Shoaib Khanmohammadi | University of Guilan (original) (raw)
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Papers by Shoaib Khanmohammadi
Energy Conversion and Management, 2014
This paper presents a thermodynamic and exergoeconomic analysis of a recently-retrofitted Passivh... more This paper presents a thermodynamic and exergoeconomic analysis of a recently-retrofitted Passivhaus non-domestic building. The selected case study, a Community Centre located in London, underwent a deep-energy retrofit in 2011, becoming the first 'non-domestic Passivhaus' retrofit in the country. As the building was retrofitted per Passivhaus standards, which is based solely on First Law analysis, a thermodynamic investigation can provide a novel means by which to assess its exergy efficiency and costeffectiveness. As such, the aim of this paper is to conduct a comprehensive exergy and exergoeconomic analysis, presenting novel performance indicators for the pre-retrofit and post-retrofit Passivhaus building. First law outputs show that the improvement presents high levels of energy savings (75.6%), reductions in carbon emissions (64.5%), and occupant thermal comfort improvement (28.8%). Second law outputs present a reduction in primary exergy input reduction of 56.4% and exergy destructions of 60.4%, leading to improve building exergy efficiency from 9.8% to 18.0%. Nevertheless, exergoeconomically the building did not perform as expected due to high capital cost and exergy destructions cost rates. These results give an insight into the thermodynamic impact of the Passivhaus approach, providing a critical assessment of the strengths and limitations of the standard under both thermodynamic laws.
Solar Energy, 2020
Abstract The primary goal of the current study is thermodynamic and environmental modeling and mu... more Abstract The primary goal of the current study is thermodynamic and environmental modeling and multi-objective optimization of a new hybrid energy system. The suggested ocean-based energy conversion system consists of an organic Rankine cycle (ORC), a solar flat plate collector, a proton exchange membrane (PEM) electrolyzer boosted with thermoelectric generator (TEG) module. Exergy and exergo-environmental as two powerful tools are employed to the precise assessment of the suggested system. To achieve the best performance of the integrated system, multi-criteria optimization with different objective functions is carried out. As the results of the parametric analysis indicate, defined objective goals have an appropriate conflict with changing decision variables, which is necessary in multi-criteria optimization. Four decision variables namely solar flat plate collector area ( A p ), solar radiation intensity (I), collector temperature ( T col ), and condenser temperature ( T cond ) are chosen as decision variables. In all optimization scenarios, the net output power is common, which is based on the selected optimum points value changing between 201.02 kW and 268.17 kW. Additionally, in various optimization scenarios, the area of solar flat plate collectors tends to get a higher value in the allowable domain. The provided information in multi-objective optimization can provide good insight to engineers and system designers to select the best system configuration.
Mediterranean Green Buildings & Renewable Energy, 2016
International Journal of Chemical Engineering, 2016
The use of biomass due to the reduction in greenhouse gas emissions and environmental impacts has... more The use of biomass due to the reduction in greenhouse gas emissions and environmental impacts has attracted many researchers’ attention in the recent years. Access to an energy conversion system which is able to have the optimum performance for applying valuable low heating value fuels has been considered by many practitioners and scholars. This paper focuses on the accurate modeling of biomass gasification process and the optimal design of a multigeneration system (heating, cooling, electrical power, and hydrogen as energy carrier) to take the advantage of this clean energy. In the process of gasification modeling, a thermodynamic equilibrium model based on Gibbs energy minimization is used. Also, in the present study, a detailed parametric analysis of multigeneration system for undersigning the behavior of objective functions with changing design parameters and obtaining the optimal design parameters of the system is done as well. The results show that with exergy efficiency as an...
Sustainable Aviation, 2016
International Journal of Energy Research, 2008
Abstract Combined cycle power plants (CCPPs) have an important role in power generation. The ob... more Abstract Combined cycle power plants (CCPPs) have an important role in power generation.
The objective of this paper is to evaluate irreversibility of each part of Neka CCPP using the
exergy analysis. The results show that the combustion chamber, gas turbine, duct burner
and heat recovery steam generator (HRSG) are the main sources of irreversibility
representing more than 83% of the overall exergy losses. The results show that the greatest
exergy loss in the gas turbine occurs in the combustion chamber due to its high ...
