Hydraulic Concepts Research Articles

Peripheral blood to next-generation sequencing ready DNA library: a novel engineering design for automation

Whole genome sequencing (WGS) has become a gold standard for diagnosing genomic variation. Peripheral blood is a common sample source for the extraction of nucleic acids for Next-Generation Sequencing (NGS) applications. Here, we present an integrated and fully automated device design that uses new concepts of fluid mechanics, heat-mass transfer, and thermodynamics of enzymatic reactions to extract nucleic acids from the blood and perform DNA library preparation from a pre-filled plate. We demonstrate that the presented device effectively extracts dsDNA with an average of 25.03 µg/mL and 25.91 µg/mL yield from citrate-stabilized human peripheral blood stored in Fresh (4 °C) and Frozen (-20 °C) conditions, respectively. Furthermore, our method automatically extracts nucleic acids and creates a high-quality sequence-ready DNA library from blood stabilized with citrate and EDTA for 8 samples simultaneously in a single run with a total operation time of ~ 7 h. Our results show the required coverage and depth of the genome, highlighting an essential application of this device in processing blood samples for genome sequencing.Graphical

Dynamic characteristic analysis and key parameter optimization of throttling orifice type air damping air spring

Abstract The unique hysteretic characteristic of rubber bellows and the nonlinear flow of internal airflow in the system results in the significant nonlinear dynamic characteristic of throttling orifice type air damping air springs (OADASs). To solve the problem of mathematical representation of dynamic characteristic and key parameters optimization of throttling OADAS, this paper comprehensively considers the hysteretic characteristic of rubber bellows under variable pressure, the nonlinear dynamic characteristic model and linear model of throttling OADAS are established based on the concepts of gas thermodynamics and fluid mechanics. The static and dynamic characteristic tests of the throttling OADAS are conducted, to verify the accuracy and effectiveness of the proposed model, and to reveal the influence laws of excitation amplitude, excitation frequency, and throttling orifice diameter on the quantitative characterization indexes. Finally, a complete throttling orifice diameter optimization method is proposed based on the eight-degree-of-freedom model of the entire vehicle. Optimization results illustrate that the RMS values of the vertical acceleration of the body and the vertical acceleration of the driver are decreased by 19.02% and 38.44%, respectively. Overall, the outcomes of this paper can provide the design idea and theoretical basis for air damping matching and active suspension control.

EXERGOECONOMIC ANALYSIS OF A HYBRID SYSTEM OF WASTE INCINERATION AND ABSORPTION REFRIGERATION

The current global scenario presents a significant increase in energy demand for HVAC-R (Heating, Ventilation, Air Conditioning and Refrigeration) systems. Considering also that Brazil has the sixth most expensive energy in the world and that there is currently a greater scarcity of natural resources for energy generation, it is necessary to seek viable alternatives with lower energy consumption to the currently most used models, without any quality loss. On the other hand, absorption refrigeration and waste incineration systems can be lines of studies and research to be considered, considering that it is possible to reduce electrical energy consumption and also the environmental impacts that the usual compression refrigeration systems provide. . . In this context, one of the segments of Thermal Systems Engineering studied is the exergoeconomic analysis that comprises the concepts of Heat Transfer, Fluid Mechanics and Thermodynamics, based on the Second Law of Thermodynamics and which uses the notions of optimization and economic analysis. Therefore, this work aims to perform an exergoeconomic analysis of a hybrid system of waste incineration and absorption refrigeration, with the specific objective of developing an exergoeconomic model for the hybrid system. Absorption incinerator-refrigerator. This is an exploratory bibliographic research using an absorption refrigerator from the Center for Research and Development of Self-Sustainable Energy (NPDEAS) of the Federal University of Paraná, in which a model was made with a macroscopic approach of the mass and heat transfer phenomena of a absorption refrigeration cycle, applying the principles of conservation of mass and energy in steady state for each component of the cycle, that is, each component will be considered as a single control volume. It is expected that it will be possible to predict the behavior of the absorption refrigeration system and that it will be possible to develop a scientific analysis tool to design, control and optimize absorption refrigeration systems, using waste incineration. The highest exergy destroyed was verified in the desorber with about 0.9461 kW and through the exergoeconomic analysis of the incinerator, it was found that the cost rate associated with the product of the incineration gases was $ 39,926.31 per year.

