The Experts below are selected from a list of 33882 Experts worldwide ranked by ideXlab platform
Reza Rahgozar - One of the best experts on this subject based on the ideXlab platform.
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Seismic Performance of Outrigger-Braced System Based on Finite Element and Component-Mode Synthesis Methods
Iranian Journal of Science and Technology Transactions of Civil Engineering, 2019Co-Authors: Reihaneh Tavakoli, Reza Kamgar, Reza RahgozarAbstract:Determining the Optimum Location of outrigger-belt truss system is of the most important challenges in tall structures. In this paper, two numerical methods, finite element method (FEM) and component-mode synthesis (CMS), are evaluated to determine the seismic performance of two buildings with different heights: one with 20 stories and the other with 30 stories. To find the Optimum Location of the outrigger, seismic performance of 2D outrigger-braced buildings in terms of inter-story drift ratio, roof displacement, base shear, and base moment is investigated. It is concluded that CMS as a model reduction method is very effective and useful in reducing the required analysis time as well as having good concordance with FEM results. The seismic responses of the two buildings change significantly as the outrigger Location changes from the first to the last story. The accuracy of the results is verified through the OpenSees program. Results show that the component-mode synthesis method is able to reduce the analysis time significantly, and also the efficiency and impotence of this method are more obvious as degrees of freedom are increased. In addition, placing the outrigger system at 0.6 H to 0.8 H of the total height of the building improves the seismic performance of the structure.
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Determination of Optimum Location for flexible outrigger systems in tall buildings with constant cross section consisting of framed tube, shear core, belt truss and outrigger system using energy method
International Journal of Steel Structures, 2017Co-Authors: Reza Kamgar, Reza RahgozarAbstract:In this paper, based on maximizing the outrigger-belt truss system’s strain energy, a methodology for determining the Optimum Location of a flexible outrigger system is presented. Tall building structures with combined systems of framed tube, shear core, belt truss and outrigger system are modeled using continuum approach. In this approach, the framed tube system is modeled as a cantilevered beam with box cross section. The effect of outrigger and shear core systems on framed tube’s response under lateral loading is modeled by a rotational spring placed at the Location of belt truss and outrigger system. Optimum Location of this spring is obtained when energy absorbed by the spring is maximized. For this purpose, first derivative of the energy equation with respect to spring Location as measured from base of the structure, is set to zero. Optimum Location for outrigger and belt truss system is calculated for three types of lateral loadings, i.e. uniformly and triangularly distributed loads along structure’s height, and concentrated load at top of the structure. Accuracy of the proposed method is verified through numerical examples. The results show that the proposed method is reasonably accurate. In addition, for different stiffness of shear core and outrigger system, several figures are presented that can be used to determine the Optimum Location of belt truss and outrigger system.
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determination of Optimum Location for flexible outrigger systems in non unifrom tall buildings using energy method
Iran University of Science & Technology, 2015Co-Authors: Reza Kamgar, Reza RahgozarAbstract:In this paper, based on maximizing the outrigger-belt truss system’s strain energy, a methodology for determining the Optimum Location of a flexible outrigger system is presented. Tall building structures with combined systems of framed tube, shear core, belt truss and outrigger system are modeled using continuum approach. In this approach, the framed tube system is modeled as a cantilevered beam with box cross section. The effect of outrigger and shear core systems on framed tube’s response under lateral loading is modeled by a rotational spring placed at the Location of belt truss and outrigger system. Optimum Location of this spring is obtained when energy absorbed by the spring is maximized. For this purpose, first derivative of the energy equation with respect to spring Location as measured from base of the structure, is set to zero. Optimum Location for outrigger and belt truss system is calculated for three types of lateral loadings, i.e. uniformly and triangularly distributed loads along structure’s height, and concentrated load at top of the structure. Accuracy of the proposed method is verified through numerical examples. The results show that the proposed method is reasonably accurate. In addition, for different stiffness of shear core and outrigger system, several figures are presented that can be used to determine the Optimum Location of belt truss and outrigger system.