This study deals with thermodynamic and economic analysis of a combined gas turbine and Organic... more This study deals with thermodynamic and economic analysis of a combined gas
turbine and Organic Rankine Cycle integrated with a biomass gasifier. A modified model is
used to increase the precision of the gasifier thermodynamic model. Seven decision
variables, namely, biomass gasification temperature (T gasif), combustion temperature (T
comb), gas turbine inlet temperature (T 3), gas turbine isentropic efficiency (η GT),
compressor isentropic efficiency (η comp), compressor pressure ration (rp) and maximum ...
The application of the exergy and exergoeconomic analysis for energy conversion systems is grow... more The application of the exergy and exergoeconomic analysis for energy conversion
systems is growing steadily. This analysis is particularly useful for energy conversion
systems such as the combined-cycle power plant (CCPP). This paper deals with exergy and
exergoeconomic analysis of a combined-cycle power plant with supplementary firing. A
process simulation program, IPSE Pro, is used to model the combined-cycle power plant.
Exergy and exergoeconomic analysis is carried out by developing a Matlab code. Three ...
Springer, 2015
This chapter deals with thermodynamic modeling, parametric analysis, and optimization of an int... more This chapter deals with thermodynamic modeling, parametric analysis, and
optimization of an integrated system to recover energy from pressure reduction station in city
gate station (CGS). This chapter aims to fully cover the thermodynamic modeling of an
integrated system consisting of a turbo expander, an organic Rankine cycle (ORC) and a
proton exchange membrane (PEM) electrolyzer to produce and store hydrogen. The
pressure of natural gas in transmission pipeline in Iran gas system is high which ...
The objective of this paper is to perform the exergy and exergo-economic analysis of Isfahan stea... more The objective of this paper is to perform the exergy and exergo-economic analysis of Isfahan steam power plant. A simulation program is used for modelling the Isfahan steam power plant in Iran. The exergy balance is used to estimate the exergy destruction in each component of the plant. Moreover, the cost balance equations are solved to determine the cost of exergy destruction in each part of the Isfahan STPP. The highest exergy destruction has mainly occurred in boiler and preheater1&condenser by almost 360.65 MW and 38.81 MW, respectively. In addition, the cost destruction for boiler is about 15090.8 US$/h and for preheater1&condenser is 6056.57 US$/h. Furthermore, the effect of key parameters such as the main steam temperature, reheated steam temperature, condenser pressure and number of the feed water heaters on the cycle performance as well as the final cost of electricity is determined. In particular, by decreasing the condenser, pressure from 0.7 to 0.05 bar the final cost of...
The supplementary firing is one of the techniques which are used to increase the output power of ... more The supplementary firing is one of the techniques which are used to increase the output power of the combined cycle power plants (CCPP). The low construction cost per generated power encourages designers to consider it in the new CCPP. In this paper exergy analyses of HRSG with and without supplementary firing are presented. They are based on the performance test data at different operating conditions. The objective of these analyses is to present the effects of supplementary firing on gross power output, combined cycle efficiency and the exergy loss in Heat Recovery Steam Generator (HRSG) devices at different ambient temperatures. The results show that the most effective components for the exergy losses are stack, LP-EV and LP-SH at different ambient temperature.
The effect of the supplementary firing on the exergy loss has been studied as well. The results reveal that although the supplementary firing increases the gross output power of the combined cycle power plant, however it increases the total exergy loss of HRSG and consequently decreases the total exergy and thermal efficiency.
