Sensitivity analysis of nanofluid flow over different flat tubes confined between two parallel plates using Taguchi method and statistical analysis of variance

AbstractPurpose. The aim of the study was to determine differences in anteroposterior spine curvatures between futsal players, soccer players, and non-training students. The results may contribute to the development of present-day knowledge of posturometry, and its implementation in training can help reduce the risk of body posture disorders in athletes. Methods. The examined group consisted of 48 athletes and 38 non-training college students. Body posture parameters were measured with the use of Posturometr-S. The normality of distribution was checked with the Shapiro-Wilk test, and the differences between the groups were measured with ANOVA and the Bonferroni post-hoc test. The level of statistical significance was set at p < 0.05. Results. The analysis of angle values revealed the widest and most similar measurements in the group of futsal players and soccer players. The analysis of variance proved statistically significant differences between the soccer players and futsal players (p = 0.003). The difference between the soccer players and non-training students was statistically significant. The highest γ angular value was measured in non-training students, followed by futsal players and soccer players. The statistical analysis revealed significant differences between the non-training students and futsal players, as well as non-training students and soccer players (p < 0.001). Conclusions. A complex assessment of athletes’ body posture is crucial in injury prevention. Training overloads may often lead to disorders of the organ of locomotion and affect the correct body posture in athletes. This, in turn, may result in pains and injuries.

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A generalized perspective of Fourier and Fick’s laws: Magnetized effects of Cattaneo-Christov models on transient nanofluid flow between two parallel plates with Brownian motion and thermophoresis

Nonlinear Engineering ◽

10.1515/nleng-2020-0009 ◽

2020 ◽

Vol 9 (1) ◽

pp. 201-222 ◽

Cited By ~ 1

Author(s):

Usha Shankar ◽

Neminath B. Naduvinamani ◽

Hussain Basha

Keyword(s):

Brownian Motion ◽

Joule Heating ◽

Concentration Field ◽

Double Diffusion ◽

Diffusion Models ◽

Time Dependent ◽

Parallel Plates ◽

Nanofluid Flow ◽

Casson Nanofluid ◽

Highly Nonlinear

AbstractPresent research article reports the magnetized impacts of Cattaneo-Christov double diffusion models on heat and mass transfer behaviour of viscous incompressible, time-dependent, two-dimensional Casson nanofluid flow through the channel with Joule heating and viscous dissipation effects numerically. The classical transport models such as Fourier and Fick’s laws of heat and mass diffusions are generalized in terms of Cattaneo-Christov double diffusion models by accounting the thermal and concentration relaxation times. The present physical problem is examined in the presence of Lorentz forces to investigate the effects of magnetic field on double diffusion process along with Joule heating. The non-Newtonian Casson nanofluid flow between two parallel plates gives the system of time-dependent, highly nonlinear, coupled partial differential equations and is solved by utilizing RK-SM and bvp4c schemes. Present results show that, the temperature and concentration distributions are fewer in case of Cattaneo-Christov heat and mass flux models when compared to the Fourier’s and Fick’s laws of heat and mass diffusions. The concentration field is a diminishing function of thermophoresis parameter and it is an increasing function of Brownian motion parameter. Finally, an excellent comparison between the present solutions and previously published results show the accuracy of the results and methods used to achieve the objective of the present work.

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Fuel and lubricant consumption in felling the young oak-hornbeam stands

Glasnik Sumarskog fakulteta ◽

10.2298/gsf0286059b ◽

2002 ◽

pp. 59-66

Author(s):

Vojislav Bajic ◽

Milorad Danilovic

Keyword(s):

Statistical Analysis ◽

Analysis Of Variance ◽

Unit Area ◽

Function Form ◽

Tree Diameter ◽

Significant Difference ◽

The Difference ◽

Level Of Significance ◽

Average Consumption

Based on the elements of statistical analysis on the dependence of fuel and lubricant consumption on tree diameter, it was assessed that with the increase of tree diameter, the fuel and lubricant consumption in the young oak and hornbeam stands decreases significantly, both in clear felling and in thinning and that the function form Y=exp(a+b x X?1) is the best description of the correlation The consumption of fuel compared to lubricant consumption is almost double, which agrees with the results of the previous studies. Average consumption of fuel and lubricant is 17.43 mL x tree?1, on the plots 20.27 mL x tree?1, average consumption of lubricant per tree on skid roads is 9.4 mL x tree?1, on the plots 11 mL x tree?1. The higher consumption of fuel and lubricant on the plots with selective thinning is the consequence of the longer time needed for the conversion per tree, compared to that in clear felling The consumption of fuel per unit area on the skid roads (clear felling) is 22.9 L x ha?1, on the plots (selective thinning) 7.6 L x ha?1. The consumption of lubricant on the skid roads is 13.3 L x ha?1, on the plots 4.29 L x ha?1. The higher consumption of fuel and lubricant per unit area on the skid roads is due to the difference in the number of trees per unit area Based on the results of the analysis of variance, it was found out that between fuel and lubricant consumption in selective thinning and in felling the trees along tractor skid roads there is no statistically significant difference at the level of significance of 95%. So, for practical purposes, the unique norms of consumption can be established for the stands similar to those in which the study was performed.

