VOLUME 7, ISSUE 4, 2016



Aims and Scope
Editorial Board

Volume 7, Issue 4, 2016, pp.i-viii. Download Full Text (PDF)

1. Computational Fluid Dynamics analysis applied to engineering and design of poultry farms

Eva H. Guerra-Galdo1, Fernando Estellés Barber1, Salvador Calvet Sanz1, P. Amparo López-Jiménez2

1 Institute of Animal Science and Technology, Universitat Politècnica de València. Camino de Vera s/n. 46022 Valencia, Spain.

2 Hydraulic and Environmental Engineering Department. Universitat Politècnica de València. Camino de Vera s/n. 46022 Valencia, Spain.

Abstract: The shape of a poultry building and the distribution of its elements (roof, windows distribution, and window opening) influence the velocity and temperature distribution inside the building and therefore the thermal comfort of the broilers. Considering these components, Computational Fluid Dynamics (CFD) was used to analyze the environmental conditions of 3 poultry buildings: tunnel (T), semi-tunnel (ST) and improved semi-tunnel (IST). These three buildings had the same dimensions but differed in the relative position of fans and windows. This study modelled the effect of different configurations of roof (flat or gable roof) and window design (with or without flap plate) on the distribution of temperature, air velocity and Index of Temperature and Velocity (ITV) at animal level (0.20 m above the ground). Simulations were conducted for summer and winter conditions. In summer conditions, configuration IST with gable roof without flap plate had lowest air velocity 0.72±0.27 m/s and average temperature (22.9±0.9ºC) whereas tunnel configuration with gable roof and flap plate had lowest ITV (22.94±1.30ºC on average). In winter conditions, IST configuration with flat roof had lowest average air velocity (0.24 m/s), whereas the highest temperature corresponded to semi-tunnel with gable roof without flap plate of the slot opening (19.35±2.67ºC). Finally, the lowest ITV corresponded to tunnel without flap plate and gable roof configuration (19.14±3.57ºC). According to the CFD simulations, in three configurations the variables analyzed were within the comfort ranges reported for animals inside buildings.

Volume 7, Issue 4, 2016, pp.269-282.

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2. Case study of building energy load calculations for a sustainable technology demonstration project

Kevin R. Anderson, Ian Villazana, Thomas Gross

Solar Thermal Alternative Renewable Energy Lab, Mechanical Engineering, California State Polytechnic University at Pomona, 3801 West Temple Ave, Pomona, CA, 91768, USA.

Abstract: The objective of this paper is to conduct an energy analysis of the Frontier Project using computer-based software and to verify results using load calculation spreadsheets. The Frontier Project is a demonstration of sustainable and renewable energy technologies [1]. The current paper serves to quantify the building energy demands by performing a building energy load calculation on the facility. This is meant to act as a case-study of how energy and the environment can be influenced by using and promoting the correct technologies. The computer-based software selected for use was eQUEST [7] version 3.65. The ASHRAE Bin Method was used to validate the eQUEST computer model. The methods are found to agree with 20% shown that the overall load is 20 tons or 70.34 kW for the 1759.2 m2 facility.

Volume 7, Issue 4, 2016, pp.283-290. Download Full Text Article (PDF)

3. Application of selected indices on outdoor thermal comfort assessment in Midwest Brazil

Julia R. Lucchese1,2, Larissa P. Mikuri2, Natacha V. S. de Freitas2, Wagner A. Andreasi1,2

1 Faculty of Engineering, Architecture and Urban Planning and Geography. Federal University of Mato Grosso do Sul (FAENG/UFMS). Campo Grande, Mato Grosso do Sul, 79070-900, Brazil.

2 Laboratory of Analysis and Development of Buildings. Federal University of Mato Grosso do Sul (LADE/UFMS). Campo Grande, Mato Grosso do Sul, 79070-900, Brazil.

Abstract: This paper presents the results of outdoor thermal comfort research conducted in a public square of Campo Grande (hot-humid climate) during hot and cold seasons. The objective is to compare the predictive ability of the following indices: Physiological Equivalent Temperature (PET), Universal Thermal Climate Index (UTCI), Perceived Equivalent Temperature (TEP), Sense of Thermal Comfort (YDS), and Predicted Mean Vote (PMV). To obtain necessary data, micrometeorological measurements and questionnaire surveys were performed simultaneously during field campaigns. We found that a purely physiological approach was insufficient in the assessment, as the selected indices did not efficiently predict the thermal sensation votes of the locals. PET and UTCI had relatively satisfactory performances, but regional calibration was necessary. Acquired subjective votes enabled the proposal of PET calibration (comfort range 21-27 °C PET). Based on the adjusted thermal scale (63% accuracy), discomfort hours were estimated. Results provided by this study can help landscape architects and urban planners define specific design guidelines for urban open spaces of Campo Grande.

