Search for: absorption-chiller
Integration of an absorption chiller in a total CHP site for utilizing its cooling production potential based on R-curve concept, Article International Journal of Refrigeration ; Volume 35, Issue 5 , 2012 , Pages 1384-1392 ; 01407007 (ISSN) ; Karimkashi, S ; Saidi, M. H ; Sharif University of Technology
Total site integration offers energy conservation opportunities across different individual processes. It also helps for design as well as optimization of the central utility system. It gives massive energy-saving opportunities. The large industrial CHP sites generate heat and power simultaneously. These sites have different steam levels at different pressures which are used for power generation via steam turbines and also directly for satisfying process heat demand. There are many sites requiring cooling demand in hot seasons. In this article, integration of a LiBr/water absorption chiller in a CHP site has been investigated until its cooling demand is satisfied. Low pressure steam at 3 bar...
M.Sc. Thesis Sharif University of Technology ; Farhadi, Fathollah
Compressor stations with gas turbine drive have become common in transport of natural gas. However, the thermal efficiency of the gas turbines used in these stations is low. One reason for this is that 70% of the heat of combustion of the fuel gas used by the gas turbine is lost with its exhaust gases. Hence, heat recovery from gas turbine exhaust gas would increase the cycle efficiency by decreasing the fuel gas consumed. On the other hand, gas turbine efficiency highly depends on the climatic conditions of operation. Among several well known methods of performance improvement, the use of an absorption chiller for inlet air cooling has been studied from both process and economic points of...
M.Sc. Thesis Sharif University of Technology ; Sadrhosseini, Hani ; Zabihollah, Abolghasem
Nowadays, gas turbines are from the most widely used devices in terms of power generation. According to their vital role in suppling electrical power required for daily life and their widespread application in power plants, tremendous efforts have been made to improve the efficiency of gas turbine working cycle. One of the most applicable methods to optimize a gas turbine is to cool the compressor inlet air. Applying an absorption chiller is a wisely technique especially when it comes to hot and humid weather condition. In this thesis, effects of applying an absorption chiller with specified technical facts on the performance of gas turbines, which are now functional in Kish Island power...
M.Sc. Thesis Sharif University of Technology ; Behshad Shafiee, Mohammad
Reducing fossil fuels and increasing urban air pollution, has made the automotive industry to reduce the fuel consumption of their engines by various approaches. Removing the compressor of air conditioning system by replacing the absorption chiller instead of inverse rankin cycle is a shortcut to reduce the fuel consumption which at the same time reduces costs of using air conditioning system for occupants. Design of a 3 kW lithium bromide-water absorbent chiller has verified based on environmental conditions and car space limitations and using the combustion products as the heat source of system. K4M engine of L90 sedan Car as an internal combustion engine sample’s exhaust manifold has been...
M.Sc. Thesis Sharif University of Technology ; Farhadi, Fatollah
Solar radiation is a clean and renewable energy which is essential for all natural processes of the planet earth. The benefits of solar ventilation are more than conventional cooling systems. In this research, simulation and modification of solar absorption chiller (LiBr) was investigated. TRNSYS simulator software and Esfahan climate data were used. First of all, collector slope, rate of solar cycle pump, size of heat storage tank and size of collector were modified. Then, operation cost of a 5 tones solar cooling system with flat plate collector and evacuated tube collector was compared with conventional 5 tones capacity cooling systems such as direct fired absorption chiller and vapor...
