The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform

Xiao He-lin - One of the best experts on this subject based on the ideXlab platform.

Chatchai Sirisamphanwong - One of the best experts on this subject based on the ideXlab platform.

  • Investigations to Conduct a Study about Possibilities to Use Small Scale Solar Dish Stirling Engine System in Thailand
    Energy Procedia, 2014
    Co-Authors: Kongrit Mansiri, Sukruedee Sukchai, Chatchai Sirisamphanwong
    Abstract:

    Abstract This research studies the possibilities of generating electricity by using small scale solar dish Stirling Engine System in Thailand. A solar dish Stirling Engine System was evaluated and designed as prototypes for Thailand . The performance of System for electricity generation was also simulated under Thai climate condition. The results of the study can be structured in two parts. First is testing the existing Stirling Engine and second is simulation the electricity generation by solar dish Stirling Engine System prototype in Thailand. The existing Stirling Engine at the Komplexlabor of the FH – Stralsund University, Germany was tested to understand the characteristics of the operating System. Stirling Engine was operated at temperature of about 800 o C in the combustion chamber, being its nominal rotational speed 1,517 rpm. Finally, the average Stirling Engine efficiency was established in 22%. The results of simulation on solar dish Stirling Engine were that the main components for a prototype of a solar dish Stirling Engine System in Thailand shall consist of a Stirling Engine with a nominal power of 25 kW, and a 131 m 2 dish concentrator. It can generate electricity about 27,946 kWh/year of electricity under Thai climate condition. During the working process, the heat lost on dish concentrator was 22% and heat lost within the Stirling Engine was 60.84%. The System efficiency of this solar dish Stirling Engine System was 17%.

Seungbok Choi - One of the best experts on this subject based on the ideXlab platform.

  • vibration control of a ship Engine System using high load magnetorheological mounts associated with a new indirect fuzzy sliding mode controller
    Smart Materials and Structures, 2015
    Co-Authors: Do Xuan Phu, Seungbok Choi
    Abstract:

    In this work, a new high-load magnetorheological (MR) fluid mount System is devised and applied to control vibration in a ship Engine. In the investigation of vibration-control performance, a new modified indirect fuzzy sliding mode controller is formulated and realized. The design of the proposed MR mount is based on the flow mode of MR fluid, and it includes two separated coils for generating a magnetic field. An optimization process is carried out to achieve maximal damping force under certain design constraints, such as the allowable height of the mount. As an actuating smart fluid, a new plate-like iron-particle-based MR fluid is used, instead of the conventional spherical iron-particle-based MR fluid. After evaluating the field-dependent yield stress of the MR fluid, the field-dependent damping force required to control unwanted vibration in the ship Engine is determined. Subsequently, an appropriate-sized MR mount is manufactured and its damping characteristics are evaluated. After confirming the sufficient damping force level of the manufactured MR mount, a medium-sized ship Engine mount System consisting of eight MR mounts is established, and its dynamic governing equations are derived. A new modified indirect fuzzy sliding mode controller is then formulated and applied to the Engine mount System. The displacement and velocity responses show that the unwanted vibrations of the ship Engine System can be effectively controlled in both the axial and radial directions by applying the proposed control methodology.

Tianju Liao - One of the best experts on this subject based on the ideXlab platform.

  • optimum performance characteristics of a solar driven stirling heat Engine System
    Energy Conversion and Management, 2015
    Co-Authors: Tianju Liao
    Abstract:

    Abstract A solar-driven Stirling heat Engine System composed of a Stirling heat Engine, a solar collector, and a heat sink is presented, in which the radiation and convection heat losses of the solar collector, the heat-leak between the thermal absorber and heat sink, the regenerative losses of the Stirling heat Engine, and the energy balance between the thermal absorber and the high isothermal process of the Stirling heat Engine are taken into consideration. Based on the irreversible thermodynamics and Lagrange multiplier method, the maximum power output and the corresponding optimal efficiency of the System are determined and the absorber temperature that maximizes the optimal System efficiency is calculated numerically. The influences of some System parameters such as the concentrating ratio, the volume ratio during the regenerative processes and irreversibilities of heat exchange processes on the optimal efficiency are analyzed in details. The results obtained here may provide a new idea to design practical solar-driven Stirling heat Engine System.

