The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Juha Honkatukia - One of the best experts on this subject based on the ideXlab platform.
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optimising the refrigeration cycle with a two stage centrifugal compressor and a flash intercooler
International Journal of Refrigeration-revue Internationale Du Froid, 2009Co-Authors: Pekka Röyttä, Teemu Turunensaaresti, Juha HonkatukiaAbstract: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.
Chi Hiep Le - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic analysis of an ejector–vapour compressor cascade refrigeration system
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Trung Kien Nguyen, Chi Hiep LeAbstract: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.
Shuying Li - One of the best experts on this subject based on the ideXlab platform.
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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, 2015Co-Authors: Ningbo Zhao, Shuying LiAbstract: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
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Dynamic Time-Delay Characteristics and Structural Optimization Design of Marine Gas Turbine Intercooler
Mathematical Problems in Engineering, 2014Co-Authors: Ningbo Zhao, Shuying LiAbstract: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.
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Study on flow parameters optimisation for marine gas turbine intercooler system based on simulation experiment
Journal of Computer Applications in Technology, 2013Co-Authors: Yulong Ying, Shuying Li, Zhitao WangAbstract: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.
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Optimal analysis of flow parameters for marine gas turbine intercooler based on simulation model
2012Co-Authors: Yulong Ying, Shuying Li, Zhitao WangAbstract:The mathematical model of intercooled cycle gas turbine was established and the relative simulation model was also built based on MATLAB/SIMULINK. Under a given structure size of intercooler, many magnificent conclusions were drawn over the analyses of influence of different liquid side flow parameters on the intercooler system performance. The simulation experimental results show the increase of glycol water flow and seawater flow can improve the performance of intercooler, but the performance isn't better as the flow of glycol water and seawater is larger. The rational flow rates should be chosen according to flow conditions. The influence of seawater inlet temperature on intercooler efficiency is significant and need to be considered in the optimal design.
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Optimization of Advanced Cycle Gas Turbine Intercooler Structure Based on Genetic Algorithm
Advanced Materials Research, 2011Co-Authors: Zhitao Wang, Shuying LiAbstract:As an important component of intercooled cycle gas turbine, intercooler directly affects the ratio power, thermal efficiency and various situation quality of gas turbine system. In this paper, efficiency-heat transfer units were used for the design of intercooler, and the structure parameters were optimized by genetic algorithm. The optimization results show that under the condition of required heat load and allowable pressure drop, the heat exchanger can be guaranteed as the smaller weight and the larger heat transfer efficiency, which can offer reference for the design of the actual intercooler.
Pekka Röyttä - One of the best experts on this subject based on the ideXlab platform.
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optimising the refrigeration cycle with a two stage centrifugal compressor and a flash intercooler
International Journal of Refrigeration-revue Internationale Du Froid, 2009Co-Authors: Pekka Röyttä, Teemu Turunensaaresti, Juha HonkatukiaAbstract: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.
Trung Kien Nguyen - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamic analysis of an ejector–vapour compressor cascade refrigeration system
Journal of Thermal Analysis and Calorimetry, 2020Co-Authors: Trung Kien Nguyen, Chi Hiep LeAbstract: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.