Modares Mechanical Engineering Journal, 2015
The first law of thermodynamics is a useful tool for thermodynamics processes analysis. The exerg... more The first law of thermodynamics is a useful tool for thermodynamics processes analysis. The exergy analysis of a conventional steam power plant was done. This analysis is based on first and second law of thermodynamics. In the present paper, a conventional steam power plant was investigated using a thermoeconomic analysis. Having done this analysis the inefficient components of a steam power plant cycle was identified. In this analysis, it was assumed that the cycle components are adiabatic and the potential and kinetic terms of exergy were negligible. The exergy analysis combined with the economical aspects. These aspects include capital investment cost, fuel cost and operating and maintenance cost for evaluation of final cost of product. According to this calculation exergy destruction cost of each component in the cycle and their role were evaluated. Based on these results the effect of the component efficiency on the final cost of the product and performance revealed. Effect of main steam temperature, reheated temperature, condenser pressure and number of the feed water heaters on cycle performance and final electrical power cost were also determined.
This paper deals with thermodynamic modeling, parametric analysis and optimization of a novel int... more This paper deals with thermodynamic modeling, parametric analysis and optimization of a novel integrated system to recover energy from pressure reduction in city gate station (CGS). This research cover thermodynamic modeling of a hybrid system includes a turbo expander, an organic Rankine cycle (ORC) and a Proton Exchange Membrane (PEM) electrolyzer to produce electricity and hydrogen. The pressure of natural gas in transmission pipeline in Iran gas system is high about 7 MPa. Since, near the cities pipeline pressure should be reducing to 1.7 MPa, there is a great potential to recover energy to produce electricity and other energy products. In the proposed integrated system in this paper, a comprehensive parametric analysis include the effect of main parameters such as natural gas preheat temperature, the natural gas pressure inlet to turbo expander, the heater mass fuel flue rate and high temperature of ORC on the system performance is investigated. The results show that although, the natural gas inlet pressure has a trivial effect on exergy efficiency of ORC, PEM electrolyzer and turbo expander, it has an important effect on turbo expander power output and hydrogen production rate. Besides, results indicate that increase preheat temperature of natural gas from 130 ℃ to 165 ℃ has the favorable effect on the turbo expander power output and exergy destruction rate of ORC components. Also, it can be concluded that increases preheat temperature leads to decrease hydrogen production from 15.9 kg/day to 14.8kg/day due to decrease ORC output work. In order to find the optimum value of design parameters an optimization method is applied. The genetic algorithm optimization results show there are acceptable values for five design parameters which guarantee the optimum performance of the novel proposed integrated system.
Energy Conversion and Management, 2014
This paper presents a thermodynamic and exergoeconomic analysis of a recently-retrofitted Passivh... more This paper presents a thermodynamic and exergoeconomic analysis of a recently-retrofitted Passivhaus non-domestic building. The selected case study, a Community Centre located in London, underwent a deep-energy retrofit in 2011, becoming the first 'non-domestic Passivhaus' retrofit in the country. As the building was retrofitted per Passivhaus standards, which is based solely on First Law analysis, a thermodynamic investigation can provide a novel means by which to assess its exergy efficiency and costeffectiveness. As such, the aim of this paper is to conduct a comprehensive exergy and exergoeconomic analysis, presenting novel performance indicators for the pre-retrofit and post-retrofit Passivhaus building. First law outputs show that the improvement presents high levels of energy savings (75.6%), reductions in carbon emissions (64.5%), and occupant thermal comfort improvement (28.8%). Second law outputs present a reduction in primary exergy input reduction of 56.4% and exergy destructions of 60.4%, leading to improve building exergy efficiency from 9.8% to 18.0%. Nevertheless, exergoeconomically the building did not perform as expected due to high capital cost and exergy destructions cost rates. These results give an insight into the thermodynamic impact of the Passivhaus approach, providing a critical assessment of the strengths and limitations of the standard under both thermodynamic laws.
Solar Energy, 2020
Abstract The primary goal of the current study is thermodynamic and environmental modeling and mu... more Abstract The primary goal of the current study is thermodynamic and environmental modeling and multi-objective optimization of a new hybrid energy system. The suggested ocean-based energy conversion system consists of an organic Rankine cycle (ORC), a solar flat plate collector, a proton exchange membrane (PEM) electrolyzer boosted with thermoelectric generator (TEG) module. Exergy and exergo-environmental as two powerful tools are employed to the precise assessment of the suggested system. To achieve the best performance of the integrated system, multi-criteria optimization with different objective functions is carried out. As the results of the parametric analysis indicate, defined objective goals have an appropriate conflict with changing decision variables, which is necessary in multi-criteria optimization. Four decision variables namely solar flat plate collector area ( A p ), solar radiation intensity (I), collector temperature ( T col ), and condenser temperature ( T cond ) are chosen as decision variables. In all optimization scenarios, the net output power is common, which is based on the selected optimum points value changing between 201.02 kW and 268.17 kW. Additionally, in various optimization scenarios, the area of solar flat plate collectors tends to get a higher value in the allowable domain. The provided information in multi-objective optimization can provide good insight to engineers and system designers to select the best system configuration.
