Mechanics of a plant in fluid flow

AbstractPlants live in constantly moving fluid, whether air or water. In response to the loads associated with fluid motion, plants bend and twist, often with great amplitude. These large deformations are not found in traditional engineering application and thus necessitate new specialized scientific developments. Studying fluid–structure interaction (FSI) in botany, forestry, and agricultural science is crucial to the optimization of biomass production for food, energy, and construction materials. FSIs are also central in the study of the ecological adaptation of plants to their environment. This review paper surveys the mechanics of FSI on individual plants. I present a short refresher on fluid mechanics then dive into the statics and dynamics of plant–fluid interactions. For every phenomenon considered, I examine the appropriate dimensionless numbers to characterize the problem, discuss the implications of these phenomena on biological processes, and propose future research avenues. I cover the concept of reconfiguration while considering poroelasticity, torsion, chirality, buoyancy, and skin friction. I also assess the dynamical phenomena of wave action, flutter, and vortex-induced vibrations.

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Review on the Use of Artificial Intelligence to Predict Fire Performance of Construction Materials and Their Flame Retardancy

Molecules ◽

10.3390/molecules26041022 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1022

Author(s):

Hoang T. Nguyen ◽

Kate T. Q. Nguyen ◽

Tu C. Le ◽

Guomin Zhang

Keyword(s):

Artificial Intelligence ◽

Flame Retardancy ◽

Material Science ◽

Construction Materials ◽

Engineering Problem ◽

Future Research ◽

Fire Performance ◽

Structural Components ◽

Comprehensive Overview ◽

Fire Engineering

The evaluation and interpretation of the behavior of construction materials under fire conditions have been complicated. Over the last few years, artificial intelligence (AI) has emerged as a reliable method to tackle this engineering problem. This review summarizes existing studies that applied AI to predict the fire performance of different construction materials (e.g., concrete, steel, timber, and composites). The prediction of the flame retardancy of some structural components such as beams, columns, slabs, and connections by utilizing AI-based models is also discussed. The end of this review offers insights on the advantages, existing challenges, and recommendations for the development of AI techniques used to evaluate the fire performance of construction materials and their flame retardancy. This review offers a comprehensive overview to researchers in the fields of fire engineering and material science, and it encourages them to explore and consider the use of AI in future research projects.

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Bringing optical metrology to testing and inspection activities in civil engineering

ACTA IMEKO ◽

10.21014/acta_imeko.v10i3.1059 ◽

2021 ◽

Vol 10 (3) ◽

pp. 108

Author(s):

Luis Martins ◽

Álvaro Ribeiro ◽

Maria Do Céu Almeida ◽

João Alves e Sousa

Keyword(s):

Large Scale ◽

Civil Engineering ◽

National Laboratory ◽

Research Work ◽

Construction Materials ◽

Laser Interferometry ◽

Suspension Bridge ◽

Shaking Table ◽

Optical Metrology ◽

Future Research

Optical metrology has an increasing impact on observation and experimental activities in Civil Engineering, contributing to the Research and development of innovative, non-invasive techniques applied in testing and inspection of infrastructures and construction materials to ensure safety and quality of life. Advances in specific applications are presented in the paper, highlighting the application cases carried out by LNEC (the Portuguese National Laboratory for Civil Engineering). The examples include: (i) structural monitoring of a long-span suspension bridge; (ii) use of close circuit television (CCTV) cameras in drain and sewer inspection; (iii) calibration of a large-scale seismic shaking table with laser interferometry; (iv) destructive mechanical testing of masonry specimens.Current and future research work in this field is emphasized in the final section. Examples given are related to the use of Moiré techniques for digital modelling of reduced-scale hydraulic surfaces and to the use of laser interferometry for calibration of strain measurement standard for the geometrical evaluation of concrete testing machines.