Online physics laboratory course: United Kingdom Professional Standards Framework perspective from Walailak University, Thailand

This paper describes a case study of an online physics laboratory course implemented for 254 engineering students at Walailak University in Thailand in response to the COVID-19 pandemic. The laboratory sequence was designed based on the United Kingdom Professional Standards Framework and covered eight experiments on fundamental concepts of motion, electricity, waves, and fluid mechanics. The experiments were conducted at students' homes using physics education technology simulations, Tracker for video analysis, smartphones, and home-based apparatuses. During the experiments, students shared their progress with classmates and lecturers through screen sharing, which facilitated exchanges of ideas and difficulties. The paper discusses the successful implementation of the online laboratory course and the challenges encountered, such as student engagement, resource limitations, and practical skill development. The insights gained from this case study may be useful for online laboratory education beyond the pandemic.

Numerical investigation of the influence of the nozzle bump on nozzle flow

Fluid Mechanics is the study of liquid or gas performance in motion or at rest. Many of the engineering disciplines apply fluid mechanics principles and concepts. With the development of technology, computer is involved in the field, which leads to computational fluid dynamics. In this paper, nozzles with various shapes of bump are used as the research object to investigate the influence of the bump on the nozzle flow via small disturbance approximation. Specifically, triangular, parabolic, irregular and combined shapes are utilized. Two different situations are also included in this paper, which are subsonic and supersonic case. The experimental results demonstrated that within reasonable parameters as the variable increases, the change becomes clearer. When area decreases in the same shape, the streamlines become fluctuant more extremely, especially the one near the boundary. The assumption that the fluid flows disorderly near the bottom is also verified by the simulation.

Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical Transactions paper: part 2.

In 1923, the Philosophical Transactions published G. I. Taylor's seminal paper on the stability of what we now call Taylor-Couette flow. In the century since the paper was published, Taylor's ground-breaking linear stability analysis of fluid flow between two rotating cylinders has had an enormous impact on the field of fluid mechanics. The paper's influence has extended to general rotating flows, geophysical flows and astrophysical flows, not to mention its significance in firmly establishing several foundational concepts in fluid mechanics that are now broadly accepted. This two-part issue includes review articles and research articles spanning a broad range of contemporary research areas, all rooted in Taylor's landmark paper. This article is part of the theme issue 'Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical Transactions paper (Part 2)'.

Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical Transactions paper: part 1.

In 1923, the Philosophical Transactions published G. I. Taylor's seminal paper on the stability of what we now call Taylor-Couette flow. In the century since the paper was published, Taylor's ground-breaking linear stability analysis of fluid flow between two rotating cylinders has had an enormous impact on the field of fluid mechanics. The paper's influence has extended to general rotating flows, geophysical flows and astrophysical flows, not to mention its significance in firmly establishing several foundational concepts in fluid mechanics that are now broadly accepted. This two-part issue includes review articles and research articles spanning a broad range of contemporary research areas, all rooted in Taylor's landmark paper. This article is part of the theme issue 'Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical Transactions paper (part 1)'.

Integration of Demonstrative Teaching and Supporting Theories of Fluid Mechanics: A Literature Review

This review will give emphasis to the concept of demonstrative teaching to better improve the learning process of students in fluid mechanics. This paper is going to tackle the possible techniques students do to gain a better understanding of the concepts of fluid mechanics. With that, this review will also look at the impact of learning towards the students based on the number of demonstrations that they are making. This is where we will find out if there is a significant difference in the results with respect to the number of demonstrations performed. This paper will also discuss the most appropriate approach a beginner may take in handling a fluid mechanics class.