Velocity distributions in (r,θ) directions for laminar flow of a film around horizontal circular tube, Article 2006 2nd ASME Joint U.S.-European Fluids Engineering Summer Meeting, FEDSM 2006, Miami, FL, 17 July 2006 through 20 July 2006 ; Volume 2006 , 2006 ; 0791837831 (ISBN); 9780791837832 (ISBN) ; Saidi, M. H ; Sharif University of Technology
Velocity distributions in (r,θ) directions are evaluated by solving simultaneous simplified Navier-Stokes equations (NSE) and continuity equation (CE) in polar coordinate. The analysis is based on steady state laminar flow of thin falling liquid film on a horizontal circular tube, for cases in which traction on the film surface is considered negligible. It is a common geometry for part of engineering problems such as evaporator, condenser, absorber, generator of absorption chillers and other similar units in mechanical and chemical engineering. Knowledge of the velocity profiles is usually needed for: 1- solving governing energy and species equations 2- estimating the average and film...
Selection of prime mover to meet heating demand of a single effect absorption chiller based on laws of thermodynamics, Article SN Applied Sciences ; Volume 3, Issue 1 , 2021 ; 25233971 (ISSN) ; Saidi, M. H ; Najafi, M ; Aghanajafi, C ; Sharif University of Technology
Springer Nature 2021
In this study the first and the second laws of thermodynamics are evaluated for a single effect absorption chiller. Entropy generation and COP are selected as the objective functions and their variations are studied by varying the generator temperature for various condensing temperatures. For this purpose, the enthalpy and the entropy data of the super-heated steam, saturated steam and the saturated water are formulated in the mathematical equations. Also to provide the required steam of generator, prime mover in the form of internal combustion engine is applied and its partial load conditions are analyzed. A residential tower is considered as the case study for selecting the proper prime...
M.Sc. Thesis Sharif University of Technology ; Sattari, Sourena
In recent decades, due to economic, political and environmental issues, tend to use of the CHP systems (combined heating and power) have increased. CHP systems not only increase energy efficiency, but also decrease fuel consumption and emission levels of systems. The use of CHP technology in the industry has a long history, but the use of these systems in the commercial and residential sector, is considered, recently. As to the residential buildings, both electricity and thermal energy demands fluctuate seasonally and hourly, so it is necessary to take account of the plant’s annual operational strategies for the variations of load demands. In this paper, a nonlinear programming model is...
M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan ; Amidpour, Majid
In this investigation the thermodynamic, economic and environmental analysis of a 4rth generation system for simultaneous produce of heat, power, water and cooling of a residential building in Tehran-Iran has been done. Four different system have been used for power generation: 1-combined cycle of Direct Internal Reforming Solid Oxide Fuel Cell and Gas Turbine (IRSOFC-GT) 2-combined cycle of Gas Turbine and Steam Turbine (GT-ST) 3- cycle of Gas Turbine with Recuperator (GT-R) 4- cycle of Steam Turbine (ST). A double effect absorption chiller has utilized to provide the cooling load of the building, while a heat exchanger provides its thermal requirement. Also a MED-TVC system was used to...
Article Heat and Mass Transfer/Waerme- und Stoffuebertragung ; Volume 47, Issue 3 , November , 2011 , Pages 259-267 ; 09477411 (ISSN) ; Farhanieh, B ; Sharif University of Technology
Among major components of LiBr-H 2O absorption chillers is the absorber, which has a direct effect on the chillier size and whose characteristics have significant effects on the overall efficiency of absorption machines. In this article, heat and mass transfer process in absorption of refrigerant vapor into a lithium bromide solution of water-cooled incline plate absorber in the Reynolds number range of 5
Multi-criteria design optimization and thermodynamic analysis of a novel multi-generation energy system for hydrogen, cooling, heating, power, and freshwater, Article International Journal of Hydrogen Energy ; Volume 45, Issue 30 , 2020 , Pages 15047-15062 ; Rostami, M ; Farajollahi, A. H ; Sharif University of Technology
Elsevier Ltd 2020
The main focus of this paper is to present thermodynamic and economic analyses and multi-objective optimization of a novel geothermal-solar multigeneration system. The system aims to produce hydrogen, freshwater, electricity, cooling load, and hot water and designed based on geothermal and solar energy. After modeling and thermodynamic and economic analysis, exergy destruction rate, exergy efficiency and, cost rate were calculated for each component of the system. The results showed that the highest amount of exergy destruction was related to parabolic trough collectors (PTCs) and absorption chillers. To select the geothermal fluid of the organic Rankine cycle (ORC), several different fluids...
