The Experts below are selected from a list of 100404 Experts worldwide ranked by ideXlab platform

Huili Zhang - One of the best experts on this subject based on the ideXlab platform.

  • energy analysis of a particle suspension solar Combined cycle power plant
    Energy Conversion and Management, 2018
    Co-Authors: Qian Kang, Raf Dewil, Jan Degreve, Jan Baeyens, Huili Zhang
    Abstract:

    Abstract The key to achieve an economically more attractive concentrated solar power plant is to work at higher operating temperatures, allowing both higher power conversion efficiencies resulting in a smaller heliostat field for a given energy output, and higher temperature ranges in the storage tanks, with increased energy storage density and smaller size, hence less expensive. This fostered the development of using particle suspensions as heat transfer media. This paper presents a theoretical framework for the energy analysis of a particle-in-tube solar power plant, hybridized, with topping Air-Brayton cycle turbine, and bottoming steam block. From studying the effects of essential design parameters on the energy efficiency, the heat transfer efficiency of the turbine Air preheater is of paramount importance to increase the solar contribution within the hybrid concept, while the energy efficiency moreover increases by an optimum Air-Brayton cycle turbine operation (mostly through the pressure ratio, less by the operating temperature). The overall efficiency of the concept varies from about 40% when using Combined low and high pressure Brayton cycle turbines only, to over 48% in a fully Combined Air-steam concept. Energy efficiency findings are in agreement with the literature data.

Caroline S.b. Fitzpatrick - One of the best experts on this subject based on the ideXlab platform.

  • Spectral analysis of pressure variations during Combined Air and water backwash of rapid gravity filters
    Water Research, 1999
    Co-Authors: David J. Hall, Caroline S.b. Fitzpatrick
    Abstract:

    Abstract Simultaneous water and Air backwashing has been established as the most effective cleaning regime for rapid gravity filters. For certain Air and water wash rates the bed can reach a state termed “collapse-pulsing”. This has been identified as the optimum cleaning regime for simultaneous Air and water backwashing. An empirical formula exists to predict collapse-pulsing, this is given in terms of the water, Air and minimum fluidising velocities. However, no suitable method exists to confirm that the collapse-pulsing condition has been achieved, other than by visually subjective observations of the bed. Visual observation is not always physically possible or practical on industrial size filters. This study examines pressure fluctuations, taken at various heights in the bed, and their associated frequency spectra as a means of identifying the collapse-pulsing condition. Preliminary results show that, particularly in the upper sections of the bed, distinct peaks occurs in the frequency spectrum at collapse-pulsing.

  • Pressure signal analysis of Combined water and Air backwash of rapid gravity filters
    Water Research, 1997
    Co-Authors: David G. Hemmings, Caroline S.b. Fitzpatrick
    Abstract:

    Abstract Many problems encountered in water filtration are associated with the effectiveness of backwashing. Combined Air and water backwashing especially using flow rate combinations resulting in “collapse-pulsing” provide the most effective cleaning. This study examines a technique of analysing pressure signal fluctuations in order to determine the onset of “collapse-pulsing”. The technique provides a non-subjective and practical method of “collapse-pulsing” determination. The resultant pressure fluctuation traces are examined in combination with headloss versus water velocity profiles at particular set Air flow rates. The occurrence of significant fluctuation patterns at the position where headloss becomes constant implies that “collapse-pulsing” determined by this technique is the onset of three phase fluidisation.

Qian Kang - One of the best experts on this subject based on the ideXlab platform.

  • energy analysis of a particle suspension solar Combined cycle power plant
    Energy Conversion and Management, 2018
    Co-Authors: Qian Kang, Raf Dewil, Jan Degreve, Jan Baeyens, Huili Zhang
    Abstract:

    Abstract The key to achieve an economically more attractive concentrated solar power plant is to work at higher operating temperatures, allowing both higher power conversion efficiencies resulting in a smaller heliostat field for a given energy output, and higher temperature ranges in the storage tanks, with increased energy storage density and smaller size, hence less expensive. This fostered the development of using particle suspensions as heat transfer media. This paper presents a theoretical framework for the energy analysis of a particle-in-tube solar power plant, hybridized, with topping Air-Brayton cycle turbine, and bottoming steam block. From studying the effects of essential design parameters on the energy efficiency, the heat transfer efficiency of the turbine Air preheater is of paramount importance to increase the solar contribution within the hybrid concept, while the energy efficiency moreover increases by an optimum Air-Brayton cycle turbine operation (mostly through the pressure ratio, less by the operating temperature). The overall efficiency of the concept varies from about 40% when using Combined low and high pressure Brayton cycle turbines only, to over 48% in a fully Combined Air-steam concept. Energy efficiency findings are in agreement with the literature data.