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Materiality assessment: the case of Latin American listed companies

Sustainability Accounting Management and Policy Journal ◽

10.1108/sampj-10-2020-0358 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Yully Marcela Sepúlveda-Alzate ◽

María Antonia García-Benau ◽

Mauricio Gómez-Villegas

Keyword(s):

Latin American ◽

Social Issues ◽

Construction Materials ◽

Field Research ◽

Principal Component ◽

Sustainability Reporting ◽

Listed Companies ◽

Future Research ◽

Content Type ◽

Sustainability Reports

Purpose This paper aims to propose a measurement of the materiality of environmental, social and governance information (ESG) reported by listed companies belonging to sensitive industries in Colombia, Mexico, Brazil, Chile and Argentina. This analysis is carried out from the insights of stakeholder theory, legitimacy theory and institutional theory. The research questions addressed are: What type of information is considered as material by Latin American companies? Does this information respond to the environmental and social issues within the context of Latin American companies and the needs of their stakeholders? Design/methodology/approach A materiality index is developed from principal component analysis and factor analysis, which are multivariate analysis statistical techniques used in various fields to develop indices. The designed index examines materiality in the sustainability reports of 65 companies for 2017 and 67 companies for 2018. These firms belong to the energy, mining, chemical, construction, construction materials and public services industries in Colombia, Mexico, Chile, Argentina and Brazil. Findings The results show medium-high materiality indices, mostly in Chilean, Mexican and Colombian companies. In addition, issues such as water management, climate change and occupational health and safety are particularly interesting for companies. For the two years studied and from the perspective of material aspects for the company and its stakeholders, energy, mining and utilities (drinking water and sewage) sectors obtained the highest scores. This shows that the disclosure of ESG information is higher in industries related to the exploitation of natural resources that cause adverse effects on the environment such as extractive industries. Both the analysis presented in this paper and the materiality measurement developed, allow social responsibility managers to have a standard on the level of importance allotted to the different topics disclosed in sustainability reports. Additionally, this study provides a perspective of the material issues recognized by sensitive industries with great environmental impact. Similarly, an analysis of the issues considered material by stakeholders is provided. This allows such issues to be compared, identifying similarities and differences among the issues regarded as material by a company and its stakeholders. Practical implications The paper opens the debate is open as to whether the information disclosed response to the needs of stakeholders or whether, on the contrary, the materiality analysis is a process that emerges simply from the interests of the company. These demands for qualitative and field research to complement quantitative studies such as this one to research the stakeholders’ engagement processes in context. Social implications The paper’s purpose a challenge for future research is to strengthen the use of various methodologies that allow knowing the participation processes in the definition of materiality in the ESG information and the companies’ engagement with stakeholders. This stimulates research in the region, which is still in its infancy. Originality/value The international literature contains few studies related to the assessment of materiality for sustainability reporting. So this paper contributes proposes measurement of materiality for ESG information.

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Effect of Soil Organic Matters in Dredged Soils to Utilization of their Mixtures Made with a Steel Slag

Materials ◽

10.3390/ma13235450 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5450

Author(s):

Kanako Toda ◽

Ryosuke Kikuchi ◽

Tsubasa Otake ◽

Satoshi Nishimura ◽

Yuzoh Akashi ◽

...

Keyword(s):

Humic Acid ◽

Steel Slag ◽

Construction Materials ◽

Engineering Application ◽

Pozzolanic Reaction ◽

Strength Development ◽

Organic Matters ◽

Development Indicators ◽

Dredged Soil ◽

Accelerate Evaluation

Dredged soils have been used as construction materials by alkaline activation with steel slag (steel slag-dredged soil mixtures) at harbors. Such mixtures develop strength chiefly by calcium silicate hydrate (C-S-H) formation by the pozzolanic reaction. However, the strength of such mixtures is unpredictable, and in some cases, mixtures have been too soft for the intended engineering application. An identification of strength development indicators would accelerate evaluation processes for strength development to facilitate and promote the utilization of such materials. This paper focuses on the relationship between the characteristics of soil organic matters in dredged soils and the strength development of the mixtures by a comparison of eight dredged soils collected from eight different Japanese harbors. The characteristics of the soil organic matters were identified to determine as indicators of mixtures with weak strength development, i.e., enriched sulfur content in extracted soil organic matter (humic acid) fraction, and the N/C ratio of humic acid similar to land humic acid standards. Increases in the validated fraction of dredged soils and steel slag by replacing fractions disadvantageous to construction resources would contribute to reduce waste production, which would lower the environmental impact of the use, aiming to achieve sustainable utilization of such materials.

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How Reliable is the Cuprates System to Recent Technology?

International Journal of Electrical and Computer Engineering (IJECE) ◽

10.11591/ijece.v6i4.10082 ◽

2016 ◽

Vol 6 (4) ◽

pp. 1534

Author(s):

Emetere M.E. ◽

Awojoyogbe O.B. ◽

Uno U.E. ◽

Isah K.U. ◽

Sanni E.S. ◽

...

