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A. O. Nieckele et al.: Turbulent Heat Transfer and Pressure Drop in Pinned Annular Regions
Marcelo Becker
Name of institution and address for correspondence
e-mail, if any
Marcelo Becker
Name of institution and address for correspondence
e-mail, if any
Marcelo Becker
Name of institution and address for correspondence
e-mail, if any
Marcelo Becker
Name of institution and address for correspondence
e-mail, if any
Sascha Kolski
Name of institution and address for correspondence
e-mail, if any
2D Laser-based Motion Tracking in Urban-like Environments
Obstacle motion tracking is an essential ability for mobile robot. However, this task is not trivial in outdoor environments where a great quantity and variety of obstacles may induce the robot to take erroneous decisions. Unfortunately, obstacles close to his sensors frequently cause blind zones behind them where other obstacles could be hidden. In this situation, the robot may lose vital information about these obstructed obstacles that can provoke collisions. In order to overcome this problem an obstacle motion tracking module based only on 2D laser scan data was developed. Its main parts consist of obstacle detection, obstacle classification, and obstacle tracking algorithms. Different methods were evaluated for extracting data from the laser data. Geometrical feature extraction itself, i.e. lines and corners, was not found sufficient. Therefore, a motion detection module using scan matching was developed. Aiming to improve the data quality for navigation purposes, a probabilistic grid representation of the environment was also implemented. The research was initially conducted using a MatLab simulator that reproduces a simple 2D urban-like environment. Then the algorithms were validated using data samplings in real urban-like environments. On average the results proved the usefulness of considering obstacle paths and velocities while navigating. This undoubtedly allows the controller to obtain a better performance in highly dynamic environments The purpose of this article template is to serve as a model for a typical article for publication in the JBSMSE Journal of the Brazilian Society of Mechanical Sciences and Engineering. For submission purpose see Submission and Format session below. This abstract should, in no more than 200 words, describe the objectives, methodology used and main conclusions. It should not contain formulae or mathematical deductions.
Keywords: keyword 1, keyword 2, keyword 3, keyword 4, keyword 5
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Introduction
The introduction should contain information intended for all readers of the journal, not just specialists in its area. It should describe the problem statement, its relevance, significant results and conclusions from prior work and objectives of the present work.
Nomenclature
A = total frontal area of the air flow, area, m2
b = pin height, m
c = specific heat, J/(kg K) and parameter defined by Eq. (10), dimensionless
D = pin diameter, diameter, m
f = friction factor in the pinned annulus, friction factor, dimensionless
H = annular opening, m
h = average heat transfer coefficient of air, average heat transfer coefficient, W/(m2 K)
K = loss coefficient per transversal row of pins, dimensionless
k = material thermal conductivity of pin and tube, thermal conductivity, W/(m K)
L = length of the pinned test section, annulus length, m
m = integer variable, dimensionless
= mass flow rate, kg/s
N = number of pins in a cross-section, number of transversal rows, dimensionless
n = number of data runs of a sequence of runs, dimensionless
Nu = average Nusselt number of air, average Nusselt number, dimensionless
Pr = air Prandtl number, Prandtl number, dimensionless
Q = heat transfer rate, W
Rk = wall heat transfer resistance (wall thermal resistance), (m2 K)/W
Re = Reynolds number of the air flow, Reynolds number, dimensionless
S = pin pitch, m
T = absolute temperature, K
t = tube thickness, m
U = overall heat transfer coefficient, W/(m2 K)
Greek Symbols
DP = pressure drop, Pa
DTlog = logarithmic mean temperature difference, K
g = angle between two adjacent pins in the same cross-section, deg.
h = pin efficiency, pinned region efficiency, dimensionless
m = air dynamic viscosity, dynamic viscosity, kg/(m s)
r = air density, kg/m3
Subscripts
a relative to air
e relative to exit
f relative to pin fin
g relative to any fluid
h relative to the hydraulic diameter
i relative to inlet
k relative to wall thermal resistance
L relative to the number of transversal rows or to longitudinal pitch
log relative to logarithmic mean temperature difference
p relative to constant pressure, heat transfer area of the primary surface or to the pins
s relative to the smooth annulus
T relative to the numbers of pins in a same cross-section or to transversal pitch
t relative to total
w relative to water
1 relative to the internal diameter of the internal tube
2 relative to the external diameter of the internal tube
3 relative to the internal diameter of the external tube
Scope and Policy
The purpose of the JBSMSE Journal of the Brazilian Society of Mechanical Sciences and Engineering is to publish articles of permanent interest dealing with research, development and design related to science and technology in Mechanical Sciences and Engineering, encompassing interfaces with other branches of Engineering, as well as with Physics and Applied Mathematics.