Mediterranean Green Buildings & Renewable Energy, 2016
International Journal of Chemical Engineering, 2016
The use of biomass due to the reduction in greenhouse gas emissions and environmental impacts has... more The use of biomass due to the reduction in greenhouse gas emissions and environmental impacts has attracted many researchers’ attention in the recent years. Access to an energy conversion system which is able to have the optimum performance for applying valuable low heating value fuels has been considered by many practitioners and scholars. This paper focuses on the accurate modeling of biomass gasification process and the optimal design of a multigeneration system (heating, cooling, electrical power, and hydrogen as energy carrier) to take the advantage of this clean energy. In the process of gasification modeling, a thermodynamic equilibrium model based on Gibbs energy minimization is used. Also, in the present study, a detailed parametric analysis of multigeneration system for undersigning the behavior of objective functions with changing design parameters and obtaining the optimal design parameters of the system is done as well. The results show that with exergy efficiency as an...
Sustainable Aviation, 2016
International Journal of Energy Research, 2008
Abstract Combined cycle power plants (CCPPs) have an important role in power generation. The ob... more Abstract Combined cycle power plants (CCPPs) have an important role in power generation.
The objective of this paper is to evaluate irreversibility of each part of Neka CCPP using the
exergy analysis. The results show that the combustion chamber, gas turbine, duct burner
and heat recovery steam generator (HRSG) are the main sources of irreversibility
representing more than 83% of the overall exergy losses. The results show that the greatest
exergy loss in the gas turbine occurs in the combustion chamber due to its high ...
This study deals with thermodynamic and economic analysis of a combined gas turbine and Organic... more This study deals with thermodynamic and economic analysis of a combined gas
turbine and Organic Rankine Cycle integrated with a biomass gasifier. A modified model is
used to increase the precision of the gasifier thermodynamic model. Seven decision
variables, namely, biomass gasification temperature (T gasif), combustion temperature (T
comb), gas turbine inlet temperature (T 3), gas turbine isentropic efficiency (η GT),
compressor isentropic efficiency (η comp), compressor pressure ration (rp) and maximum ...
The application of the exergy and exergoeconomic analysis for energy conversion systems is grow... more The application of the exergy and exergoeconomic analysis for energy conversion
systems is growing steadily. This analysis is particularly useful for energy conversion
systems such as the combined-cycle power plant (CCPP). This paper deals with exergy and
exergoeconomic analysis of a combined-cycle power plant with supplementary firing. A
process simulation program, IPSE Pro, is used to model the combined-cycle power plant.
Exergy and exergoeconomic analysis is carried out by developing a Matlab code. Three ...
Springer, 2015
This chapter deals with thermodynamic modeling, parametric analysis, and optimization of an int... more This chapter deals with thermodynamic modeling, parametric analysis, and
optimization of an integrated system to recover energy from pressure reduction station in city
gate station (CGS). This chapter aims to fully cover the thermodynamic modeling of an
integrated system consisting of a turbo expander, an organic Rankine cycle (ORC) and a
proton exchange membrane (PEM) electrolyzer to produce and store hydrogen. The
pressure of natural gas in transmission pipeline in Iran gas system is high which ...