Keyword(s):

Critical Temperature ◽

Room Temperature ◽

Engineering Application ◽

Experimental Results ◽

Future Research ◽

Mathematical Approach ◽

Experimental Room ◽

High Tc ◽

High Tc Superconductor

The emergence of cuprates as a high Tc superconductor gave high hopes in the discovery of a room temperature superconductor. It is almost three decades and the highest critical temperature attained on the cuprates is about 135K. A brief overview was conducted on the progress made so far on the cuprates. A mathematical approach was used to design a formula which could determine the experimental results of critical temperature of versed cuprates superconductors. The result of our findings shows that the possibility of attaining the experimental room temperature cuprates superconductor seems very narrow. The study recommended an elaborate approach on the hybridization of cuprates for future research. Hence, there is possibility of having cuprates with wide engineering application.

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The Role of Coulombic Forces in Quasi-Two Dimensional Electrochemical Deposition

MRS Proceedings ◽

10.1557/proc-451-147 ◽

1996 ◽

Vol 451 ◽

Cited By ~ 3

Author(s):

G. Marshall ◽

P. Mocskos ◽

F. Molina ◽

S. Dengra

Keyword(s):

Numerical Modeling ◽

Pattern Formation ◽

Electrochemical Deposition ◽

Growth Pattern ◽

Stokes Equations ◽

Fluid Motion ◽

Navier Stokes ◽

Experimental Measurements ◽

Dimensionless Numbers ◽

Navier Stokes Equations

ABSTRACTRecent work demonstrates the relevant influence of convection during growth pattern formation in thin-layer electrochemical deposition. Convection is driven mainly by coulombic forces due to local charges at the tip of the aggregation and by buoyancy forces due to concentration gradients. Here we study through physical experiments and numerical modeling the regime under which coulombic forces are important. In the experimental measurements fluid motion near the growing tips of the deposit is visualized with neutrally buoyant latex spheres and its speed measured with videomicroscope tracking techniques and image processing software. The numerical modeling consists in the solution of the 2D dimensionless Nernst-Planck equations for ion concentrations, the Poisson equation for the electric field and the Navier-Stokes equations for the fluid flow, and a stochastic growth rule for ion deposition. A new set of dimensionless numbers governing electroconvection dominated flows is introduced. Preliminary experimental measurements and numerical results indicate that in the electroconvection dominated regime coulombic forces increase with the applied voltage, and their influence over growth pattern formation can be assessed with the magnitude of the dimensionless electric Froude number. It is suggested that when this number decreases the deposit morphology changes from fractal to dense branching.

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Indoor Nanoparticle Characterization in Construction Waste Recycling Companies over Time

Sustainability ◽

10.3390/su132414071 ◽

2021 ◽

Vol 13 (24) ◽

pp. 14071

Author(s):

Diana Pinto ◽

Alcindo Neckel ◽

Guilherme L. Dotto ◽

Bashir Adelodun

Keyword(s):

Fine Particles ◽

Morphological Changes ◽

Construction Materials ◽

Waste Recycling ◽

Particulate Material ◽

Future Research ◽

Material Recycling ◽

Four Seasons ◽

Electron Microscopes ◽

Ultra Fine Particles

Building activity is a significant source of atmospheric contamination by ultrafine dust. Cognizant of this fact, those active in the use and recycling of construction materials must be aware of the risks associated with exposure to nanoparticles (NPs) and ultra-fine particles (UFPs), as well as the associated health impacts. This work analyzed NPs and UFPs generated in a small building-material recycling company using high-resolution electron microscopes and X-ray Diffraction. A self-made passive sampler (LSPS) that can obtain particulate samples without physical and morphological changes, especially where there is a suspension of particulate material, was used in this study. A total of 96 particulate samples, using the LSPS for three months in four seasons, were collected during the study. Thus, the dry deposition of the particles, which are considered highly harmful to human health, was found in each of the four seasons of the year. It is suggested that for future research, the toxicological evaluations of the particulates in the construction industry should be investigated through the consideration of measures to control and mitigate the health risks of workers regarding exposure to NPs and UFPs.

