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water-distribution-systems
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Modeling and Simulating of Water Distribution in Different Layers of Direct Methanol Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor)
Abstract
A two-dimensional, two-phase, nonisothermal model was developed in this work to investigate the water transport characteristic and water distribution in a direct methanol fuel cell (DMFC). Emphasis is placed on exploring the water distribution in different layers of DMF. The water and methanol crossover through the membrane were considered with the effect of diffusion, electro-osmotic drag, and convection. Governing equations including the prton and electron transport, continuity, momentum, species transport for methanol, water, and gases species, and the auxiliary equations are coupled to determine the output parameters. These parameters are the concentration distribution of the species,...
Modeling and Simulation of Water Distribution in the Various Layers of Polymer Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor) ; Khorashe, Farhad (Supervisor)
Abstract
Fossil fuel are energy resources in decline. In recent years, fuel cell have become as a source of energy to replace conventional systems .Among the various types of fuel cells, PEMFCs (proton exchange membrane fuel cells) possess a series of highly advantageous features such as a low-operating temperature, sustained operation at high-current density, low weight, compactness, potential for low cost and volume, long stack life, fast start-ups and suitability for discontinuous operation. Water management is one of the most critical and challenging problems. There is a delicate balance between the membrane hydration and avoiding cathode from flooding. Cathode flooding occurs when the water...
Pressure - Leakage relation in urban water distribution systems
, Article Proceedings of the ASCE International Conference on Pipeline Engineering and Construction: New Pipeline Technologies, Security and Safety, Baltimore, MD, 13 June 2003 through 16 June 2003 ; Volume 1 , 2003 , Pages 304-312 ; 0784406901 (ISBN); 9780784406908 (ISBN) ; Ghazali, A. A ; Sharif University of Technology
American Society of Civil Engineers Texas Section
2003
Abstract
Due to increase of per capita water usage, water supply costs and population growth rate; optimal usages of available resources are vital. This is especially important in developing countries. If we add water resource deficits to the above problems, its importance duplicates. One of the ways of using resources optimally is utilizing transferred water in distribution systems properly and preventing its loss. Unaccounted for water (UFW) is an indicator of water loss in most cities. A big part of UFW is due to leakage of pipeline in distribution systems. Researchers have found direct relation between leakage and pressure in distribution systems. Earlier works have shown a series of laboratory...
Evaluation of Urban Water Distribution Network Resilience and Development of New Software based on Resilience Criteria Using Concurrent Discrete Event and Hydraulic Simulation(Case Study: Eslamshahr Water Distribution Network)
, M.Sc. Thesis Sharif University of Technology ; Mortaheb, Mohammad Mehdi (Supervisor) ; Hassani, Nemat (Co-Advisor)
Abstract
This dissertation proposes a new platform and a new software for evaluation of urban Water Distribution Network (WDN) resilience. Resilience is considerd as the ability of an infrastructure to come back to steady state after being affected by any environmental or man-made disturbance. WDN, as an essential infrastructure, has major role on resilience and sustainability of cities and communities. Today, uninterrupted performance of WDN is a basic need of people who live in cities. This uninterrupted performance becomes bolder in face of man-made or natural disasters like earthquake. The uninterrupted performance of a system is dependent on the system’s resilience. Majority of researchers...
Modeling Reaction and Distribution of Water in Nanopores of the Cathode Catalyst Layer of PEM Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; baghalha, morteza (Supervisor)
Abstract
In the proton exchange membrane fuel cells (PEM, the produced water would be divided into two phases of vapor and liquid. distribution of both liquid and vapor phases in different cell layers affects the performance, the efficiency and the life of a fuel cell significantly. Moreover, Nano pores of the cathode catalyst layer are involved with some phenomena such as electrochemical reaction kinetics, heat and mass transfer and interface phase change. One of the most important problems in the performance of fuel cells is distribution of liquid water in the porous areas. Water flooding in fuel cells causes to delay in oxygen transport to active sites in the catalyst layer because the pores of...
Chemical and Petroleum Engineering Department
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor) ; Baghalha, Morteza (Supervisor)
Abstract
Fuel Cell with Polymer membrane uses a reaction with Hydrogen and Oxygen as reactants to produce electricity. As the product of this reaction is water, this fuel cell produce clean energy. But if the produced water accumulates it can cause problems for fuel cell which can lead to complete failed of fuel cell. On the other hand water shortage in PEM fuel cell also can cause problems. So we need to have continues water management inside of PEM fuel cell. For this sake having knowledge about water inside of PEM fuel cell and specially the Gas Diffusion Layer which is the layer with responsibly to help the fuel cell to manage the water, is necessary. One of the ways for gaining that knowledge...
A resilience-based practical platform and novel index for rapid evaluation of urban water distribution network using hybrid simulation
, Article Sustainable Cities and Society ; Volume 82 , 2022 ; 22106707 (ISSN) ; Mortaheb, M. M ; Hassani, N ; Taghizadeh yazdi, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
This article proposes a novel index along with a user-friendly platform for resilience evaluation of the urban water distribution networks (WDN). WDN is of great importance in preserving the safety and sustainability of communities and cities. Resilience of a given system results in its sustainability. In recent years, many studies have focused on resilient urban WDN. However, these studies did not provide a comprehensive evaluation index and platform that could simultaneously consider hydraulic analysis, resilience parameters, and significant uncertainties. In this study, a novel resilience index was defined, and a user-friendly and practical platform (REWAT) was developed to calculate the...
Energy, economic and environmental (3E) analysis of a micro gas turbine employed for on-site combined heat and power production
, Article Energy and Buildings ; Volume 42, Issue 2 , 2010 , Pages 259-264 ; 03787788 (ISSN) ; Mozafari, A ; Sharif University of Technology
2010
Abstract
This paper studies the optimization of micro turbine application to meet the electrical, heating and cooling loads of a building by energy, economics and environmental analysis. In this study following three cases are considered: 1: A simple micro gas turbine to meet the electrical power of the building. 2: A simple micro gas turbine to meet the electrical power of the building as well as the power required by heat pump and mechanical refrigerator needed for heating, cooling and domestic hot water (DHW) systems. 3: A CHP micro gas turbine to meet the electrical power of the building as well as part of the power required by heat pump and mechanical refrigerator needed for heating, cooling and...
Multi-criteria decision making for integrated urban water management
, Article Water Resources Management ; Volume 22, Issue 8 , 2008 , Pages 1017-1029 ; 09204741 (ISSN) ; Abrishamchi, A ; Ardakanian, R ; Sharif University of Technology
2008
Abstract
The city of Zahedan, in South-eastern Iran, has high population growth, limited local freshwater resources and inadequate water distribution system resulting in water supply failures in recent years. This paper will investigate integration of several demand management measures such as leakage detection on water distribution network, water metering and low volume water fixtures as well as the conjunctive use of surface and groundwater resources of this city. For integration of water management criteria, compromise programming will be used as a multi-objective decision making method. The criteria include minimizing the cost, maximizing water supply and minimizing the social hazards due to the...