The objective of this paper is to perform the exergy and exergo-economic analysis of Isfahan stea... more The objective of this paper is to perform the exergy and exergo-economic analysis of Isfahan steam power plant. A simulation program is used for modelling the Isfahan steam power plant in Iran. The exergy balance is used to estimate the exergy destruction in each component of the plant. Moreover, the cost balance equations are solved to determine the cost of exergy destruction in each part of the Isfahan STPP. The highest exergy destruction has mainly occurred in boiler and preheater1&condenser by almost 360.65 MW and 38.81 MW, respectively. In addition, the cost destruction for boiler is about 15090.8 US$/h and for preheater1&condenser is 6056.57 US$/h. Furthermore, the effect of key parameters such as the main steam temperature, reheated steam temperature, condenser pressure and number of the feed water heaters on the cycle performance as well as the final cost of electricity is determined. In particular, by decreasing the condenser, pressure from 0.7 to 0.05 bar the final cost of...
The supplementary firing is one of the techniques which are used to increase the output power of ... more The supplementary firing is one of the techniques which are used to increase the output power of the combined cycle power plants (CCPP). The low construction cost per generated power encourages designers to consider it in the new CCPP. In this paper exergy analyses of HRSG with and without supplementary firing are presented. They are based on the performance test data at different operating conditions. The objective of these analyses is to present the effects of supplementary firing on gross power output, combined cycle efficiency and the exergy loss in Heat Recovery Steam Generator (HRSG) devices at different ambient temperatures. The results show that the most effective components for the exergy losses are stack, LP-EV and LP-SH at different ambient temperature.
The effect of the supplementary firing on the exergy loss has been studied as well. The results reveal that although the supplementary firing increases the gross output power of the combined cycle power plant, however it increases the total exergy loss of HRSG and consequently decreases the total exergy and thermal efficiency.
Modares Mechanical Engineering Journal, 2015
The first law of thermodynamics is a useful tool for thermodynamics processes analysis. The exerg... more The first law of thermodynamics is a useful tool for thermodynamics processes analysis. The exergy analysis of a conventional steam power plant was done. This analysis is based on first and second law of thermodynamics. In the present paper, a conventional steam power plant was investigated using a thermoeconomic analysis. Having done this analysis the inefficient components of a steam power plant cycle was identified. In this analysis, it was assumed that the cycle components are adiabatic and the potential and kinetic terms of exergy were negligible. The exergy analysis combined with the economical aspects. These aspects include capital investment cost, fuel cost and operating and maintenance cost for evaluation of final cost of product. According to this calculation exergy destruction cost of each component in the cycle and their role were evaluated. Based on these results the effect of the component efficiency on the final cost of the product and performance revealed. Effect of main steam temperature, reheated temperature, condenser pressure and number of the feed water heaters on cycle performance and final electrical power cost were also determined.
This paper deals with thermodynamic modeling, parametric analysis and optimization of a novel int... more This paper deals with thermodynamic modeling, parametric analysis and optimization of a novel integrated system to recover energy from pressure reduction in city gate station (CGS). This research cover thermodynamic modeling of a hybrid system includes a turbo expander, an organic Rankine cycle (ORC) and a Proton Exchange Membrane (PEM) electrolyzer to produce electricity and hydrogen. The pressure of natural gas in transmission pipeline in Iran gas system is high about 7 MPa. Since, near the cities pipeline pressure should be reducing to 1.7 MPa, there is a great potential to recover energy to produce electricity and other energy products. In the proposed integrated system in this paper, a comprehensive parametric analysis include the effect of main parameters such as natural gas preheat temperature, the natural gas pressure inlet to turbo expander, the heater mass fuel flue rate and high temperature of ORC on the system performance is investigated. The results show that although, the natural gas inlet pressure has a trivial effect on exergy efficiency of ORC, PEM electrolyzer and turbo expander, it has an important effect on turbo expander power output and hydrogen production rate. Besides, results indicate that increase preheat temperature of natural gas from 130 ℃ to 165 ℃ has the favorable effect on the turbo expander power output and exergy destruction rate of ORC components. Also, it can be concluded that increases preheat temperature leads to decrease hydrogen production from 15.9 kg/day to 14.8kg/day due to decrease ORC output work. In order to find the optimum value of design parameters an optimization method is applied. The genetic algorithm optimization results show there are acceptable values for five design parameters which guarantee the optimum performance of the novel proposed integrated system.