Sorting Out Where the Sand Flows During Fracturing

The message from a single chart’s data from the first full-scale hydraulic fracturing surface test is simple: Far less proppant flows out of the first clusters passed in a stage than the last ones. The likely explanation drawn from a surface test created by GEODynamics is that the momentum of those relatively large sand grains prevents them from making that turn early on, leaving a lot of sand for later stages where the slowing flow will make the turn easier. “The flow is going 45 miles an hour; sand particles have to turn in three-eighths of an inch,” said Jack Kolle, senior technical advisor at a sister company, Oil States Energy Services. He made the comment during a presentation about modeling fracturing test data to create an engineering model of proppant flows during at the recent SPE Hydraulic Fracturing Technology Conference and Exhibition (SPE 209178). When he first heard about the test results, Kolle thought he could create a model by using basic fluid mechanics concepts. After he started working on a model, though, he realized that proppant flow was more complex than expected. “It quickly became apparent we could not explain it without CFD modeling,” he said. He was referring to computational flow dynamics (CFD) which requires massive amounts of computing power to model complex flows such as the flow of air around an aircraft wing. In the past it has been used in studies that concluded that the fast-moving flow of water and sand during fracturing resulted in uneven distribution of water and sand. The model he created based on data from GEODynamic’s unique surface testing setup and subsurface fracturing analysis evolved into the company’s fracturing-flow advisor program, StageCoach. Based on a quick look at four charts in a paper about the testing, it appears that larger-grained proppant is far more likely to slip past early clusters than smaller grains, which tend to be distributed evenly among clusters. And fracturing designs that more evenly distribute the slurry among the clusters can further flatten the distribution (SPE 209141). The results favor some established trends. The industry has embraced 100 mesh proppant for fracturing and limited-entry designs which, to varying degrees, ensure more-even distribution. What constitutes limited entry has evolved. A 2019 paper on the first two rounds of testing preceded current stage designs using clusters with only one perforation per cluster, often at the top of the hole. The test work supported the rule of thumb that shooting perforations at the bottom of the casing is a bad idea. The thinking has been that a perf gun lying on the bottom of the casing and shooting at point-blank range will create a larger hole than shots made from a distance. When fracturing begins, bottom holes will take in far more of the fluid and proppant, causing rapid wear which is magnified by the force of gravity.

Elements of the anthropological theory of didactics in the selection of contents in a course of fluid mechanics in engineering, a case study in Spanish universities

The Anthropological Theory of Didactics has been applied to the field of didactics of mathematics with remarkable success. Fluid Mechanics is a discipline with a strong mathematical background, where mathematics is used for modeling the continuous nature. In addition, the Fluid Mechanics concepts are essential for the future engineer or scientist. For this reason, it is worth thinking whether the content that developed in engineering schools or science faculties are those demanded by the future professionals. The analysis has been done within the context of a case study framed in the Spanish noosphere, more particularly Universities and Companies. In this direction, the objective of this article is to know the institutional distance between the University and society as a demander of technologies based on Fluid Mechanics. To this end, the methodology based on the issuance of a questionnaire to experts focused on aspects such as present and emerging content associated with the Fluid Mechanics of an engineering degree is used. Note that the number of experts selected is reduced so as to consider the study as a sourcing for introducing expert thoughts on the fluid mechanics conception between university and companies. The results highlight the existence of an institutional distance between the University and the Enterprise (as a technology executor) in the conception of contents, thus establishing an area of potential improvement within the noosphere associated with fluid mechanics in Spain.HighlightsQuestionnaire to experts to understand the current institutional relations between University and Company in the Spanish system.Application of the Anthropological Theory of Didactics (ATD) techniques to Fluid Mechanics.Confirmation of an institutional distance between University and Companies in Fluid Mechanics conceptions.

The force generation mechanism of lifting surfaces with flow separation

Fins, wings, blades and sails can generate lift and drag in both attached and separated flow conditions. However, the common understanding of the lift generation mechanism holds only for attached flow conditions. In fact, when massive flow separation occurs, the underlying assumptions of thin airfoil theory and lifting line theory are violated and the concept of bound circulation cannot be applied. Therefore, there is a need to develop an intuitive understanding of the force generation mechanism that does not rely on these assumptions. This paper aims to address this issue by proposing a paradigm based on established concepts in theoretical fluid mechanics, and impulse theory in particular. The force generation can be intuitively associated with the vorticity field, which can be gathered with computational fluid dynamics or particle image velocimetry. This paradigm reconciles key known results about wing aerodynamics, and provides designers of lifting surfaces a measurable objective to optimise the shape in separated flow conditions. It will hopefully underpin both a deeper understanding of how lift and drag are generated, and the development of low order models in different fields of application.

Hybrid Computational Model to Assist in the Location of Victims Buried in the Tragedy of Brumadinho

This paper presents a hybrid computational model based on regression techniques, machine learning and physicomathematical algorithms developed for assistance in locating victims in the Brumadinho tragedy in 2019. The physicomathematical model, which provided results to help search teams, is based on integral and vector calculus, and fluid mechanics concepts. In addition, from data provided by the physicomathematical algorithm, two hybrid model were developed. One of them uses regression statistical and the other one uses support vector regression which is a type of machine learning. With good prospects of the advances in research, it is expected in future work, a more accurate model that can be used in other possible situations of dam-break. Moreover the model can be applied to situations involving computational fluid dynamics in general

How to Choose a Shunt for Patients with Normal Pressure Hydrocephalus: A Short Guide to Selecting the Best Shunt Assembly.