Lyman J. Petrosky - One of the best experts on this subject based on the ideXlab platform.

  • Nuclear Engine System Simulation (NESS). Volume 1: Program user's guide
    1993
    Co-Authors: Dennis G. Pelaccio, Christine M. Scheil, Lyman J. Petrosky
    Abstract:

    A Nuclear Thermal Propulsion (NTP) Engine System design analysis tool is required to support current and future Space Exploration Initiative (SEI) propulsion and vehicle design studies. Currently available NTP Engine design models are those developed during the NERVA program in the 1960's and early 1970's and are highly unique to that design or are modifications of current liquid propulsion System design models. To date, NTP Engine-based liquid design models lack integrated design of key NTP Engine design features in the areas of reactor, shielding, multi-propellant capability, and multi-redundant pump feed fuel Systems. Additionally, since the SEI effort is in the initial development stage, a robust, verified NTP analysis design tool could be of great use to the community. This effort developed an NTP Engine System design analysis program (tool), known as the Nuclear Engine System Simulation (NESS) program, to support ongoing and future Engine System and stage design study efforts. In this effort, Science Applications International Corporation's (SAIC) NTP version of the Expanded Liquid Engine Simulation (ELES) program was modified extensively to include Westinghouse Electric Corporation's near-term solid-core reactor design model. The ELES program has extensive capability to conduct preliminary System design analysis of liquid rocket Systems and vehicles. The program is modular in nature and is versatile in terms of modeling state-of-the-art component and System options as discussed. The Westinghouse reactor design model, which was integrated in the NESS program, is based on the near-term solid-core ENABLER NTP reactor design concept. This program is now capable of accurately modeling (characterizing) a complete near-term solid-core NTP Engine System in great detail, for a number of design options, in an efficient manner. The following discussion summarizes the overall analysis methodology, key assumptions, and capabilities associated with the NESS presents an example problem, and compares the results to related NTP Engine System designs. Initial installation instructions and program disks are in Volume 2 of the NESS Program User's Guide.

  • Nuclear Engine System Simulation (NESS). Version 2.0: Program user's guide
    1993
    Co-Authors: Dennis G. Pelaccio, Christine M. Scheil, Lyman J. Petrosky
    Abstract:

    This Program User's Guide discusses the Nuclear Thermal Propulsion (NTP) Engine System design features and capabilities modeled in the Nuclear Engine System Simulation (NESS): Version 2.0 program (referred to as NESS throughout the remainder of this document), as well as its operation. NESS was upgraded to include many new modeling capabilities not available in the original version delivered to NASA LeRC in Dec. 1991, NESS's new features include the following: (1) an improved input format; (2) an advanced solid-core NERVA-type reactor System model (ENABLER 2); (3) a bleed-cycle Engine System option; (4) an axial-turbopump design option; (5) an automated pump-out turbopump assembly sizing option; (6) an off-design gas generator Engine cycle design option; (7) updated hydrogen properties; (8) an improved output format; and (9) personal computer operation capability. Sample design cases are presented in the user's guide that demonstrate many of the new features associated with this upgraded version of NESS, as well as design modeling features associated with the original version of NESS.

  • Nuclear Engine System Simulation (NESS). Volume 1: Program user's guide. Final Report
    1993
    Co-Authors: Dennis G. Pelaccio, Christine M. Scheil, Lyman J. Petrosky
    Abstract:

    A Nuclear Thermal Propulsion (NTP) Engine System design analysis tool is required to support current and future Space Exploration Initiative (SEI) propulsion and vehicle design studies. Currently available NTP Engine design models are those developed during the NERVA program in the 1960's and early 1970's and are highly unique to that design or are modifications of current liquid propulsion System design models. To date, NTP Engine-based liquid design models lack integrated design of key NTP Engine design features in the areas of reactor, shielding, multi-propellant capability, and multi-redundant pump feed fuel Systems. Additionally, since the SEI effort is in the initial development stage, a robust, verified NTP analysis design tool could be of great use to the community. This effort developed an NTP Engine System design analysis program (tool), known as the Nuclear Engine System Simulation (NESS) program, to support ongoing and future Engine System and stage design study efforts. In this effort, Science Applications International Corporation's (SAIC) NTP version of the Expanded Liquid Engine Simulation (ELES) program was modified extensively to include Westinghouse Electric Corporation's near-term solid-core reactor design model. The ELES program has extensive capability to conduct preliminary System design analysis of liquid rocket Systems and vehicles. Themore » program is modular in nature and is versatile in terms of modeling state-of-the-art component and System options as discussed. The Westinghouse reactor design model, which was integrated in the NESS program, is based on the near-term solid-core ENABLER NTP reactor design concept. This program is now capable of accurately modeling (characterizing) a complete near-term solid-core NTP Engine System in great detail, for a number of design options, in an efficient manner.« less

  • Nuclear Engine System simulation (NESS) program update
    AIP Conference Proceedings, 1993
    Co-Authors: Christine M. Scheil, Dennis G. Pelaccio, Lyman J. Petrosky
    Abstract:

    The second phase of development of a Nuclear Thermal Propulsion (NTP) Engine System design analysis code has been completed. The standalone, versatile Nuclear Engine System Simulation (NESS) code provides an accurate, detailed assessment of Engine System operating performance, weight, and sizes. The critical information is required to support ongoing and future Engine System and stage design study efforts. This recent development effort included incorporation of an updated solid‐core nuclear thermal reactor model that yields a reduced core weight and higher fuel power density when compared to a NERVA type reactor. NESS can now analyze expander, gas generator, and bleed cycles, along with multi‐redundant propellant pump feed Systems. Performance and weight of efficient multi‐stage axial turbopump can now be determined, in addition to the traditional centrifugal pump.Key code outputs include reactor operating charactertistics and weights and well as Engine System parameters such as performance, weights, dimensions, pressures, temperatures, mass flows and turbopump operating characteristics for both design and off‐design operating conditions. Representative NTP Engine System designs are also shown. An overview of NESS methodology and capabilities is presented in this paper, with special emphasis being placed on recent code developments.The second phase of development of a Nuclear Thermal Propulsion (NTP) Engine System design analysis code has been completed. The standalone, versatile Nuclear Engine System Simulation (NESS) code provides an accurate, detailed assessment of Engine System operating performance, weight, and sizes. The critical information is required to support ongoing and future Engine System and stage design study efforts. This recent development effort included incorporation of an updated solid‐core nuclear thermal reactor model that yields a reduced core weight and higher fuel power density when compared to a NERVA type reactor. NESS can now analyze expander, gas generator, and bleed cycles, along with multi‐redundant propellant pump feed Systems. Performance and weight of efficient multi‐stage axial turbopump can now be determined, in addition to the traditional centrifugal pump.Key code outputs include reactor operating charactertistics and weights and well as Engine System parameters such as performance, weights, dim...

  • Nuclear Engine System Simulation (NESS) version 2.0
    1993
    Co-Authors: Dennis G. Pelaccio, Christine M. Scheil, Lyman J. Petrosky
    Abstract:

    The topics are presented in viewgraph form and include the following; nuclear thermal propulsion (NTP) Engine System analysis program development; nuclear thermal propulsion Engine analysis capability requirements; team resources used to support NESS development; expanded liquid Engine simulations (ELES) computer model; ELES verification examples; NESS program development evolution; past NTP ELES analysis code modifications and verifications; general NTP Engine System features modeled by NESS; representative NTP expander, gas generator, and bleed Engine System cycles modeled by NESS; NESS program overview; NESS program flow logic; enabler (NERVA type) nuclear thermal rocket Engine; prismatic fuel elements and supports; reactor fuel and support element parameters; reactor parameters as a function of thrust level; internal shield sizing; and reactor thermal model.