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Investigating the Relationship between Construction Supply Chain Integration and Sustainable Use of Material: Evidence from China

Sustainability ◽

10.3390/su10103581 ◽

2018 ◽

Vol 10 (10) ◽

pp. 3581 ◽

Cited By ~ 7

Author(s):

Ningshuang Zeng ◽

Yan Liu ◽

Chao Mao ◽

Markus König

Keyword(s):

Supply Chain ◽

Structural Equation ◽

Sustainable Use ◽

Construction Materials ◽

Supply Chain Integration ◽

Equation Modeling ◽

Future Research ◽

Management Perspective ◽

Whole Life Cycle ◽

Material Evidence

Environmental burdens arise in the whole life cycle of construction. Waste and pollution are produced in the upstream and downstream of a construction project along the supply chains. The interdependency between on-site construction and off-site logistics also leads to an expansion effect of waste when a disturbance occurs. A related supply chain activated by construction activities should be taken into account to improve the sustainability in construction from a material and waste management perspective. However, it is unknown how the supply chain integration could contribute to the sustainable use of materials in construction. Therefore, an empirical investigation is conducted. A research model with eight latent-constructs is designed through a comprehensive literature review, and 70 completed survey questionnaires are received. Using PLS-SEM (partial least squares-structural equation modeling), sample data is analyzed and seven research hypotheses are examined. Results support the assumption that the construction supply chain integration had a positive correlation with the sustainable use of construction materials. Discussion and relevant suggestions are given for the future research.

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Extension of the Wall-Driven Enclosure Flow Problem to Toroidally Shaped Geometries of Square Cross-Section

Journal of Fluids Engineering ◽

10.1115/1.2835509 ◽

1996 ◽

Vol 118 (4) ◽

pp. 779-786 ◽

Cited By ~ 5

Author(s):

L. M. Phinney ◽

J. A. C. Humphrey

Keyword(s):

Cross Section ◽

Fluid Motion ◽

Radius Of Curvature ◽

Two Dimensional ◽

Coordinate Direction ◽

Concave Wall ◽

Center Vortex ◽

Convex Wall ◽

Two Dimensional Flow ◽

Moving Fluid

The two-dimensional wall-driven flow in an enclosure has been a numerical paradigm of long-standing interest and value to the fluid mechanics community. In this paradigm the enclosure is infinitely long in the x-coordinate direction and of square cross-section (d × d) in the y-z plane. Fluid motion is induced in all y-z planes by a wall (here the top wall) sliding normal to the x-coordinate direction. This classical numerical paradigm can be extended by taking a length L of the geometry in the x-coordinate direction and joining the resulting end faces at x = 0 and x = L to form a toroid of square cross-section (d × d) and radius of curvature Rc. In the curved geometry, axisymmetric fluid motion (now in the r-z planes) is induced by sliding the top flat wall of the toroid with an imposed radial velocity, ulid, generally directed from the convex wall towards the concave wall of the toroid. Numerical calculations of this flow configuration are performed for values of the Reynolds number (Re = ulidd/ν) equal to 2400, 3200, and 4000 and for values of the curvature ratio (δ = d/Rc) ranging from 5.0 · 10−6 to 1.0. For δ ≤ 0.05 the steady two-dimensional flow pattern typical of the classical (straight) enclosure is faithfully reproduced. This consists of a large primary vortex occupying most of the enclosure and three much smaller secondary eddies located in the two lower corners and the upper upstream (convex wall) corner of the enclosure. As δ increases for a fixed value of Re, a critical value, δcr, is found above which the primary center vortex spontaneously migrates to and concentrates in the upper downstream (concave wall) corner. While the sense of rotation originally present in this vortex is preserved, that of the slower moving fluid below it and now occupying the bulk of the enclosure cross-section is reversed. The relation marking the transition between these two stable steady flow patterns is predicted to be δcr1/4 = 3.58 Re-1/5 (δ ± 0.005).

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Solidification of Pure Liquids and Liquid Mixtures Inside Ducts and Over External Bodies

Applied Mechanics Reviews ◽

10.1115/1.3111067 ◽

1994 ◽

Vol 47 (12) ◽

pp. 589-621 ◽

Cited By ~ 4

Author(s):

Shoichiro Fukusako ◽

Masahiko Yamada

Keyword(s):

Binary Systems ◽

Transport Phenomena ◽

Fluid Motion ◽

Liquid Mixtures ◽

Transport Processes ◽

Future Research ◽

Density Gradients ◽

Research Needs ◽

Recent Advances ◽

Pure Substances

Recent advances in the understanding of transport phenomena during solidification inside ducts and over external bodies are discussed. The emphasis is on fundamental aspects of the phenomena observed in transport processes during solidification. After a discussion of the solidification of pure substances, transport processes during solidification of binary systems are reviewed. The important role played by fluid motion owing to density gradients is also discussed and future research needs are assessed.

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