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    Video images and undulatory movement equation of pangasius sanitwongsei's caudal fin of steady swimming fish

    , Article International Journal of Design and Nature and Ecodynamics ; Vol. 9, issue. 2 , 2014 , pp. 95-108 ; ISSN: 1755-7445 Vaghefi, A. S ; Abbaspour, M ; Sharif University of Technology
    Abstract
    Experimental hydrodynamics imaging of four Pangasius sanitwongsei were considered. A quantitative characterization of caudal fin is presented in this article. Steady swimming of four P. sanitwongsei with different total length was studied experimentally and taped by high-speed digital video, and undulatory movement of each fish at different velocity was revealed. The pattern of body undulatory movement of the fish was drawn from the video images. Three main factors that determine the fish swimming behavior are Reynolds number, Strouhal number and shape. In this study, Lf/L was chosen as a characteristic of shape, where Lf was the distance from the start of the head to the end of the head.... 

    Numerical investigation of the forward and backward travelling waves through an undulating propulsor: performance and wake pattern

    , Article Ships and Offshore Structures ; Apr , 2015 ; 17445302 (ISSN) Ebrahimi, M ; Abbaspour, M ; Sharif University of Technology
    Taylor and Francis Ltd  2015
    Abstract
    Recently, the mechanisms of natural undulatory locomotion of aquatic animal swimming have become one of the most significant issues for the researchers, swimmers and engineers. This study aims to elucidate and compare the propulsive vortical signature and performance of backward (negative undulation) and forward (positive undulation) travelling waves through a typical fishlike propulsor by a systematic numerical study. The numerical approach uses a pressure-based finite volume method solver to solve Navier–Stokes equations in an arbitrary Lagrangian–Eulerian framework domain containing a two-dimensional NACA 0012 foil moving with prescribed kinematics. Some of the important findings are: (1)... 

    A comparative numerical study on the performances and vortical patterns of two bioinspired oscillatory mechanisms: Undulating and pure heaving

    , Article Applied Bionics and Biomechanics ; Volume 2015 , 2015 ; 11762322 (ISSN) Ebrahimi, M ; Abbaspour, M ; Sharif University of Technology
    IOS Press  2015
    Abstract
    The hydrodynamics and energetics of bioinspired oscillating mechanisms have received significant attentions by engineers and biologists to develop the underwater and air vehicles. Undulating and pure heaving (or plunging) motions are two significant mechanisms which are utilized in nature to provide propulsive, maneuvering, and stabilization forces.This study aims to elucidate and compare the propulsive vortical signature and performance of these two important natural mechanisms through a systematic numerical study. Navier-Stokes equations are solved, by a pressure-based finite volume method solver, in an arbitrary Lagrangian- Eulerian (ALE) framework domain containing a 2D NACA0012 foil... 

    Numerical investigation of the forward and backward travelling waves through an undulating propulsor: performance and wake pattern

    , Article Ships and Offshore Structures ; Volume 11, Issue 5 , 2016 , Pages 517-539 ; 17445302 (ISSN) Ebrahimi, M ; Abbaspour, M ; Sharif University of Technology
    Taylor and Francis Ltd  2016
    Abstract
    Recently, the mechanisms of natural undulatory locomotion of aquatic animal swimming have become one of the most significant issues for the researchers, swimmers and engineers. This study aims to elucidate and compare the propulsive vortical signature and performance of backward (negative undulation) and forward (positive undulation) travelling waves through a typical fishlike propulsor by a systematic numerical study. The numerical approach uses a pressure-based finite volume method solver to solve Navier–Stokes equations in an arbitrary Lagrangian–Eulerian framework domain containing a two-dimensional NACA 0012 foil moving with prescribed kinematics. Some of the important findings are: (1)... 

    Modelling and economic evaluation of pressure-retarded osmosis power plant case study: Iran

    , Article International Journal of Ambient Energy ; 2017 , Pages 1-13 ; 01430750 (ISSN) Ansari, A ; Abbaspour, M ; Sharif University of Technology
    Abstract
    In recent years, a growing interest in investigation of new energies has been observed. Pressure-retarded osmosis (PRO) could be a feasible source of renewable energy. This study aims to present a model based on the present technology of PRO power plant components for design and economic evaluation of a PRO power plant, and to investigate case studies in order to demonstrate how each main component of a PRO power plant affects the economic evaluation. Therefore, all the mechanisms including intake and outfall systems, pre-treatment system, membrane system, and transportation and generation systems are explicated and meant to present the capability of the model to design the PRO power plant.... 

