developed using a parabolic reflector with a solar tracking system and the flow dynamics of multiple jets impinging on the porous surface is analyzed using Particle Image Velocimetry (PIV). The results show that the tested absorber surface increases the solar absorption efficiency by 6.5 %, compared to the smooth surface. Furthermore, the jet’s flow dynamics and heat transfer analysis shows that the porous surface combined with the air jets increases the heat transfer rate, obtaining optimal values for jets velocities ranging between 5 and 10 ms−1.
Experimental Investigation on the Use of Vibration Signals Combined With Supervised Classification to Predict Radial Load Condition in Roller Element Bearings
Authors: Abu-Mahfouz Issam , Banerjee Amit , Rahman Esfakur
Published: February 2023

In this work, vibration response of a rolling element bearing under the influence of static radial loading is investigated. Radial loading results in a periodically varying stiffness (or compliance) which causes a cyclic dynamic response of the bearing assembly even under perfect balancing and other operating load conditions. These loads cause high stresses to develop in bearing elements and may cause fatigue, cracks, and spalls that limits the life of these components. A special bearing test rig was designed and manufactured to apply varying levels of radial load and measure the vibration response of the loaded roller bearing. The test is focused on new bearings free from any faults or defects. The radial load is varied in steps and the vibration signal is collected and analyzed at each level for different rotor speeds. The spectral components are analyzed using Fast Fourier Transform (FFT) and time-frequency wavelet transform. Statistical techniques are applied to both the vibration signature obtained using a piezoelectric accelerometer sensor and the wavelet decomposed approximations and details of the original vibration signals. The statistical measures, wavelet approximation and details are first processed for feature set reduction since many of the features are highly correlated. This is done using three feature reduction and subset selection methods — ReliefF, Recursive Feature Extraction (RFE) and Multi-Cluster Feature Selection (MCFS). These features and the original extracted features are used as features to train two classifiers. The classification is used to estimate high and low thresholds for both radial load and running speed. The classifiers used are (1) radial-basis function support vector machine (RBF-SVM), and (2) k-nearest neighbor (kNN). Performance of machine learning algorithms depends on the training data and physical collected datasets are often limited to specific operating conditions, necessitating the use of training with many models using multi-fold cross-validated subsets. In this study we have used ten models using two-fold cross validation for training and validation. The classification results reported are average of these models. In limited experimentation, the RBF-SVM outperforms the kNN classifier and among the feature sets used, the ReliefF set seems marginally superior to the other sets. However, the accuracy, precision, and recall (combined as an F-score) of the original extracted feature set are better than the reduced feature sets; the downside being the relatively high run time in the training phase.
Investigation of the Dimensional Accuracy of Additively Manufactured High-Temperature Material (PEEK)
Authors: Atatreh Saleh , Alyammahi Mozah Saeed , Susantyoko Rahmat Agung , Mohammed Abdallah
Published: February 2023

Additive Manufacturing (AM) of spare parts is a compelling production route with various benefits to the industry in terms of cost, lead time, and quality. Multiple research studies have highlighted the positive impact of high-performance manufacturing polymers such as Polyether Ether Ketone (PEEK) using Fused Filament Fabrication (FFF) technology in industrial and medical applications. With regards to the dimensional accuracy of the end products after 3D printing and associated thermal post-processing, there is a need for a systematic approach to quantitative evaluation. In this research study, we proposed a new benchmarked design of a test part along with a design of an experiment to evaluate the dimensional accuracy of PEEK parts in spare parts applications. The results revealed a fair dimensional accuracy with a deviation less than 1.6% of the original design. Furthermore, we found no significant effect of annealing on the dimensional accuracy of the PEEK 3D printed parts.
Simulation for Optimization of a Filter Cake System
Authors: Johnson Alyssa , LeBleu Allison , Zhang Ning
Published: February 2023

The purpose of this project is to create a computational fluid dynamics (CFD) simulation of the cake filtration process for Agrilectric Research. Cake filtration is the process by which solid particulate is filtered out of a mixture of fluid and solid phases. As the mixture flows through the system, the particulate accumulates on a filter cloth to form a filter cake, which acts as an added filtering medium to the system. The results obtained from this project can be used to aid Agrilectric in the development of their experimental testing methods by providing the ability to measure and predict filtration properties and to experiment with different filter cake designs to improve filtration methods and performance, without reliance on empirical data.