The Journal publishes full-length articles, review articles, book reviews and letters to the Editor. Authors must agree not to publish elsewhere an article submitted and accepted by the Journal. Articles derived from partial results previously published in proceedings of conferences can also be considered for publication; the event should be cited as a footnote on the title page. A copy of the reviews by the conference referees should be included. Review articles should constitute a critical appraisal of the published information.
The decision of acceptance for publication lies with the Editors and is based on the recommendations of at least two ad hoc reviewers and, if necessary, a member of the Editorial Board.
Submission
Manuscripts and correspondence should be sent to the Editor that will be assign an Associate Editor whose area most closely matches that of the article.
Editor-in-Chief:
Prof. Paulo E. Miyagi – Departamento de Engenharia Mecatrônica e de Sistemas Mecânicos, Escola Politécnica da Universidade de São Paulo. CEP 05508-030 São Paulo, SP, Brazil. Phone:: +55-11-30915580, fax: +55-11-30915461, e-mail:
Authors are requested to send a copy of the article in electronic (.pdf) format by e-mail to the Editor-in-Chief. It is imperative that the electronic file contains all figures and mathematical equations appearing in the article.
Manuscripts should be submitted only in English.
A manuscript submitted for publication should be accompanied by a message containing the agreement of Journal rules, the Authors full name of the Author for contact, institution address, phone number, e-mail address and, if the Authors so wish, the names of up to five (5) possible referees, with respective addresses.
Format
Manuscripts should begin with the Title, Authors’ names and addresses followed by an Abstract and from three to five Keywords. The manuscript should not contain the. The Abstract should state the objectives, methodology used and main conclusions, in no more than 200 words.
In research articles sufficient information should be provided in the text, or by referring to articles in generally available Journals, to permit the work to be repeated.
The article must begin with an Introduction that is written for the general reader of the Journal, not for the specialist. This section should describe the problem statement, its relevance, significant results and conclusions from prior work, and objectives of the present work.
Uncertainties should be specified for experimental and numerical results.
All symbols should be defined in the text. A separate nomenclature section should list, in alphabetical order, the symbols used and their definitions. The Greek symbols follow the English symbols, and are followed by the subscripts and superscripts. Each dimensional symbol must have SI (metric) units mentioned; in addition, English units may be included parenthetically. Dimensionless groups and coefficients must be so defined and indicated.
Mathematical Equations
Equations that extend beyond the text width should be restated to go in two or more lines, as necessary to fit within the page width.
Fractional powers should be used instead of root signs.
A slash (/) should be used instead of a horizontal line for fractions, whenever possible; for example, use 2/3 for two-thirds.
Mathematical expressions should not be introduced along the text itself, as part of a sentence line, but typed on individual lines.
Numbers that identify mathematical expressions should be enclosed in parenthesis. Refer to equations in the text as “ Eq.(1)” or, if at the beginning of a sentence, as “ Equation (1)”.
Vectors should be typed boldface. Do not use arrows, wavy-line underscoring, etc.
(1)
(2)
Figures and Tables
Figures and Tables should be referred in consecutive Arabic numerals. They should have a caption and be placed as close as possible to their first reference in the text. Refer to figures in the text with the abbreviation “Fig. 1”, except at the beginning of a sentence, where “ Figure 1” should be used.
The figures presenting technical data/results should have a boundary on all four sides, with scale indicators (tick marks) on all sides.
The legend for the data symbols should be put inside the figure, as well as the labels for each curve. Lettering should be large enough to be clearly legible (1.5-2.0 mm).
All figures and tables must be in black and white.
Table 1. Characteristics of the Different Surfaces and Basic Experimental Conditions.