    Numerical study of propulsion performance in swimming fish using boundary element method

    , Article Journal of the Brazilian Society of Mechanical Sciences and Engineering ; Volume 39, Issue 2 , 2017 , Pages 443-455 ; 16785878 (ISSN) Najafi, S ; Abbaspour, M ; Sharif University of Technology
    Springer Verlag  2017
    Abstract
    In this paper, hydrodynamic simulation of fish-like swimming for two types of aquatic animals including tuna fish and giant danio is presented. We employ an unsteady three-dimensional inviscid boundary element method including time stepping algorithm to capture the wake sheet and flow features around swimming fish in a straight course. At each time step, an unsteady Bernoulli equation was used to find the pressure distribution and thrust generated by the animal. To couple fluid solver with kinematic equations of flexible body, undulating motions of backbone were defined using a prescribed continuous function. Although the flexible motion mechanism controls the fish swimming but no structural... 

    Experimental study on gyroscopic effect of rotating rotor and wind heading angle on floating wind turbine responses

    , Article International Journal of Environmental Science and Technology ; Volume 15, Issue 12 , 2018 , Pages 2531-2544 ; 17351472 (ISSN) Bahramiasl, S ; Abbaspour, M ; Karimirad, M ; Sharif University of Technology
    Abstract
    Limited fossil resources, daily increasing rate of demand for energy and the environmental pollution fact have made people revert to renewable sources of energy as a solution. One type of renewable energy is offshore wind energy which has high potential without any sound and visual noises. Recently, a lot of researchers have carried out on the issue of offshore wind turbine. Because of incapability of most of software programs to simulate gyroscopic effect of rotating rotors, in this articles a significant effort has been made to fabricate and test an offshore wind turbine under different rotor rotation velocities and different heading angle of wind so as to obtain the effects of these... 

    Harmful algal blooms (red tide): a review of causes, impacts and approaches to monitoring and prediction

    , Article International Journal of Environmental Science and Technology ; Volume 16, Issue 3 , 2019 , Pages 1789-1806 ; 17351472 (ISSN) Zohdi, E ; Abbaspour, M ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2019
    Abstract
    Red tide, an impermanent natural phenomenon including harmful algal blooms, causes changing the color of the sea generally to red or almost brown, and has a serious impact on environment along the coast and aquatic ecosystem. Due to recent extensive steady harmful algal blooms events that cause adverse impacts on human healthsome, aquaculture and tourism industry, and the entire economy of the coastal region, the need of society for realizing these phenomena is much greater than the past. In the recent decades, consideration of algal blooms and determination of bloom-former species and fundamental researches about dynamics of blooms are increased worldwide. Development in technology has... 

    Modelling and economic evaluation of pressure-retarded osmosis power plant case study: Iran

    , Article International Journal of Ambient Energy ; Volume 40, Issue 1 , 2019 , Pages 69-81 ; 01430750 (ISSN) Ansari, A ; Abbaspour, M ; Sharif University of Technology
    Taylor and Francis Ltd  2019
    Abstract
    In recent years, a growing interest in investigation of new energies has been observed. Pressure-retarded osmosis (PRO) could be a feasible source of renewable energy. This study aims to present a model based on the present technology of PRO power plant components for design and economic evaluation of a PRO power plant, and to investigate case studies in order to demonstrate how each main component of a PRO power plant affects the economic evaluation. Therefore, all the mechanisms including intake and outfall systems, pre-treatment system, membrane system, and transportation and generation systems are explicated and meant to present the capability of the model to design the PRO power plant.... 

    Enhancing the roll dynamics of an AUV by contra-rotating-propellers

    , Article Ships and Offshore Structures ; 2020 Ebrahimi, M ; Kamali, A ; Abbaspour, M ; Sharif University of Technology
    Taylor and Francis Ltd  2020
    Abstract
    Roll control of the Autonomous Underwater Vehicles (AUVs) is a significant issue in the current field of research for many researchers in the subject of AUV control system designation. Especially at higher speeds, the roll angle generated by a single rotating propeller or other external disturbances can considerably influence the whole dynamics and therefore the operation of the vehicle. In this paper, the utilisation of a system of contra-rotating-propellers (CRP) to enhance the roll dynamics of an AUV is evaluated by developing a six-degrees-of-freedom (6DOF) dynamics and control systems’ simulator. The results show that: 1. The single propeller system can cause roll angle deflections... 

