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Juha Honkatukia - One of the best experts on this subject based on the ideXlab platform.

  • optimising the refrigeration cycle with a two stage centrifugal compressor and a flash Intercooler
    International Journal of Refrigeration-revue Internationale Du Froid, 2009
    Co-Authors: Pekka Röyttä, Teemu Turunensaaresti, Juha Honkatukia
    Abstract:

    The optimisation of a refrigeration process with a two-stage centrifugal compressor and flash Intercooler is presented in this paper. The two-stage centrifugal compressor stages are on the same shaft and the electric motor is cooled with the refrigerant. The performance of the centrifugal compressor is evaluated based on semi-empirical specific-speed curves and the effect of the Reynolds number, surface roughness and tip clearance have also been taken into account. The thermodynamic and transport properties of the working fluids are modelled with a real-gas model. The condensing and evaporation temperatures, the temperature after the flash Intercooler, and cooling power have been chosen as fixed values in the process. The aim is to gain a maximum coefficient of performance (COP). The method of optimisation, the operation of the compressor and flash Intercooler, and the method for estimating the electric motor cooling are also discussed in the article.

  • Optimising the refrigeration cycle with a two-stage centrifugal compressor and a flash Intercooler
    International Journal of Refrigeration, 2009
    Co-Authors: Pekka Röyttä, Teemu Turunen-saaresti, Juha Honkatukia
    Abstract:

    The optimisation of a refrigeration process with a two-stage centrifugal compressor and flash Intercooler is presented in this paper. The two-stage centrifugal compressor stages are on the same shaft and the electric motor is cooled with the refrigerant. The performance of the centrifugal compressor is evaluated based on semi-empirical specific-speed curves and the effect of the Reynolds number, surface roughness and tip clearance have also been taken into account. The thermodynamic and transport properties of the working fluids are modelled with a real-gas model. The condensing and evaporation temperatures, the temperature after the flash Intercooler, and cooling power have been chosen as fixed values in the process. The aim is to gain a maximum coefficient of performance (COP). The method of optimisation, the operation of the compressor and flash Intercooler, and the method for estimating the electric motor cooling are also discussed in the article. © 2009 Elsevier Ltd and IIR.

Pekka Röyttä - One of the best experts on this subject based on the ideXlab platform.

  • optimising the refrigeration cycle with a two stage centrifugal compressor and a flash Intercooler
    International Journal of Refrigeration-revue Internationale Du Froid, 2009
    Co-Authors: Pekka Röyttä, Teemu Turunensaaresti, Juha Honkatukia
    Abstract:

    The optimisation of a refrigeration process with a two-stage centrifugal compressor and flash Intercooler is presented in this paper. The two-stage centrifugal compressor stages are on the same shaft and the electric motor is cooled with the refrigerant. The performance of the centrifugal compressor is evaluated based on semi-empirical specific-speed curves and the effect of the Reynolds number, surface roughness and tip clearance have also been taken into account. The thermodynamic and transport properties of the working fluids are modelled with a real-gas model. The condensing and evaporation temperatures, the temperature after the flash Intercooler, and cooling power have been chosen as fixed values in the process. The aim is to gain a maximum coefficient of performance (COP). The method of optimisation, the operation of the compressor and flash Intercooler, and the method for estimating the electric motor cooling are also discussed in the article.

  • Optimising the refrigeration cycle with a two-stage centrifugal compressor and a flash Intercooler
    International Journal of Refrigeration, 2009
    Co-Authors: Pekka Röyttä, Teemu Turunen-saaresti, Juha Honkatukia
    Abstract:

    The optimisation of a refrigeration process with a two-stage centrifugal compressor and flash Intercooler is presented in this paper. The two-stage centrifugal compressor stages are on the same shaft and the electric motor is cooled with the refrigerant. The performance of the centrifugal compressor is evaluated based on semi-empirical specific-speed curves and the effect of the Reynolds number, surface roughness and tip clearance have also been taken into account. The thermodynamic and transport properties of the working fluids are modelled with a real-gas model. The condensing and evaporation temperatures, the temperature after the flash Intercooler, and cooling power have been chosen as fixed values in the process. The aim is to gain a maximum coefficient of performance (COP). The method of optimisation, the operation of the compressor and flash Intercooler, and the method for estimating the electric motor cooling are also discussed in the article. © 2009 Elsevier Ltd and IIR.