Surface / k(mm) / l
(mm) / x
(m) / U1
(m/s) / II§ / cf
( 103) / d
(mm) / U+ / R
mesh screen (wire dia.=0.69 mm) / 1.38 / 3.18 / 2.46 / 20 / 0.70 / 5.4 / 75 / 11.0 / 12800
Circular rods (dia.= 1.60 mm) / 1.60 / 6.4 / 2.03 / 7 / 0.83 / 6.3 / 74 / 11.4 / 4810
Smooth / - / - / 4.25 / 25 / 0.68 / 2.3 / 70 / 0 / 12570
is the streamwise wavelength for the mesh and the rods
refers to the measurement location
§ Coles' wake function parameter
Figure 2. Mean velocity distributions normalized using wall variables. , smooth wall (R =12570); , mesh roughness (R=8000); , rod roughness (R=12000); , DNS smooth (Spalart, 1988; R =1410). Unless noted, the same symbols are used in subsequent figures.
References
References should be cited in the text by giving the last name of the author(s) and the year of publication. Either use “Recent work (Smith and Farias, 2005) or “ Recently Smith and Farias (2005). With four (4) or more names, use the form “ Smith et al. (2005)”. If two or more references would have the same identification, distinguish them by appending “a”, “b”, etc., to the year of publication.
Acceptable references include journal articles, numbered papers, dissertations, thesis, published conference proceedings, preprints from conferences, books, submitted articles, if the journal is identified, and private communications.
References should be listed in alphabetical order, according to the last name of the first author, at the end of the article. Some sample references follow:
Bordalo, S.N., Ferziger, J.H. and Kline, S.J.,1989, “The Development of Zonal Models for Turbulence”, Proceedings of the 10th Brazilian Congress of Mechanical Engineering, Vol.1, Rio de Janeiro, Brazil, pp. 41-44.
Coimbra, A.L., 1978, ”Lessons of Continuum Mechanics”, Ed. Edgard Blücher, Sao Paulo, Brazil, 428 p.
Clark, J.A.,1986, Private Communication, University of Michigan, Ann Harbor.
Silva, L.H.M.,1988, ”New Integral Formulation for Problems in Mechanics” (In Portuguese), Ph.D. Thesis, Federal University of Santa Catarina, Florianópolis, S.C., Brazil, 223 p.
Soviero, P.A.O. and Lavagna, L.G.M.,1997, “A Numerical Model for Thin Airfoils in Unsteady Motion”, Journal of the Brazilian Soc. Mechanical Sciences, Vol.19, No. 3, pp. 332-340.
Sparrow, E.M., 1980a, ”Forced Convection Heat Transfer in a Duct Having Spanwise-Periodic Rectangular Protuberances”, Numerical Heat Transfer, Vol.3, pp. 149-167.
Sparrow, E.M., 1980b, ”Fluid-to-Fluid Conjugate Heat Transfer for a Vertical Pipe-Internal and External Natural Convection”, ASME Journal of Heat Transfer, Vol.102, pp. 402-407.
Final Version of the Manuscript
Upon notification of acceptance, Authors should submit by e-mail the final version of the final manuscript in accordance with the current template, in Windows or Macintosh’s Microsoft Word, thus avoiding retyping, with subsequent reduction of errors.
General Information
The JBSMSE Journal of the Brazilian Society of Mechanical Sciences and Engineering (ISSN 1678-5878) is published quarterly and owned by ABCM The Brazilian Society of Mechanical Sciences and Engineering, Av. Rio Branco, 124, 14o Andar, CEP 20040-001, Rio de Janeiro, RJ, Brazil, telephone +55 (21) 2221 0438, and is distributed freely to members. Rate for 2006 is US$320.00 for institutions and US$120.00 to individuals. Issues are airmail shipped. All subscriptions are payable in advance and entered on an annual basis.
Copyright Ó2006 by ABCM The Brazilian Society of Mechanical Sciences and Engineering. Printed in Brazil. Authorization to photocopy articles may be granted by the ABCM The Brazilian Society of Mechanical Sciences and Engineering provided the material is used on a personal basis only. The Society does not consent copying for general distribution, promotion, for creating a new work or for resale. Permission to photocopy articles must be requested to the Society’s main office.
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First Author et al.: Article Template (insert the paper’s title here)