    Enhancing the roll dynamics of an AUV by contra-rotating-propellers

    , Article Ships and Offshore Structures ; Volume 16, Issue 7 , 2021 , Pages 787-796 ; 17445302 (ISSN) Ebrahimi, M ; Kamali, A ; Abbaspour, M ; Sharif University of Technology
    Taylor and Francis Ltd  2021
    Abstract
    Roll control of the Autonomous Underwater Vehicles (AUVs) is a significant issue in the current field of research for many researchers in the subject of AUV control system designation. Especially at higher speeds, the roll angle generated by a single rotating propeller or other external disturbances can considerably influence the whole dynamics and therefore the operation of the vehicle. In this paper, the utilisation of a system of contra-rotating-propellers (CRP) to enhance the roll dynamics of an AUV is evaluated by developing a six-degrees-of-freedom (6DOF) dynamics and control systems’ simulator. The results show that: 1. The single propeller system can cause roll angle deflections... 

    Numerical study to evaluate the important parameters affecting the hydrodynamic performance of manta ray's in flapping motion

    , Article Applied Ocean Research ; Volume 109 , 2021 ; 01411187 (ISSN) Safari, H ; Abbaspour, M ; Darbandi, M ; Sharif University of Technology
    Elsevier Ltd  2021
    Abstract
    Manta ray swimming or bio-inspiration propulsion system, as a special type of marine propulsion system, is used for submersible vehicles that require high-speed maneuverability and stability, such as glider and AUV. In a manta ray swimming, the thrust force is generated by a couple of undulation and oscillation of wing, so that the direction of undulation wave and oscillation is upright and perpendicular to the direction of thrust force, respectively. It is possible to combine these two movement modes (flapping motion) on the three-dimensional model without considering the effects of wing twisting and flexibility to simplify and better understand the physical behaviors or special study of... 

    Multi criteria site selection model for wind-compressed air energy storage power plants in Iran

    , Article Renewable and Sustainable Energy Reviews ; Vol. 32 , April , 2014 , pp. 579-590 ; ISSN: 13640321 Satkin, M ; Noorollahi, Y ; Abbaspour, M ; Yousefi, H ; Sharif University of Technology
    Abstract
    In this research, a site selection method for wind-compressed air energy storage (wind-CAES) power plants was developed and Iran was selected as a case study for modeling. The parameters delineated criteria for potential wind development localities for wind-CAES power plant sites. One important consequence of this research was the identification of the wind energy potential for wind-CAES sites. The theoretical wind energy potential of Iran of greater than 50 W/m2 was identified from a wind atlas of Iran. The model produced factor maps by considering the boundary conditions of the input data and created geo-databases from the outputs maps. The main factor maps were electrical grids and... 

    The design of an estimation model for environmental liability insurance (ELIS)

    , Article International Journal of Environmental Research ; Vol. 8, Issue. 1 , 2014 , Pages 193-204 ; ISSN: 17356865 MirzaEbrahim Tehrani, M ; Abbaspour, M ; Nouri, J ; Mazloomi, N ; Sharif University of Technology
    Abstract
    Pricing for an insurance policy can be described as the process of calculation of expected compensation to be paid to property losers as well as associated costs of potential risks. Loss forecast is accurate if the risks will be identified appropriately in order to calculate the frequency and expected severity of losses.This is particularly important about environmental risks since most of them appear in the long run. Environmental risk assessment model is both able to estimate the environmental liability premium for environmental pollution and degradation, and it can play a valuable role in promoting this industry. ELIS (Environmental Liability Insurance) software calculates the... 

    Dynamic behavior of a tension leg platform offshore wind turbine under environmental loads

    , Article Scientia Iranica ; Vol. 21, issue. 3 , 2014 , pp. 480-491 ; ISSN : 1026-3098 Ebrahimi, A ; Abbaspour, M ; Nasiri, R. M ; Sharif University of Technology
    Abstract
    In order to evaluate the dynamic behavior of floating offshore wind turbines, the authors consider two approaches. A numerical method is used to investigate Tension Leg Platform (TLP) offshore wind turbine response behavior under a parked condition. This code considers nonlinearities due to changes in the tension of tethers. The off-diagonal components of stiffness, damping and mass matrices are considered to calculate coupling. This code solves the nonlinear equation of motion at each time step. However, in order to validate the data generated by the code, a scaled-down model was fully tested in the marine laboratory. The importance of these series of experiments is due to the fact that... 