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Flank Wear Modelling in High Speed Hard Milling of AISI D2 Steel

International Journal of Engineering Materials and Manufacture ◽

10.26776/ijemm.05.02.2020.03 ◽

2020 ◽

Vol 5 (2) ◽

pp. 50-54

Author(s):

Muataz Al Hazza ◽

Khadijah Muhammad

Keyword(s):

Statistical Analysis ◽

Wear Rate ◽

Taguchi Method ◽

Feed Rate ◽

High Speed ◽

Flank Wear ◽

Cutting Speed ◽

Depth Of Cut ◽

High Speed Machining ◽

Aisi D2

High speed machining has many advantages in reducing time to the market by increasing the material removal rate. However, final surface quality is one of the main challenges for manufacturers in high speed machining due to the increasing of flank wear rate. In high speed machining, the cutting zone is under high pressure associated with high temperature that lead to increasing of the flank wear rate in which affect the final quality of the machined surface. Therefore, one of the main concerns to the manufacturer is to predict the flank wear to estimate and predict the surface roughness as one of the main outputs of the machining processes. The aim of this study is to determine experimentally the optimum cutting parameters: depth of cut, cutting speed (Vc) and feed rate (f) that maintaining low flank wear (Vb). Taguchi method has been applied in this experiment. The Taguchi method has been universally used in engineering analysis. JMP statistical analysis software is used to analyse statically the development of flank wear rate during high speed milling of hardened steel AISI D2 to 60 HRD. The experiment was conducted in the following boundaries: cutting speed 200-400 m/min, feed rate of 0.01-0.05 mm/tooth and depth of cut of 0.1-0.2 mm. Analysis of variance ANOVA was conducted as one of important tool for statistical analysis. The result showed that cutting speed is the most influential input factors with 70.04% contribution on flank wear.

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Corrigendum by Simeon Oka, Editor-in-Chief of the Journal Thermal Science requested to replace .pdf file of the paper The effect of variable magnetic field on heat transfer and flow analysis of unsteady squeezing nanofluid flow between parallel plates using Galerkin method by Mohammad Rahimi-Gorji Oveis Pourmehran, Mofid Gorji-Bandpy and Davood Domiri Ganji, Published in the Journal Thermal Science, year 2017, vol. 21, no. 5, pp. 2057-2067; https://doi.org/10.2298/TSCI160524180R

Thermal Science ◽

10.2298/tsci171204246e ◽

2017 ◽

Vol 21 (6 Part B) ◽

pp. 3062-3062

Author(s):

E Editorial

Keyword(s):

Magnetic Field ◽

Heat Transfer ◽

Review Process ◽

Peer Review Process ◽

Flow Analysis ◽

Editorial Staff ◽

Variable Magnetic Field ◽

Parallel Plates ◽

Nanofluid Flow ◽

Font Color

Due to error of the Editorial staff, unrevised manuscript has been published instead of the REVISED MANUSCRIPT sent by authors after peer review process. The corrected version of this article is printed in this issue on pages pp. 3063-3073 Link to the corrected article <a href="http://dx.doi.org/10.2298/TSCI160524180R">10.2298/TSCI160524180R</a>

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EMERGÊNCIA E SOBREVIVÊNCIA DE PLANTAS DE SOJA A CAMPO EM RELAÇÃO ÀS PROFUNDIDADES E ÉPOCAS DE SEMEADURA

ENERGIA NA AGRICULTURA ◽

10.17224/energagric.2020v35n2p150-157 ◽

2020 ◽

Vol 35 (2) ◽

pp. 150-157

Author(s):

Patrícia Pereira Dias ◽

Saulo Fernando Gomes de Sousa ◽

Paulo Roberto Arbex Silva ◽

Tiago Pereira da Silva Correia ◽

Anderson Ravanny de Andrade Gomes

Keyword(s):