Volume 7, Issue 4, 2016, pp.291-302. Download Full Text Article (PDF)

4. Numerical simulation and analyses for sinter cooling process with convective and radiative heat transfer

Xun Shen 1,2,3, Lingen Chen 1,2,3, Shaojun Xia 1,2,3, Fengrui Sun 1,2,3

1 Institute of Thermal Science and Power Engineering, Naval University of Engineering, Wuhan 430033, China.

2 Military Key Laboratory for Naval Ship Power Engineering, Naval University of Engineering, Wuhan 430033, China.

3 College of Power Engineering, Naval University of Engineering, Wuhan 430033, China.

Abstract: Based on the numerical heat transfer theory, a two-dimensional unsteady model for sinter cooling process is established by applying porous medium flow and heat transfer mechanism. The complex heat transfer process, including three modes of heat conduction inside the sinter ore particles, gas-solid convection and radiation in the trolley, is taken into account. By using the mass, momentum and energy conservation equations, the pressure field, temperature distribution and the temperature characteristic of outlet gas are obtained by the numerical simulation method. The effect of radiative heat transfer on the cooling process is analyzed.

Volume 7, Issue 4, 2016, pp.303-316. Download Full Text Article (PDF)

5. Investigation potential flow about swept back wing using panel method

WakkasAli Rasheed, NabeelAbdulhadiGhyadh, Sahib Shihab Ahmed

Department of Mechanical Engineering, Faculty of Engineering, Al-Kufa University, Ministry of Higher Education & Scientific Research, Iraq.

Abstract: In the present investigation Low order panel method with Dirichlet boundary condition conjugated with Kutta condition, was used to calculate pressure coefficients for potential flow about isolated swept back wings at different aspect ratios and different angles of attack. Also both local and total lift coefficients were calculated for the same wings, with detailed streamline behavior on both upper and lower surface. Constant strength quadrilateral doublet element and Constant strength quadrilateral source element were placed on each panel, except on wake sheet only constant strength quadrilateral doublets were placed to satisfy Kutta condition at trailing edge. A set of linear algebraic equations were established by setting inner potential equals to free stream potential. These equations were solved using Gauss-elimination to determine quadrilateral doublet singularity strength distribution. Finally finite difference formula was used to predict aerodynamic loads calculation.

Volume 7, Issue 4, 2016, pp.317-326. Download Full Text Article (PDF)

6. Estimation of real-sky daily solar irradiation case study: Braşov, Romania

Elena Eftimie

Department of Product Design, Mechatronics and Environment, Transilvania University of Braşov, Eroilor 29, 500036, Romania.

Abstract: The study presented by this paper is intended to estimate the daily solar irradiation under real-sky condition for Braşov (Romania) area. To this end, it is presented the methodology that was led to determine the estimation regressions of daily solar irradiation and the results of meteorological data sets processing. It is also performed an analysis of the variation of some climatic parameters specific to the analyzed area as, the sunshine fraction, the sky ratio and the Perez’s clearness index, in order to identify the possible sources of error and to assess their impact on accuracy of estimation models for daily solar irradiation. Special attention has been given to the analysis of statistical indicators that were the basis for performance analysis of the obtained models; focusing on optimizing the Pearson's coefficient, this paper presents the monthly regressions for two estimation models of daily global irradiance and corresponding to these, four estimation models of daily diffuse irradiation.

Volume 7, Issue 4, 2016, pp.327-346. Download Full Text Article (PDF)

7. Hydro, thermal and photovoltaic power plants: A comparison between electric power generation, environmental impacts and CO2 emissions in the Brazilian scenario

Juliana D’ Angela Mariano1, Francielle Rocha Santos1, Gabriel Wolanski Brito2, Jair Urbanetz Junior1, 3, Eloy Fassi Casagrande Junior1

1 Civil Engineering, Technological Federal University of Paraná, Curitiba, Brazil.

2 Technological Federal University of Paraná, Curitiba, Brazil.

3 Electrical Engineering, Technological Federal University of Paraná, Curitiba, Brazil.

Abstract: The challenge of sustainability is present in electricity generation. The sources should be renewable, and production should respect the environment and all forms of life. Being the main energy sources in Brazil, hydroelectric and thermal power plants have drawbacks when considering environmental impacts. In contrast, the use of photovoltaic energy is a sustainable alternative, pollution-free in its operating phase and with significantly less impact in its construction phase. The purpose of this article is to make a relation between the electricity generated by the hydroelectric Itaipu plant, the thermoelectric complex Jorge Lacerda, the Eletronuclear plant, and the analysis of a photovoltaic plant proposal for these three scenarios. The relation between the production of electricity in Itaipu, Jorge Lacerda, and Eletronuclear power plants, and the projected energy production of a photovoltaic plant for each scenario was obtained through calculations according to the area of ​​each plant, generating a comparison between the installed power of the referred plants, and the estimated installed capacity for the projected photovoltaic plant. The environmental impacts were assessed for the different scenarios, and CO2 emissions were quantified. The calculated results show that the installed power of the projected photovoltaic plant was significantly higher than the installed power of the existing plants. The photovoltaic plant’s capacity factor, for the proposed study, was of 15%, and the projected annual photovoltaic energy for the respective areas presented significantly higher values, ​​of approximately 330,180.40 TWh in comparison to Itaipu plant, while in comparison to Jorge Lacerda plant, for instance, it was of approximately 428,229.23 TWh, whereas to Eletronuclear it was 0.0288 TWh. The results of this study show that photovoltaic plants with equivalent areas of Itaipu and Jorge Lacerda power plants, could generate higher annual energy, nevertheless the same analyses to Eletronuclear power plant showed that the projection would not be viable.

Volume 7, Issue 4, 2016, pp.347-356. Download Full Text Article (PDF)