    Effect of decision variables in the steam section for the exergoeconomic analysis of TCCGT power plant: A case study

    , Article Energy and Environment ; Vol. 25, issue. 8 , 2014 , p. 1381-1404 Abdalisousan, A ; Fani, M ; Farhanieh, B ; Abbaspour, M ; Sharif University of Technology
    Abstract
    In advanced combined-cycle power plants, significant improvements in the thermodynamic performance are mainly achieved by the development of more efficient gas-turbine systems. This paper evaluates the effect of selected decision variables in the steam system for optimization of Thermal Combined Cycle Gas Turbine (TCCGT) power plant using an iterative exergoeconomic. The design variables were the thermodynamic parameters that establish the configuration both of the steam and gas systems. The design data of an existing plant (Damavand power plant in Tehran-Iran) is used. Two different objective functions are proposed: one minimizes the total cost of production per unit of output, and the... 

    Investigating the impacts of global environmental evolutions on long-term planning of natural resources in Iran

    , Article International Journal of Environmental Research ; Volume 7, Issue 3 , 2013 , Pages 561-568 ; 17356865 (ISSN) Javaherian, Z ; Maknoon, R ; Abbaspour, M ; Moharamnejad, N ; Sharif University of Technology
    2013
    Abstract
    The main objective of the current study is to investigate the impacts of environmental evolutions at global scale on Iran's environmental planning. Thereby, all political movements towards solving environmental issues in Iran were accurately reviewed to find out the impressibility of the events by the global environmental evolutions. The findings indicated that Iran has joined the conventions and protocols with a time lag. During the period 1948-1993, the mean time lag between holding an international convention until its approval in Iran was eleven years while from 1994 to 2007, the average lag time was shortened to four years. As the results show, attention to environmental issues was... 

    What is energy efficiency and emission reduction potential in the Iranian petrochemical industry?

    , Article International Journal of Greenhouse Gas Control ; Volume 12 , 2013 , Pages 460-471 ; 17505836 (ISSN) Mohammadi, A ; Soltanieh, M ; Abbaspour, M ; Atabi, F ; Sharif University of Technology
    2013
    Abstract
    In this study, the prospects of energy efficiency potential, clean development mechanism (CDM) and carbon income up to and beyond 2012 are investigated in the petrochemical industries of Iran as a major oil-producing country. This paper is to address four questions of: (1) the GHGs emission in Iranian petrochemical complexes, (2) the most energy-consuming processes, (3) units with the highest energy efficiency potentials and (4) potentials of CDM or similar carbon projects based on post-2012 scenarios. The petrochemical processes are investigated in two categories of non-polymeric and polymeric productions. Based on capital expenditure, economic saving, simple payback period, CO2 equivalent... 

    Air Quality Risk Index (AQRI) and its application for a megacity

    , Article International Journal of Environmental Science and Technology ; Volume 12, Issue 12 , December , 2015 , Pages 3773-3780 ; 17351472 (ISSN) Ahmadi, A ; Abbaspour, M ; Arjmandi, R ; Abedi, Z ; Sharif University of Technology
    Center for Environmental and Energy Research and Studies  2015
    Abstract
    Urban air quality is a major concern throughout the world. The concentration of human activities in a relatively small area puts enormous pressure on urban systems and has led to numerous environmental problems which have created major problems for urban air quality management. The complex nature of air pollution, especially with respect to health impacts in urban areas, has prompted attempts to define the so-called indicators that condense and simplify the available monitoring data to make them suitable for public reporting and decision makers. Several concepts and indicators exist to measure and rank urban areas in terms of their infrastructural, socioeconomic and environment-related... 

    Multi-objective thermoeconomic optimisation for combined-cycle power plant using particle swarm optimisation and compared with two approaches: An application

    , Article International Journal of Exergy ; Volume 16, Issue 4 , 2015 , Pages 430-463 ; 17428297 (ISSN) Abdalisousan, A ; Fani, M ; Farhanieh, B ; Abbaspour, M ; Sharif University of Technology
    Inderscience Enterprises Ltd  2015
    Abstract
    This paper shows a new possible way with particle swarm optimisation (PSO) to achieve an exergoeconomic optimisation of combinedcycle power plants. The optimisation has been done using a classic exergoeconomic and genetic algorithm, and the effects of using three methods are investigated and compared. The design data of an existing plant is used for the present analysis. Two different objective functions are proposed: One minimises the total cost of production per unit of output, and maximises the total exergetic efficiency. The analysis shows that the total cost of production per unit of output is 2%, 3%and 5% lower and exergy efficiency is 4%, 8% and 6% higher with respect to the base case...