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Yasin Ust - One of the best experts on this subject based on the ideXlab platform.

  • Thermodynamic optimization of an irreversible regenerative closed Brayton cycle based on thermoeconomic Performance Criterion
    Applied Mathematical Modelling, 2014
    Co-Authors: Yalcin Durmusoglu, Yasin Ust
    Abstract:

    Abstract An irreversible regenerative closed Brayton cycle has been optimized using a thermoeconomic objective Criterion which is defined as the ratio of net power output to the total cost rate. The total cost rate includes fuel, investment, environmental and operation & maintenance cost rates. In the considered model pressure drops, heat leakages, irreversibilities due to finite-rate heat transfer and internal dissipations have been included. The effects of design parameters, such as isentropic temperature ratio of compressor and turbine, regenerator effectiveness, pressure loss parameter of the cycle, on the general and optimal thermoeconomic Performances have been investigated in detail. The results of the study will be helpful for the Performance analysis and optimization of practical Brayton heat engine systems.

  • Performance analysis and optimization of irreversible air refrigeration cycles based on ecological coefficient of Performance Criterion
    Applied Thermal Engineering, 2009
    Co-Authors: Yasin Ust
    Abstract:

    In this paper, a Performance optimization based on ecological coefficient of Performance (ECOP) Criterion has been carried out for an irreversible air refrigeration cycles. The considered model includes irreversibilities due to finite-rate heat transfer, heat leakage and internal dissipations. The ECOP objective function is defined as the ratio of cooling load to the loss rate of availability (or entropy generation rate). The maximum of the ecological Performance Criterion and the corresponding optimal conditions have been derived analytically. The effects of irreversibility parameters on the general and optimal Performances discussed detailed. The obtained results may provide a general theoretical tool for the ecological design of air refrigerators.

  • optimization of a dual cycle cogeneration system based on a new exergetic Performance Criterion
    Applied Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Ali Kodal
    Abstract:

    An ecological Performance analysis for an irreversible dual-cycle cogeneration system has been performed. The objective function is called as the exergetic-Performance coefficient (EPC) and defined as the ratio of total exergy output to the loss rate of availability. The general and optimal Performances of the irreversible dual-cycle cogeneration system, having a finite-rate of heat transfer, heat leak and internal irreversibilities based on the EPC objective function have been investigated. Comparisons with respect to the optimal total-exergy output are also provided in order to establish the utility of the new exergetic-Performance coefficient. The analyzed results of the dual-cycle cogeneration system considered, working at maximum EPC conditions, have a significant advantage in terms of entropy-generation rate and can be used for the selection of optimal design parameters.

  • optimization of a regenerative gas turbine cogeneration system based on a new exergetic Performance Criterion exergetic Performance coefficient
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Tamer Yilmaz
    Abstract:

    AbstractA Performance analysis and an optimization based on a new exergetic Performance Criterion named exergetic Performance coefficient (EPC) have been carried out for an irreversible regenerative gas-turbine cogeneration system. The EPC objective function defined as the total exergy output per unit loss rate of availability is taken as the optimization Criterion. The design parameters and Performances under optimal conditions have been investigated and the results obtained are compared with those obtained using the alternative criteria given in the literature. It is shown that for the regenerative gas-turbine cogeneration system, a design based on the maximum EPC conditions is more advantageous from the viewpoint of entropy generation rate, exergy efficiency, and investment cost.

David Banjerdpongchai - One of the best experts on this subject based on the ideXlab platform.

  • design of state feedback control for polynomial systems with quadratic Performance Criterion and control input constraints
    Systems & Control Letters, 2018
    Co-Authors: Tanagorn Jennawasin, David Banjerdpongchai
    Abstract:

    Abstract This paper presents a novel convex optimization approach to design state-feedback control for polynomial systems. Design criteria are comprised of a quadratic cost function and bounded magnitudes of control inputs. Specifically, we formulate a control synthesis of closed-loop systems operated in a given bounded domain characterized by a semi-algebraic set. We consider an extended class of rational Lyapunov functions and derive an upper bound of the cost function, together with a state-feedback control law. By exploiting bounds on the control input magnitudes, the controller design condition can be cast as a parameter-dependent linear matrix inequality (PDLMI), which is convex optimization and can be efficiently solved by sum-of-squares (SOS) technique. In addition, we derive a sufficient condition to compute a lower bound of the cost function. When choosing polynomial structure of the solution candidate, the lower bound can also be written as PDLMI. Numerical examples are provided to illustrate the effectiveness of the proposed design.