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Optimum Location of outrigger belt truss in tall buildings based on maximization of the belt truss strain energy
International Journal of Engineering, 2013Co-Authors: M Jahanshahi, Reza RahgozarAbstract:A B S T R A C T In this paper, based on maximizing the outrigger-belt truss system’s strain energy, a methodology for determining the Optimum Location of an outrigger-belt truss system is presented. Tall building structures with combined systems of framed tube, shear core and outrigger-belt truss system are modeled using continuum approach. In this approach, the framed tube system is modeled as a cantilevered beam with box cross section. The effect of outrigger-belt truss and shear core system on framed tube’s response under lateral loading is modeled by a rotational spring at the outrigger-belt truss Location. Optimum Location of this spring is obtained when energy absorbed by the spring is maximized. For this purpose, first derivative of the energy equation with respect to spring Location as measured from base of the structure, is set to zero. Optimum Location for outrigger-belt truss system is calculated for three types of lateral loadings, i.e. uniformly and triangularly distributed loads along structure’s height, and concentrated load at top of the structure. Accuracy of the proposed method is verified through numerical examples. The results show that the proposed method is reasonably accurate.
Saeed Moghadam Deymeh - One of the best experts on this subject based on the ideXlab platform.
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determination of Optimum Location and tilt angle of solar collector on the roof of buildings with regard to shadow of adjacent neighbors
Sustainable Cities and Society, 2015Co-Authors: Hamid Moghadam, Saeed Moghadam DeymehAbstract:Abstract Solar systems have been widely used in recent years to supply some portion of buildings energy demands. Solar cells and flat collectors usually installed on the roof of buildings to keep away from the shade effects. Moreover, those must be installed incline at Optimum angle to maximize the receiving energy. Determination of the Optimum tilt angle of solar collectors is the subject of many investigations. These studies had supposed that, there is no barrier between the sun and collectors from sunrise since to sunset. In fact, any building may be surrounded by taller neighboring buildings. In these conditions, previous studies could not estimate the Optimum tilt angle, truly. In addition, there are Locations on the roofs which have more sunny time. These areas are more suitable for installation of collectors. Determination of Optimum Location and Optimum tilt angle of solar collectors on the roof, with respect to the shadow of adjacent buildings is the main aim of this paper. Obtained results revealed that for earth's northern hemisphere, solar collectors should be installed on the southern edge of the roof as far as possible away from the taller neighboring building. If the roof is surrounded by two taller buildings, solar collector should be installed approximately on the center of the southern edge. Accordingly, received energy form the direct solar radiation on the Optimum Location could be increases more over the 15%. In addition, it was found that shade has minor effects on the Optimum tilt angle for the parts of the roof near to the taller neighbor. In contrast, there is a considerable change of Optimum tilt angle (up to 10°) for the farther regions form the taller neighbor.
Kiran Shahapurkar - One of the best experts on this subject based on the ideXlab platform.
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Optimum Location and influence of tilt angle on performance of solar PV panels
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: T. M. Yunus Khan, Manzoore Elahi. M. Soudagar, Mithun Kanchan, Naveed Akram, Suresh D. Mane, Nagaraj R. Banapurmath, Asif Afzal, Kiran ShahapurkarAbstract:With the growing demand of economically feasible, clean, and renewable energy, the use of solar photovoltaic (PV) systems is increasing. The PV panel performance to generate electrical energy depends on many factors among which tilt angle is also a crucial one. Among hundreds of research work performed pertinent to solar PV panels performance, this work critically reviews the role of tilt angles and particularly locating the Optimum tilt angle using different methods. The past data collected for analysis can be categorized mainly into mathematical model based, experimental based, simulation based, or combination of any of these. Single-axis tracking, dual-axis tracking, simple glass cover, hydrophobic glass cover, soiled glass, clean glass, partial shadow, use of phase-change material, computational fluid dynamic analysis, etc., are the novel methods found in the literature for analysis and locating the Optimum tilt angle. For illustration purpose, few figures are provided in which the Optimum tilt angle obtained on monthly, seasonally, and annual basis is shown. Research works are growing in the field of computations and simulations using online software and codes. Pure mathematical-based calculations are also reported but the trend is to combine this method with the simulation method. As the PV panel performance is found to be affected by number of parameters, their consideration in any single study is not reported. In future, work is required to carry out the experiment or simulation considering the effect of soiling, glass material, temperature, and surrounding ambience on the Location of Optimum tilt angle. As a whole, the Optimum tilt angles reported for Locations exactly on the equator line, i.e., 0° latitude, ranges between − 2.5° and 2.5°, for Locations just above the equator line, i.e., latitude 2.6°–30° N ranges between 5° and 28°, for 40°–70° N, it is 29°–40°, and for 71°–90° N, it is 41°–45°. For Locations at 2.6°–30° S, Optimum tilt angles range between − 4° and − 32°, 30°–46° S, it is − 33° to − 36°, 47°–65° S, it is − 34° to − 50°, and for 66°–90° S it is − 51° to − 62°.