Shuying Li - One of the best experts on this subject based on the ideXlab platform.

  • Off-Design Behavior Analysis and Operating Curve Design of Marine Intercooled Gas Turbine
    Mathematical Problems in Engineering, 2017
    Co-Authors: Nian-kun Ji, Shuying Li, Zhitao Wang, Ningbo Zhao
    Abstract:

    The intercooled gas turbine obtained by adopting an indirect heat exchanger into an existing gas turbine is one of the candidates for developing high-power marine power units. To simplify such a strong coupled nonlinear system reasonably, the feasibility and availability of qualifying equivalent effectiveness as the only parameter to evaluate the Intercooler behavior are investigated. Regarding equivalent effectiveness as an additional degree of freedom, the steady state model of a marine intercooled gas turbine is developed and its off-design performance is analyzed. With comprehensive considerations given to various phase missions of ships, operational flexibility, mechanical constraints, and thermal constraints, the operating curve of the intercooled gas turbine is optimized based on graphical method in three-dimensional performance space. The resulting operating curve revealed that the control strategy at the steady state conditions for the intercooled gas turbine should be variable cycle control. The necessity of integration optimization design for gas turbine and Intercooler is indicated and the modeling and analysis method developed in this paper should be beneficial to it.

  • An Evaluation of the Application of Nanofluids in Intercooled Cycle Marine Gas Turbine Intercooler
    Journal of Engineering for Gas Turbines and Power-transactions of The Asme, 2015
    Co-Authors: Ningbo Zhao, Shuying Li
    Abstract:

    Coolant is one of the important factors affecting the overall performance of the Intercooler for the intercooled cycle marine gas turbine. Conventional coolants such as water and ethylene glycol have lower thermal conductivity which can hinder the development of highly effective compact Intercooler. Nanofluids that consist of nanoparticles and base fluids have superior properties like extensively higher thermal conductivity and heat transfer performance compared to those of base fluids. This paper focuses on the application of two different water-based nanofluids containing aluminum oxide (Al2O3) and copper (Cu) nanoparticles in intercooled cycle marine gas turbine Intercooler. The effectiveness-number of transfer unit method is used to evaluate the flow and heat transfer performance of Intercooler and the thermophysical properties of nanofluids are obtained from literature. Then the effects of some important parameters such as nanoparticle volume concentration, coolant Reynolds number, coolant inlet temperature and gas side operating parameters on the flow and heat transfer performance of Intercooler are discussed in detail. The results demonstrate that nanofluids have excellent heat transfer performance and need lower pumping power in comparison with base fluids under different gas turbine operating conditions. Under the same heat transfer, Cu-water nanofluids can reduce more pumping power than Al2O3-water nanofluids. It is also concluded that the overall performance of Intercooler can be enhanced when increasing the nanoparticle volume concentration and coolant Reynolds number and decreasing the coolant inlet temperature.Copyright © 2015 by ASME

  • Dynamic Time-Delay Characteristics and Structural Optimization Design of Marine Gas Turbine Intercooler
    Mathematical Problems in Engineering, 2014
    Co-Authors: Ningbo Zhao, Shuying Li
    Abstract:

    Aiming at the rapid mobility of marine gas turbine and the dynamic time-delay problem of Intercooler for intercooled cycle marine gas turbine, the dynamic simulation model of Intercooler was set up based on effectiveness-number of transfer units (-NTU) and lumped parameter method in this paper. The model comprehensively considers related physical properties dependent on temperature. Dynamic response characteristics of gas outlet temperature and pressure and coolant outlet temperature of Intercooler with different materials and coolants in the change of operation condition of marine gas turbine were analyzed in detail. Besides, this paper explored the use of simulated annealing algorithm for structural optimization of Intercooler. The results showed that both material and coolant were the significant factors that affected the heat transfer and dynamic performance of Intercooler. The heat transfer and dynamic performance of the Intercooler obtained by using simulated annealing algorithm were better than those of preliminary design.