  • an lmi approach for robust iterative learning control with quadratic Performance Criterion
    Journal of Process Control, 2009
    Co-Authors: Dinh Hoa Nguyen, David Banjerdpongchai
    Abstract:

    Abstract This paper presents the design of iterative learning control based on quadratic Performance Criterion (Q-ILC) for linear systems subject to additive uncertainty. The robust Q-ILC design can be cast as a min–max problem. We propose a novel approach which employs an upper bound of the worst-case Performance, then formulates a non-convex quadratic minimization problem to get the update of iterative control inputs. Applying Lagrange duality, the Lagrange dual function of the non-convex quadratic problem is equivalent to a convex optimization over linear matrix inequalities (LMIs). An LMI algorithm with convergence properties is then given for the robust Q-ILC design. Finally, we provide a numerical example to illustrate the effectiveness of the proposed method.

  • an lmi approach for robust iterative learning control with quadratic Performance Criterion
    International Conference on Control Automation Robotics and Vision, 2008
    Co-Authors: Dinh Hoa Nguyen, David Banjerdpongchai
    Abstract:

    This paper presents the design of iterative learning control based on Quadratic Performance Criterion (Q-ILC) for linear systems subject to additive uncertainty. Robust Q-ILC design can be cast as a min-max problem. We propose a novel approach which employs an upper bound of the worst-case error, then formulates a nonconvex quadratic minimization problem to get the update of iterative control inputs. Applying Langrange duality, the Lagrange dual function of the nonconvex quadratic problem is equivalent to a convex optimization over linear matrix inequalities (LMIs). An LMI algorithm with convergence properties is then given for the robust Q-ILC. Finally, we provide a numerical example to illustrate the effectiveness of the proposed method.

Bahri şahin - One of the best experts on this subject based on the ideXlab platform.

  • Performance optimization of an air standard irreversible dual atkinson cycle engine based on the ecological coefficient of Performance Criterion
    The Scientific World Journal, 2014
    Co-Authors: Guven Gonca, Bahri şahin
    Abstract:

    This paper presents an ecological Performance analysis and optimization for an air-standard irreversible Dual-Atkinson cycle (DAC) based on the ecological coefficient of Performance (ECOP) Criterion which includes internal irreversibilities, heat leak, and finite-rate of heat transfer. A comprehensive numerical analysis has been realized so as to investigate the global and optimal Performances of the cycle. The results obtained based on the ECOP Criterion are compared with a different ecological function which is named as the ecologic objective-function and with the maximum power output conditions. The results have been attained introducing the compression ratio, cut-off ratio, pressure ratio, Atkinson cycle ratio, source temperature ratio, and internal irreversibility parameter. The change of cycle Performance with respect to these parameters is investigated and graphically presented.

  • optimization of a dual cycle cogeneration system based on a new exergetic Performance Criterion
    Applied Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Ali Kodal
    Abstract:

    An ecological Performance analysis for an irreversible dual-cycle cogeneration system has been performed. The objective function is called as the exergetic-Performance coefficient (EPC) and defined as the ratio of total exergy output to the loss rate of availability. The general and optimal Performances of the irreversible dual-cycle cogeneration system, having a finite-rate of heat transfer, heat leak and internal irreversibilities based on the EPC objective function have been investigated. Comparisons with respect to the optimal total-exergy output are also provided in order to establish the utility of the new exergetic-Performance coefficient. The analyzed results of the dual-cycle cogeneration system considered, working at maximum EPC conditions, have a significant advantage in terms of entropy-generation rate and can be used for the selection of optimal design parameters.

  • optimization of a regenerative gas turbine cogeneration system based on a new exergetic Performance Criterion exergetic Performance coefficient
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 2007
    Co-Authors: Bahri şahin, Tamer Yilmaz
    Abstract:

    AbstractA Performance analysis and an optimization based on a new exergetic Performance Criterion named exergetic Performance coefficient (EPC) have been carried out for an irreversible regenerative gas-turbine cogeneration system. The EPC objective function defined as the total exergy output per unit loss rate of availability is taken as the optimization Criterion. The design parameters and Performances under optimal conditions have been investigated and the results obtained are compared with those obtained using the alternative criteria given in the literature. It is shown that for the regenerative gas-turbine cogeneration system, a design based on the maximum EPC conditions is more advantageous from the viewpoint of entropy generation rate, exergy efficiency, and investment cost.

  • optimization of a regenerative gas turbine cogeneration system based on a new exergetic Performance Criterion exergetic Performance coefficient
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Tamer Yilmaz
    Abstract:

    AbstractA Performance analysis and an optimization based on a new exergetic Performance Criterion named exergetic Performance coefficient (EPC) have been carried out for an irreversible regenerative gas-turbine cogeneration system. The EPC objective function defined as the total exergy output per unit loss rate of availability is taken as the optimization Criterion. The design parameters and Performances under optimal conditions have been investigated and the results obtained are compared with those obtained using the alternative criteria given in the literature. It is shown that for the regenerative gas-turbine cogeneration system, a design based on the maximum EPC conditions is more advantageous from the viewpoint of entropy generation rate, exergy efficiency, and investment cost.