Glycine Max ◽

Statistical Analysis ◽

Field Experiment ◽

Analysis Of Variance ◽

Early Stage ◽

Soybean Seed ◽

Sowing Depth ◽

Tukey Test ◽

Glycine Max L ◽

Soil Deposition

A PROFUNDIDADE DE SEMEADURA DA SOJA NA PLANTABILIDADE PATRÍCIA PEREIRA DIAS1*, SAULO FERNANDO GOMES DE SOUSA2, PAULO ROBERTO ARBEX SILVA3, TIAGO PEREIRA DA SILVA CORREIA4 e ANDERSON RAVANNY DE ANDRADE GOMES5 * Parte do texto foi extraído da tese da autora 1 Departamento de Produção Vegetal, Universidade Estadual Paulista ‘Júlio de Mesquita Filho’ - Av. Universitária, 3780 - Altos do Paraíso, 18610-034, Botucatu - SP, Brasil. [email protected] 2 Agroefetiva, Rua Lourival Ferreira, 11 - Distrito Industrial III, 18608-853, Botucatu - SP, Brasil. [email protected] 3 Departamento de Engenharia Rural e Socioeconomia, Universidade Estadual Paulista ‘Júlio de Mesquita Filho’ - Av. Universitária, 3780 - Altos do Paraíso, 18610-034, Botucatu - SP, Brasil. [email protected] 4 Faculdade de Agronomia e Medicina Veterinária, Universidade de Brasília, Caixa - Campos Universitário Darci Ribeiro ICC – Asa Norte, 04508, Brasília - DF, Brasil. [email protected] 5 Faculdade Regional da Bahia, Rodovia AL 220, 3630 - Senador Arnon De Melo - Planalto, Arapiraca – AL, Brasil. [email protected] RESUMO: O objetivo deste trabalho foi avaliar a cultura da soja semeada a campo em diferentes profundidades das sementes e épocas de semeadura e, dessa maneira, saber o quanto esses fatores influenciam a emergência e sobrevivência das plantas. O experimento foi conduzido em dois anos agrícolas, 2015/16 e 2016/17, com sementes de soja cultivar 5D634, na Fazenda Lageado, da Faculdade de Ciências Agronômicas – UNESP, Botucatu (SP), Brasil. O delineamento foi de blocos ao acaso em esquema fatorial 6 × 2, com seis tratamentos referentes às profundidades das sementes na mesma linha de semeadura: 0,02, 0,05 e 0,08 m do nível do solo, e combinação e alternância entre eles: 0,02 e 0,05, 0,02 e 0,08, 0,05 e 0,08 m e duas épocas de semeadura: outubro e novembro, com quatro repetições, totalizando 48 parcelas. Para a análise estatística, os dados foram submetidos à análise de variância (ANOVA), utilizando o teste de Tukey a 5% de probabilidade. A perda foi acima de 10% no estande de plantas na semeadura mais profunda (0,08 m), aliada à menor precipitação (outubro/2016), que contribuiu significativamente para esse resultado. Desta forma, a plantabilidade é prejudicada com o erro da profundidade de semeadura, aqui representada pela emergência e sobrevivência de plantas. Palavras-chave: Glycine max L., Plantabilidade, Estande de plantas. THE SOYBEAN SOWING DEPTH IN PLANTABILITY ABSTRACT: The aim of this work was evaluate the sowing of soybean seed with error in soil deposition and different month of sowing. The field experiment was carried out during two years (2015 and 2016) at Fazenda Lageado, Faculty of Agronomic Sciences - UNESP / Botucatu - SP, Brazil. The plots were randomized blocks in 6 × 2 factorial, six treatments referring to the depth of the seeds in soil: 0.02 (T1); 0.05 (T2 - control) and 0.08 (T3); 0.02 and 0.05 (T4); 0.02 and 0.08 (T5); 0.05 and 0.08 m (T6) and two sowing times: October and November. For statistical analysis the data were submitted to analysis of variance (ANOVA) using Tukey test at 5% probability. The number of plants in early stage decreased by over 10% in the deep seeding (0.08 m), added to the less rainfall (October / 2016) which contributed significantly to this result. Therefore, plantability is damaged by the error of sowing depth, represented here by the emergence and survival of plants. Keywords: Glycine max L., Plantability, Early stage.

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Analytical Study of Heat Transfer of a Unsteady Newtonian Nanofluid Flow Problem

WSEAS TRANSACTIONS ON HEAT AND MASS TRANSFER ◽

10.37394/232012.2020.15.22 ◽

2020 ◽

Vol 15 ◽

Keyword(s):

Heat Transfer ◽

Volume Fraction ◽

Skin Friction Coefficient ◽

Parallel Plates ◽

Nanofluid Flow ◽

Shooting Technique ◽

Flow And Heat Transfer ◽

Transfer Behavior ◽

Basic Equations ◽

Squeeze Number

Heat transfer behavior of unsteady flow of squeezing nanofluid (Copper+water) between two parallel plates is investigated. By using the appropriate transformation for the velocity and temperature, the basic equations governing the flow and heat transfer were reduced to a set of ordinary differential equations. These equations subjected to the associated boundary conditions were solved analytically using Homotopy Perturbation Method and numerically using Runge-Kutta-Fehlberg method with shooting technique. Effects on the behavior of velocity and temperature for various values of relevant parameters are illustrated graphically. The skin-friction coefficient, heat transfer and Nusselt number rate are also tabulated for various governing parameters. The results indicate that, for nanofluid flow, the rates of heat transfer and velocity had direct relationship with squeeze number and nanoparticle volume fraction they are also a decreasing function of those parameters

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