  • Study on flow parameters optimisation for marine gas turbine Intercooler system based on simulation experiment
    Journal of Computer Applications in Technology, 2013
    Co-Authors: Yulong Ying, Shuying Li, Zhitao Wang
    Abstract:

    The thermodynamic calculation software of Intercooled-Cycle gas turbine was developed to observe the impacts that the environmental parameters and cold degrees of Intercooler produce quantitatively on this marine engine performance. And then, the mathematical model of intercooled-cycle gas turbine was established and the relative non-linear simulation model was also built based on MATLAB/SIMULINK to further study on flow parameters optimisation for marine gas turbine Intercooler. At last, under a given structure size of Intercooler, the impact of different liquid-side flow parameters on the Intercooler system performance was analysed based on simulation model. The simulation experimental results show that the increase in glycol-water solution flow rate and seawater flow rate can improve the performance of the intercooled-cycle gas turbine to a degree, but the rational flow rates should be chosen according to the atmospheric condition and seawater temperature, and the optimal regulation rule was got.

  • simulation study on fuel supply rate curve of marine inter cooled gas turbine
    International Conference on Modelling Identification and Control, 2012
    Co-Authors: Yulong Ying, Shuying Li, Zhitao Wang
    Abstract:

    The completely non-linear mathematical model of intercooled cycle gas turbine has been built according to the mechanism of thermal system modeling method, taking into account the impact on the gas turbine system such as rotational inertia, volume inertia, Intercooler thermal inertia, and the relative dynamic simulation of the intercooled cycle gas turbine based on Matlab/Simulink has also been built. Through the research of sub-linear fuel supply rate curve, the best fuel supply rate curve of the intercooled cycle gas turbine was obtained.

Lorenzo Winchler - One of the best experts on this subject based on the ideXlab platform.

  • Thermodynamic Analysis of an Organic Rankine Cycle for Waste Heat Recovery from an Aeroderivative Intercooled Gas Turbine
    Energy Procedia, 2016
    Co-Authors: Carlo Carcasci, Lorenzo Winchler
    Abstract:

    © 2016 The Authors. This paper presents a study of an Organic Rankine Cycle combined with an intercooled gas turbine: thermodynamic analyses are carried out using four different organic fluids (toluene, benzene, cyclopentane and cyclohexane). Organic Rankine Cycle can be combined with a gas turbine through a diathermic oil circuit in order to convert gas turbine waste heat into electrical power: ORC can be a promising choice for waste heat recovery at low/medium temperatures. An intercooled gas turbine is characterized by low exhaust temperature, and the Organic Rankine Cycle, that can work with lower temperature respect to a Rankine cycle, can be an interesting solution to improve the efficiency of the power plant. In an intercooled gas turbine with high pressure ratio, waste heat can be recovered from exhaust gas and also from the Intercooler: Air temperature exiting from the first compressor is about 160-220°C and it is generally cooled by water. This waste heat can be recovered by an Organic Rankine Cycle to convert the low-temperature heat source into mechanical energy and increase the global power plant efficiency.

Chi Hiep Le - One of the best experts on this subject based on the ideXlab platform.

  • Thermodynamic analysis of an ejector–vapour compressor cascade refrigeration system
    Journal of Thermal Analysis and Calorimetry, 2020
    Co-Authors: Trung Kien Nguyen, Chi Hiep Le
    Abstract:

    Using the framework of the first and second law of thermodynamics, an ejector–vapour compressor cascade refrigeration system is studied. The criteria for refrigerant selection are examined, with R134a and R410A selected as the refrigerant for the ejector and compressor sub-cycle, respectively. The effects of generator temperature, evaporator temperature, condenser temperature, Intercooler temperature and Intercooler temperature difference are examined. The results demonstrate that a combined cycle can improve 30.8% when compared to the COP of single compressor cycle and 122% when compared to the single ejector cycle. In addition, Intercooler temperature can be set at 26.5 °C for minimizing total exergy loss.