Xing Fang - One of the best experts on this subject based on the ideXlab platform.

  • control and energy simulation of variable refrigerant flow Air conditioning system Combined with outdoor Air processing unit
    Applied Thermal Engineering, 2014
    Co-Authors: Yonghua Zhu, Xinqiao Jin, Xing Fang, Bo Fan
    Abstract:

    A variable refrigerant flow (VRF) unit and outdoor Air (OA) processing unit Combined Air conditioning system is proposed as a solution for ventilation problems in VRF systems. System structure and control strategies are addressed. Simulation platform is established based on component and sub-system models developed. Control and energy performances analysis are then put forward under various conditions. It is found that the Combined system could maintain all the zones at their specific set-points within small errors no matter set-points of the zones are the same or different. In addition, indoor Air quality can be ensured. Energy efficiency characteristics of the Combined system are greatly affected by the OA supply temperature of the OA processing unit, which opens up the opportunity of minimizing the energy consumption of the Combined system through optimal control strategy. Results reveal that the best OA supply temperature can be obtained through optimizing part load ratio of the OA processing unit to a range in which the system operates with high efficiency.

  • simulation of variable refrigerant flow Air conditioning system in heating mode Combined with outdoor Air processing unit
    Energy and Buildings, 2014
    Co-Authors: Yonghua Zhu, Xinqiao Jin, Bo Fan, Xing Fang
    Abstract:

    Variable refrigerant flow (VRF) Air conditioning system has become attractive due to better energy performances than traditional Air conditioning systems. However, the shortcoming of no outdoor Air (OA) intake has not been solved thoroughly. A new VRF and outdoor Air processing unit Combined Air conditioning system is proposed and simulated. The first obstacle is that there is no well-known simulation tool for VRF unit in heating mode. A VRF model of condenser-number independence is developed and validated first. The Combined system is modeled by integrating the individual sub-system or component models into a complete system. The average error of the developed model to predict heating capacity, input power and COP are 7.87%, 12.45% and 6.19% respectively. Finally the Combined system is simulated under conditions of the same and different set-points of the Air conditioning zones. The Combined system could maintain all the zones at their specific set-points within small errors no matter the set-points are the same or different. Moreover, indoor Air quality can be ensured. The demand of one Air conditioning system possessing independent units serving separate zones in the same building could be met by the Combined system.

Bo Fan - One of the best experts on this subject based on the ideXlab platform.

  • control and energy simulation of variable refrigerant flow Air conditioning system Combined with outdoor Air processing unit
    Applied Thermal Engineering, 2014
    Co-Authors: Yonghua Zhu, Xinqiao Jin, Xing Fang, Bo Fan
    Abstract:

    A variable refrigerant flow (VRF) unit and outdoor Air (OA) processing unit Combined Air conditioning system is proposed as a solution for ventilation problems in VRF systems. System structure and control strategies are addressed. Simulation platform is established based on component and sub-system models developed. Control and energy performances analysis are then put forward under various conditions. It is found that the Combined system could maintain all the zones at their specific set-points within small errors no matter set-points of the zones are the same or different. In addition, indoor Air quality can be ensured. Energy efficiency characteristics of the Combined system are greatly affected by the OA supply temperature of the OA processing unit, which opens up the opportunity of minimizing the energy consumption of the Combined system through optimal control strategy. Results reveal that the best OA supply temperature can be obtained through optimizing part load ratio of the OA processing unit to a range in which the system operates with high efficiency.

  • simulation of variable refrigerant flow Air conditioning system in heating mode Combined with outdoor Air processing unit
    Energy and Buildings, 2014
    Co-Authors: Yonghua Zhu, Xinqiao Jin, Bo Fan, Xing Fang
    Abstract:

    Variable refrigerant flow (VRF) Air conditioning system has become attractive due to better energy performances than traditional Air conditioning systems. However, the shortcoming of no outdoor Air (OA) intake has not been solved thoroughly. A new VRF and outdoor Air processing unit Combined Air conditioning system is proposed and simulated. The first obstacle is that there is no well-known simulation tool for VRF unit in heating mode. A VRF model of condenser-number independence is developed and validated first. The Combined system is modeled by integrating the individual sub-system or component models into a complete system. The average error of the developed model to predict heating capacity, input power and COP are 7.87%, 12.45% and 6.19% respectively. Finally the Combined system is simulated under conditions of the same and different set-points of the Air conditioning zones. The Combined system could maintain all the zones at their specific set-points within small errors no matter the set-points are the same or different. Moreover, indoor Air quality can be ensured. The demand of one Air conditioning system possessing independent units serving separate zones in the same building could be met by the Combined system.