The work was completed using the Workbench platform with the Fluent solver from the Ansys Student software bundle. A 20 cm long, 10 cm diameter filter cell was modeled and meshed through Workbench and was imported into Fluent to conduct the simulation. The flow of a mixture of water and a particulate phase of rice hull ash (RHA) was simulated using the Eulerian multiphase model. This would show the movement of the RHA through the system and the accumulation of the particulate on a filter cloth over time. The filter cloth was modeled using a porous cell zone to mimic filtering properties.

The simulated solution shows RHA flowing into the system and initially passing through the filter cloth. After some time, a packed layer of particulate forms across the width of the filter cloth that allows a filter cake to accumulate in the system.

The results from the multiphase simulation prove that with more research and simulation development, the model can be improved to represent a realistic cake filtration system which can be used to supplement or to replace existing laboratory testing.
Experimental and Statistical Optimization of Carbon-Fiber Reinforced Nylon Composite Based 3D Printed Cellular Structures
Authors: Hisham Ahmad , Ali Shafahat , Abdallah Said , Mohammed Abdallah Nassir Abdo , Susantyoko Rahmat Agung , Pervaiz Salman
Published: February 2023

The development of advanced composite materials in the recent years has changed numerous aspects of the manufacturing sector. These advanced composite materials showed the potential to replace high-performance alloys at extremely competitive costs. Additive manufacturing gained popularity in the industry due to the ability to print complex shapes. As per existing literature cellular geometry has a controlling influence on the mechanical behavior, and it can be employed to have tunable mechanical properties. Onyx™ is a composite material comprised of nylon mixed with chopped micro-carbon-fiber. For this study, 3D printed nylon-carbon fiber reinforced composite specimens were fabricated using a high-end Markforged® X7™ printer. The study aimed to experimentally investigate the Young’s modulus, ultimate tensile strength, and toughness of the 3D printed nylon-carbon fiber composites having cellular geometry structure. The study investigated different cellular geometry patterns, strain rates and layer heights. Taguchi assisted design of experiment was utilized. To reach reasonable conclusion, a multi objective optimization technique known as grey relational analysis was utilized. Parameters should be optimized in to have proper melting of filament and material solidification. It was found that the optimal parametric condition was diamond horizontal infill pattern, strain rate of 1 mm/ min and a layer height of 0.1 mm. It was observed that sensitivity of 3D printed cellular materials significantly controls the quality of the specimens.
Optimized HVAC Air Distribution for Improved Air Quality Using CFD Analysis
Authors: Kokash Hussein , Burzo Mihai G. , Agbaglah Gbemeho , Mazumder Fardeen
Published: February 2023

The energy consumption of Heating Ventilation and Air Conditioning (HVAC) systems accounts for a large proportion of global energy usage so even a small percentage of energy savings in these systems will account for important absolute value savings. One such saving can be realized by better designs as well as optimizing existing air distribution system. The indoor air quality (IAQ) is also greatly impacted by the air distribution system. In this work, the task of optimizing both the placement and the design of diffusers is investigated so acceptable Air Changes per Hour (ACH) numbers are attained with less energy consumption and good thermal comfort. The ANSYS Fluent software was used to optimize the design and placement of a newly developed diffuser. The proposed air distribution system is design to produce conditions like what one would experience while standing outside in a small breeze while experiencing perfect weather (room temperature, uniform air temperature distribution, air speed less than 2 m/s) [1]). This work is an extension of a previous study where a new diffuser design was proposed, which takes advantage of the Coanda effect [2]. The numerical analysis includes realistic models of a 9 × 9 × 3 m (width × length × height) classroom, which is occupied by students and a teacher. To be more realistic, it includes furniture, a door and windows. The simulated Heating Ventilation and Air Conditioning (HVAC) system complies with ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) standards for acceptable air quality. This investigation proposes a template on how anyone can optimize the location and placement of the air diffusers while achieving both thermal comfort and good IAQ. While this work was inspired by the COVID-19 pandemic this is foreseen to be an important ongoing issue and could lead to future advances in HAVC system that improve IAQ and produce better thermal comfort with improved energy savings.
Derivation of the Exact Curvature Formulation for Gothic Arch Ball Screw Grooves
Authors: Bertolino Antonio C. , De Martin Andrea , Mauro Stefano , Sorli Massimo
Published: February 2023