A comprehensive comparative investigation on solar heating and cooling technologies from a thermo-economic viewpoint—A dynamic simulation, Article Energy Science and Engineering ; December , 2020 ; Behnam, P ; Abbasi Kamazani, M ; Mohammadi, O ; Kavian, S ; Ahmadi, P ; Rosen, M. A ; Sharif University of Technology
John Wiley and Sons Ltd 2020
The yearly thermo-economic performance is dynamically investigated for three solar heating and cooling systems: solar heating and absorption cooling (SHAC), solar heating and ejector cooling (SHEC), and heating and solar vapor compression cooling (HSVC). First, the effects of important design parameters on the thermo-economic performance of the systems to supply the heating and cooling loads of the building are evaluated. The systems are parametrically analyzed with the weather conditions of Tehran, Iran. The results show that the life cycle costs (LCC) of the SHAC and HSVC systems are alike and much lower than those of the SHEC system. The HSVC system exhibits the best performance from...
Dynamic simulation of a trigeneration system using an absorption cooling system and building integrated photovoltaic thermal solar collectors, Article Journal of Building Engineering ; Volume 43 , November , 2021 ; 23527102 (ISSN) ; Fayaz, R ; Delfani, S ; Jafari Mosleh, H ; Karami, M ; Sharif University of Technology
Elsevier Ltd 2021
Solar systems are the most promising technologies to reduce building energy consumption. In recent years, one of the popular solar technologies is building integrated photovoltaic-thermal collectors, because of profitability and no need for separate architectural space. In this study, a new combination of glazed building integrated photovoltaic thermal solar collectors and an absorption cooling system, as a trigeneration system, to provide thermal and electrical energy demands of a case study residential building, is proposed. Dynamic simulation of the proposed system is performed using the TRNSYS-MATLAB co-simulator. Because there is no model for the glazed photovoltaic thermal solar...
Exergoeconomic optimization of a trigeneration system for heating, cooling and power production purpose based on TRR method and using evolutionary algorithm, Article Applied Thermal Engineering ; Volume 36, Issue 1 , 2012 , Pages 113-125 ; 13594311 (ISSN) ; Saidi, M. H ; Ahmadi, P ; Sharif University of Technology
In the present study, exergoeconomic optimization of a trigeneration system for cooling, heating and power purposes has been carried out. The system is made up of air compressor, combustion chamber, gas turbine, dual pressure heat recovery steam generator and absorption chiller in order to produce cooling, heating and power. The design parameters of this study are selected as: air compressor pressure ratio, gas turbine inlet temperature, pinch point temperatures in dual pressure heat recovery steam generator, pressure of steam that enters the generator of absorption chiller, process steam pressure and evaporator of the absorption chiller chilled water outlet temperature. The economic model...
Energy, exergy and thermoeconomic analysis of a combined cooling, heating and power (CCHP) system with gas turbine prime mover, Article International Journal of Energy Research ; Volume 35, Issue 8 , June , 2011 , Pages 697-709 ; 0363907X (ISSN) ; Amidpour, M ; Karimkashi, S ; Rezayan, O ; Sharif University of Technology
In this paper energy, exergy and thermoeconomic analysis of a combined cooling, heating and power (CCHP) system has been performed. Applying the first and second laws of thermodynamics and economic analysis, simultaneously, has made a powerful tool for the analysis of energy systems such as CCHP systems. The system integrates air compressor, combustion chamber, gas turbine, dual pressure heat recovery steam generator (HRSG) and absorption chiller to produce cooling, heating and power. In fact, the first and second laws of thermodynamics are combined with thermoeconomic approaches. Next, computational analysis is performed to investigate the effects of below items on the fuel consumption,...