Hamid Moghadam - One of the best experts on this subject based on the ideXlab platform.
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determination of Optimum Location and tilt angle of solar collector on the roof of buildings with regard to shadow of adjacent neighbors
Sustainable Cities and Society, 2015Co-Authors: Hamid Moghadam, Saeed Moghadam DeymehAbstract:Abstract Solar systems have been widely used in recent years to supply some portion of buildings energy demands. Solar cells and flat collectors usually installed on the roof of buildings to keep away from the shade effects. Moreover, those must be installed incline at Optimum angle to maximize the receiving energy. Determination of the Optimum tilt angle of solar collectors is the subject of many investigations. These studies had supposed that, there is no barrier between the sun and collectors from sunrise since to sunset. In fact, any building may be surrounded by taller neighboring buildings. In these conditions, previous studies could not estimate the Optimum tilt angle, truly. In addition, there are Locations on the roofs which have more sunny time. These areas are more suitable for installation of collectors. Determination of Optimum Location and Optimum tilt angle of solar collectors on the roof, with respect to the shadow of adjacent buildings is the main aim of this paper. Obtained results revealed that for earth's northern hemisphere, solar collectors should be installed on the southern edge of the roof as far as possible away from the taller neighboring building. If the roof is surrounded by two taller buildings, solar collector should be installed approximately on the center of the southern edge. Accordingly, received energy form the direct solar radiation on the Optimum Location could be increases more over the 15%. In addition, it was found that shade has minor effects on the Optimum tilt angle for the parts of the roof near to the taller neighbor. In contrast, there is a considerable change of Optimum tilt angle (up to 10°) for the farther regions form the taller neighbor.
T. M. Yunus Khan - One of the best experts on this subject based on the ideXlab platform.
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Optimum Location and influence of tilt angle on performance of solar PV panels
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: T. M. Yunus Khan, Manzoore Elahi. M. Soudagar, Mithun Kanchan, Naveed Akram, Suresh D. Mane, Nagaraj R. Banapurmath, Asif Afzal, Kiran ShahapurkarAbstract:With the growing demand of economically feasible, clean, and renewable energy, the use of solar photovoltaic (PV) systems is increasing. The PV panel performance to generate electrical energy depends on many factors among which tilt angle is also a crucial one. Among hundreds of research work performed pertinent to solar PV panels performance, this work critically reviews the role of tilt angles and particularly locating the Optimum tilt angle using different methods. The past data collected for analysis can be categorized mainly into mathematical model based, experimental based, simulation based, or combination of any of these. Single-axis tracking, dual-axis tracking, simple glass cover, hydrophobic glass cover, soiled glass, clean glass, partial shadow, use of phase-change material, computational fluid dynamic analysis, etc., are the novel methods found in the literature for analysis and locating the Optimum tilt angle. For illustration purpose, few figures are provided in which the Optimum tilt angle obtained on monthly, seasonally, and annual basis is shown. Research works are growing in the field of computations and simulations using online software and codes. Pure mathematical-based calculations are also reported but the trend is to combine this method with the simulation method. As the PV panel performance is found to be affected by number of parameters, their consideration in any single study is not reported. In future, work is required to carry out the experiment or simulation considering the effect of soiling, glass material, temperature, and surrounding ambience on the Location of Optimum tilt angle. As a whole, the Optimum tilt angles reported for Locations exactly on the equator line, i.e., 0° latitude, ranges between − 2.5° and 2.5°, for Locations just above the equator line, i.e., latitude 2.6°–30° N ranges between 5° and 28°, for 40°–70° N, it is 29°–40°, and for 71°–90° N, it is 41°–45°. For Locations at 2.6°–30° S, Optimum tilt angles range between − 4° and − 32°, 30°–46° S, it is − 33° to − 36°, 47°–65° S, it is − 34° to − 50°, and for 66°–90° S it is − 51° to − 62°.