No exact formulations are present in literature to calculate the principal curvatures of the ball screw grooves, while approximate equations are commonly adopted due to their simplicity. However, they derive from the ball bearing theory and do not take into account ball screw’s characteristic main geometric parameters, such as the helix angle. This leads to approximation relative errors up to 50% for commercial off-the-shelf ball screws. In this paper a new exact explicit exact solution is proposed by means of a rigorous mathematical approach. The helix angle and a generic gothic arch shape of the raceway profile are taken into account. The results of the exact and literature formulations are presented and compared. The principal curvature is seen to be strongly dependent on the helix angle and, therefore, the proposed exact solution should be used in the design phase and, in general, when high accuracy is required, such as in high-fidelity models for prognostic activities.
Trajectory Tracking in the Image Frame for Autonomous Navigation of UAV in UAV-AGV Multi-Agent System
Authors: Sivarathri Ashok Kumar , Shukla Amit , Gupta Ayush , Kumar Amit
Published: February 2023

UAV-AGV heterogeneous multi-agent robotic system has drawn the attention of researchers to explore its capabilities in different perspectives. The UAV-AGV can concatenate their individual capabilities to overcome the drawbacks of each. UAV will benefit in payload and AGV will have the navigation guidance due to the presence of UAV. Collaborative kinematics between both agents is basic requirement of the system. Vision-based method is one of the techniques to implement collaborative motion. A high-level sliding mode controller is developed and validated for the vision-based navigation of UAV for reaching the target/AGV. Gazebo simulations are performed for trajectory tracking in the image frame to reach the target by the UAV. UAV autonomously detects the target and plans the trajectory to reach it. Apparent size-based depth controller is developed for the UAV and simulated in the Gazebo. Altitude trajectory tracking is implemented for the UAV using sliding model controller. Sliding mode based high-level controllers are performing well for the navigation of UAV and trajectory tracking in the image frame opens a different approach for the reaching of AGV by UAV. A non-linear depth controller is developed and simulated in Gazebo which can be useful for the landing task of UAV over AGV.
A Time-Dependent Two Species Explicit Finite Difference Computational Model for Analyzing Diffusion in a Drug Eluting Stented Coronary Artery Wall: a Phase I Study
Authors: Edwards Maegan , Kizito John P. , Hewlin Rodward L.
Published: February 2023

This paper outlines results for a mathematical drug transport model developed for simulating the transport of a hydrophobic drug in a drug eluting stented coronary arterial vessel wall. The mathematical drug transport model incorporates the diffusion equation with a two species (free and bound drug) reversible equilibrium reaction source term to account for tissue binding. The model is solved by an explicit 2-D finite difference method for discretizing and solving the free and bound convection equations with anisotropic vascular drug diffusivities. The relative reaction rates control the interconversion of drug between the free and bound states. Results include provide a glance at the relative distribution of the two drug forms in a two-dimensional model of the arterial vessel wall. The model also reveals how a single species drug delivery model cannot accurately predict the distribution of bound drug.
Aerial Vehicle Rapid 3D Map Generation for Safe Landing Area Detection
Authors: Tatoglu Akin , Chun Yin Cheng , Cervello Brianna , Corrado Antonio , Balko Bernard , Sohn Kiwon
Published: February 2023

This project assists in building a robust control LiDAR scanning unit that helps aerial vehicles land autonomously. The LiDAR scans the terrain, detects static or dynamic obstacles, and helps target safe landing areas. The whole terrain scanning system uses a robust control system to control the LiDAR position to collect point clouds around the environment and use ICP (Iterative Closest Point) to create a 3D point cloud map. In the robust control system, IMU (Inertial Measurement Unit) is used to control the servo to ensure the control system had an accurate target angle for the LiDAR scanning. MSAC algorithm is used in the 3D mapping to help the system detect flat areas for an aerial vehicle to land. This project also shows the different voxelization levels (1 × 1 and 5 × 5) of the flat surfaces and the maximum point to plane distance changed (0.05, 0.25, 1, and 10). Also, an exaggerated voxelization level (10 × 10) was investigated to get a rapid first-level estimation of flat surfaces. The results of the different values and comparisons are also noted and shared. This study is the variable resolution mapping and perception portion of our full-scale heterogeneous localization and mapping research project of Autonomous Mobile Robotics Research Group.
Separating Oil-Water Mixtures Using Bump Arrays
Authors: Bamberger Judith Ann , Pease Leonard F. , Burns Carolyn A. , Minette Michael J.
Published: February 2023

Particle separation is an important process step across many fields. One technique being applied for separating solids such as blood components or sand particles from carrier fluids is the use of arrays of aligned posts called deterministic lateral arrays to bump particles to one side in the flow stream to induce separation. This technique may be useful for separation of deformable particles including oil droplets.