Most patients with hydrocephalus are still managed with the implantation of a cerebrospinal fluid (CSF) shunt in which the CSF flow is regulated by a differential-pressure valve (DPV). Our aim in this review is to discuss some basic concepts in fluid mechanics that are frequently ignored but that should be understood by neurosurgeons to enable them to choose the most adequate shunt for each patient. We will present data, some of which is not provided by manufacturers, which may help neurosurgeons in selecting the most appropriate shunt. To do so, we focused on the management of patients with idiopathic “normal-pressure hydrocephalus” (iNPH), as one of the most challenging scenarios, in which the combination of optimal technology, patient characteristics, and knowledge of fluid mechanics can significantly modify the surgical results. For a better understanding of the available hardware and its evolution over time, we will have a second look at the design of the first DPV and the reasons why additional devices were incorporated to control for shunt overdrainage and its related complications. We try to persuade the reader that a clear understanding of the physical concepts of the CSF and shunt dynamics is key to understand the pathophysiology of iNPH and to improve its treatment.

The Effectiveness of Web-Based Recitation Program on Improving Students’ Conceptual Understanding in Fluid Mechanics

A web-based recitation program has been developed to improve students’ conceptual understanding of some fundamental concepts of fluid mechanics. The program consists of multiple-choices conceptual questions followed by immediate feedback for each option. This study aimed to examine the effectiveness of the program and whether the program can be used by students without any assistance of instructor. If it is the case, the program could be used by instructor to serve recitation program outside the classroom. To address the objectives, this study employed a non-randomized control group pretest-posttest design involving three groups of students. The first group (E-1) used the program accompanied by teaching assistant, the second group (E-2) used the program by his/herself without assistance, and the third group (C) learned by his/herself without the program. The study involved 73 students enrolling the introductory physics course in physics education department, State University of Malang, as the subject. The effectiveness of the program was analyzed by comparing N-gain scores of the three groups and the responses of the E-1 and E-2 students to the program. Pretest was administered after the three groups of students have learned fluid mechanics through regular lecture sessions, and the posttest was administered after the E-1 and E-2 groups have finished learning with the help of the program. The results showed that the N-gain of group E-1, E-2, and C was 0.51 (upper medium), 0.58 (upper medium), and 0.12 (low), respectively. The ANOVA test showed that the three N-gain values were statistically different (p = 0,000). The LSD post hoc test showed that the N-gain of group C was significantly different from that of group E-1 and E-2 (p=0.000), whereas the N-gain between group E-1 and E-2 was not significantly different (p=0.244). It can be concluded that the web-based recitation program was effective to improve the students’ conceptual understanding of fluid mechanics and can be used equally well with or without direct assistance from instructor or teaching assistant. The students that used the program also gave quite positive responses to the program, that the program could help them to reflect on the appropriateness of their understanding, was easy to use, and had attractive features.

Modeling heat transfer in fluid flow near a decelerating rotating disk with variable fluid properties

Present work formulates the unsteadily revolving fluid flow caused by a rotating porous disk in a variable viscosity fluid. Following an existing paper, the disk angular velocity is assumed to exhibit an inversely linear time dependency. Moreover, temperature dependency in fluid viscosity is incorporated in the analysis. Two different numerical approaches namely, a modified finite difference scheme and the collocation method based MATLAB package bvp4c, are employed to find self-similar solutions. Subtle fluid mechanics concepts such as radial wall stress, torque required, volumetric flow rate and heat transfer rate are analyzed for full range of unsteadiness parameter S, measuring the decay rate of disk angular velocity. There exists a particular value of S designated as S∗ which corresponds to zero torque (G′(0) = 0) illustrating the situation of freely rotating disk. Beyond this value of S, that is S < S∗, G ′ (0) has a negative sign signaling that fluid's angular velocity becomes higher than that of the disk. Our emphasis is to seek how the said flow model is affected by variable fluid properties. It should be remarked here that variable viscosity/thermal conductivity considerably alters the overall drag coefficient as well as heat transfer rate.

Galilean-Invariant Expression for Bernoulli’s Equation

AbstractThe Bernoulli principle is one of the basic and most famous concepts in fluid mechanics, and the related equation is an extremely useful and effective tool in the solution of a wide range o...