Ali Kodal - One of the best experts on this subject based on the ideXlab platform.

  • optimization of a dual cycle cogeneration system based on a new exergetic Performance Criterion
    Applied Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Ali Kodal
    Abstract:

    An ecological Performance analysis for an irreversible dual-cycle cogeneration system has been performed. The objective function is called as the exergetic-Performance coefficient (EPC) and defined as the ratio of total exergy output to the loss rate of availability. The general and optimal Performances of the irreversible dual-cycle cogeneration system, having a finite-rate of heat transfer, heat leak and internal irreversibilities based on the EPC objective function have been investigated. Comparisons with respect to the optimal total-exergy output are also provided in order to establish the utility of the new exergetic-Performance coefficient. The analyzed results of the dual-cycle cogeneration system considered, working at maximum EPC conditions, have a significant advantage in terms of entropy-generation rate and can be used for the selection of optimal design parameters.

  • Performance analysis of an irreversible brayton heat engine based on ecological coefficient of Performance Criterion
    International Journal of Thermal Sciences, 2006
    Co-Authors: Ali Kodal
    Abstract:

    A Performance optimization based on a new ecological Criterion called ecological coefficient of Performance (ECOP) has been presented for irreversible Brayton heat engine. The considered model includes irreversibilities due to finite rate heat transfer, heat leakage and internal dissipations. The ECOP objective function is defined as the ratio of power output to the loss rate of availability. The optimal Performance and design parameters at maximum ECOP conditions are obtained analytically. The effects of major parameters on the general and optimal ecological Performances have been investigated. The obtained results based on ECOP Criterion are compared with an alternative ecological objective function defined in the literature and the maximum power output conditions, in terms of entropy generation rate, thermal efficiency and power output.

Tamer Yilmaz - One of the best experts on this subject based on the ideXlab platform.

  • optimization of a regenerative gas turbine cogeneration system based on a new exergetic Performance Criterion exergetic Performance coefficient
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 2007
    Co-Authors: Bahri şahin, Tamer Yilmaz
    Abstract:

    AbstractA Performance analysis and an optimization based on a new exergetic Performance Criterion named exergetic Performance coefficient (EPC) have been carried out for an irreversible regenerative gas-turbine cogeneration system. The EPC objective function defined as the total exergy output per unit loss rate of availability is taken as the optimization Criterion. The design parameters and Performances under optimal conditions have been investigated and the results obtained are compared with those obtained using the alternative criteria given in the literature. It is shown that for the regenerative gas-turbine cogeneration system, a design based on the maximum EPC conditions is more advantageous from the viewpoint of entropy generation rate, exergy efficiency, and investment cost.

  • optimization of a regenerative gas turbine cogeneration system based on a new exergetic Performance Criterion exergetic Performance coefficient
    Proceedings of the Institution of Mechanical Engineers Part A: Journal of Power and Energy, 2007
    Co-Authors: Yasin Ust, Bahri şahin, Tamer Yilmaz
    Abstract:

    AbstractA Performance analysis and an optimization based on a new exergetic Performance Criterion named exergetic Performance coefficient (EPC) have been carried out for an irreversible regenerative gas-turbine cogeneration system. The EPC objective function defined as the total exergy output per unit loss rate of availability is taken as the optimization Criterion. The design parameters and Performances under optimal conditions have been investigated and the results obtained are compared with those obtained using the alternative criteria given in the literature. It is shown that for the regenerative gas-turbine cogeneration system, a design based on the maximum EPC conditions is more advantageous from the viewpoint of entropy generation rate, exergy efficiency, and investment cost.

  • a new Performance Criterion for heat engines efficient power
    Journal of The Energy Institute, 2006
    Co-Authors: Tamer Yilmaz
    Abstract:

    AbstractMany Performance analyses have been carried out based on two comparative criteria namely maximum power (mp) and maximum power density (mpd). Researchers involved in power maximization studies have utilized the thermal efficiency at mp (Curzon–Ahlborn efficiency) as an efficiency standard for practical heat engines. On the other hand, maximum power density studies showed that the efficiency at mpd is always greater than that at the mp, while the power output from heat engines reduces. In this study, a new Performance analysis is applied to a reversible Carnot cycle based on a new Criterion which is proposed for all kind of heat engines. The proposed Criterion, called efficient power, is defined as the multiplication of power by efficiency. This Criterion considers not only the power output, but also the cycle efficiency. Maximizing the efficient power gives a compromise between power and efficiency. The results showed that the design parameters at maximum efficient power (mep) conditions lead to mo...