The ability to efficiently separate two-phase industrial (oil/water) mixtures is key for future use of valuable resources. The ability to reclaim petroleum production water may be critical for the Central High Plains (Colorado, Kansas, New Mexico, Oklahoma, and Texas). Current drawdown trends in the High Plains alone suggest loss of up to 40% of the aquifer area by 2100 that will cause the switch from irrigated to dryland farming. Proving this technology is key to reuse of petroleum production water for crop irrigation or to replace water from currently failing aquifers in rich agricultural lands of the Central High Plains.

We conducted experiments applying mesofluidic separation for flowing two-phase (oil/water) mixtures. Experiments were conducted using oil with water as the carrier fluid; separation was achieved over a range of oil-water concentrations. We describe the results of these experiments in this paper.
Multichannel Electromechanical Impedance Structural Diagnostics in Plate Specimens
Authors: Nwokocha Funmilola , Zagrai Andrei , Hunter David
Published: February 2023

Structural health monitoring has become increasingly important in order to save costs and improve the safety of structures. One of the methods of monitoring the health of structures is the use of thin piezoelectric wafer active sensors to measure the electromechanical impedance of the integrated structure/sensor system. These wafers have proved to be efficient in structural diagnostics as they serve as both actuator and sensor for the structures they are attached to. In this contribution, a multichannel unit, which is an arrangement of single miniaturized electro-mechanical impedance units, is utilized to measure the electromechanical impedance of a complex plate structure. The multi-channel unit was validated by measuring the impedance signature of a cantilevered beam and comparing the results with those obtained using a desktop impedance analyzer, the HP4192A.

A numerical modelling of 2D structures was performed using finite element analysis on COMSOL multiphysics software. This was validated by comparing the electromechanical impedance data obtained from the numerical modelling with analytical and experimental data. The specimen was numerically modelled for each sensor bonded to its surface and the results were analyzed. Furthermore, all the sensors on the specimen were simultaneously excited within the same frequency band and the electromechanical impedance data from each sensor was compared with those from same sensor when only one sensor was excited. The results were analyzed and discussed. A numerical modelling of the specimen with all the sensors simultaneously excited was also carried out and the results were compared with experimental data.

The multi-channel unit was also used for damage detection in plate specimens. Structural damage was introduced in the specimen and the electromechanical impedance signatures of the damaged specimen was measured. The result was analyzed and compared with results obtained from the pristine specimen in the same frequency band. The data from each sensor was analyzed and discussed. The efficiency of piezoelectric sensors for detecting damages in structures was highlighted and the effect of sensor location on the accuracy of detecting damages in structures was presented. This suggests optimum sensor location for damage detection in structures.

Finally, the multichannel unit was used to measure damage detection in the specimen at different frequencies when excited simultaneously by all sensors. The electromechanical impedance data obtained was analyzed and compared with data from the pristine specimen and in the single frequency band. The ability of piezoelectric sensor to detect damages in simultaneously varying frequency bands was explored. Recommendations for the application of the multichannel electro-mechanical impedance approach in structural health monitoring were given.
Heat Transfer Characteristics of Particle Flow Through Additively Manufactured (SS 316L) Lattice Frame Material Based on Octet-Shape Topology
Authors: Aider Youssef , Mishra Ashreet , Li Like , Cho Heejin , Singh Prashant
Published: February 2023

This paper presents experimentally obtained heat transfer characteristics of additively manufactured lattice frame material based on Octet-shaped unit cell. Binder jetting technology was used to print lattices in Stainless Steel 316L material. Lattice porosities ranging from 0.75 to 0.9 were investigated where thermal transport characteristics were obtained for void space occupied by air and particles. Particle diameters were varied from 266–966 microns. Effective thermal conductivity and averaged heat transfer coefficient was calculated through steady-state experiments. It was found that presence of lattice enhances the effective thermal conductivity by 2–4 times when compared to packed bed of particles alone. Furthermore, for gravity-assisted particle flow through lattice panel, significantly high convective heat transfer coefficients ranging from 200–400 W/m2K were obtained for the range of particle diameters tested. The superior thermal transport properties of Octet-shape based lattice frame material for particle flow through them makes it a very promising candidate for particle-to-supercritical carbon dioxide (sCO2) heat exchanger in concentrating solar power (CSP) application.