Using Legitimation Code Theory to Conceptualize Learning Opportunities in Fluid Mechanics

With widespread industry feedback on engineering graduates’ lack of technical skills and research demonstrating that higher education does not effectively facilitate the development of open-ended problem-solving competencies, many educators are attempting to implement measures that address these concerns. In order to properly formulate sensible interventions that result in meaningful improvements in student outcomes, useful educational measurement and analysis approaches are needed. Legitimation Code Theory (LCT) has rapidly emerged as an effective, theoretically informed ‘toolkit’ offering a suite of dimensions through which to observe, analyze, interpret, and design teaching and learning practices. LCT Semantics has been used to help engineering educators unpack both levels of engineering knowledge abstraction and the complexity of engineering terms, while LCT Specialization focuses on knowledge practices (using the epistemic plane) and enables a visualization and differentiation between kinds of phenomena and the fixed versus open-ended methods with which to approach a particular phenomenon. Drawing on a range of initiatives to enable an improved practical grasp of fluid mechanics concepts, this paper presents a description and graphic LCT analysis of student learning that has been designed to anchor the ‘purist’ principles underpinning applied fluid mechanics concepts (such as in piping and pump network design) by way of concerted ‘doctrinal’ practices, and the exposure to more open-ended practical situations involving peer learning/group work, allowing educators to visualize the code clash between the curriculum and the world of work.

Alat Peraga Sebagai Upaya Peningkatan Pemahaman Konsep Peserta didik Pada Materi Mekanika Fluida

This research is aimed to increase students' understanding of the concepts of fluid mechanics by applying teaching aids. The research method uses pre-experiment. The research design uses the One Group Pretest-Posttest Design. Data collection techniques using the test of understanding the concept of fluid mechanics as many as 10 essay questions. N-gain test is used to determine the increase in understanding of the concepts of learning outcomes before and after being taught using teaching aids. The results showed that learning by using instructional media in the form of fluid mechanics teaching aids influences students' understanding of concepts by 0.71 with high criteria. This proves that there is an increase in students' understanding of the concepts of fluid mechanics.

Forty Years’ Experience in Teaching Fluid Mechanics at Strasbourg University

A summary of the personal investment in teaching fluid mechanics over 40 years in a French university is presented. Learning and Teaching Science and Engineering has never been easy, and in recent years it has become a crucial challenge for curriculum developers and teaching staff to offer attractive courses and optimized assessments. One objective is to ensure that students acquire competitive skills in higher science education that enable them to compete in the employment market, as the mechanical field is a privileged sector in industry. During the last decade, classical learning and teaching methods have been coupled with hands-on practice for future schoolteachers in a specific course on subjects including fluid mechanics. The hands-on/minds-on/hearts-on approach has demonstrated its effectiveness in training primary school teachers, and fluids are certainly a nice source of motivation for pupils in science learning. In mechanical engineering, for undergraduate and graduate students, the development of teaching material and the learning and teaching experience covers up to 40 years, mostly on fluid dynamics and related topics. Two periods are identified, those prior to and after the Bologna Process. Most recently, teaching instruction has focused on the Fluid Mechanics Concept Inventory (FMCI). This inventory has been recently introduced in France, with some modifications, and remedial tools have been developed and are proposed to students to remove misconceptions and misunderstandings of key concepts in fluid mechanics. The FMCI has yet to be tested in French higher education institutions, as are the innovative teaching methods that are emerging in fluid mechanics.

Fun with fluid: An innovative assignment in fluid mechanics

Fluid mechanics (FM) is a core course of the Chemical (ChE), Mechanical, Civil, and Aerospace Engineering programs. The general expectation is that students should be able to demonstrate the fundamentals learnt in theory and get hands-on experience during the lab course. In this regard, the author of this paper organized an assignment plus competition entitled “Fun with Fluid” (FwF). The event had the following four segments: (1) fun with fluid, (2) frugal lab, (3) design of a thought problem, and (4) a PowerPoint presentation of the FM concepts. The author of this paper had two cabin meetings with each group (registration/guidance in selecting topic and presentation rehearsal). Through this assignment, students were able to design and conduct experiments. Additionally, it gave them a chance to assess their communication ability, work with multidisciplinary teams, and understand contemporary issues. Each exhibit was evaluated in three stages. Before the event, instructor and teaching assistants assessed projects while for evaluation during the event three experts from outside the institute were invited. Evaluation was based on scientific content, novelty, presentation and questions-answer session. Since 2015 FwF is an annual activity. Videos of exhibits are available on YouTube.