Sökning: "Mechanical engineering"

Visar resultat 1 - 5 av 4939 avhandlingar innehållade orden Mechanical engineering.

  1. 1. Distributed thermal response tests New insights on U-pipe and Coaxial heat exchangers in groundwater-filled boreholes

    Detta är en avhandling från Stockholm : KTH Royal Institute of Technology

    Författare :José Acuña; KTH.; [2013]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Borehole heat exchangers; Distributed Thermal Response Test; Ground Source Heat Pumps; Coaxial; U-pipe; Multi-pipe; Pipe-in-pipe; Multi-chamber; Groundwater; Thermosyphon; SRA - Energy; SRA - Energi;

    Sammanfattning : U-pipe Borehole Heat Exchangers (BHE) are widely used today in ground source heating and cooling systems in spite of their less than optimal performance. This thesis provides a better understanding on the function of U-pipe BHEs and Investigates alternative methods to reduce the temperature difference between the circulating fluid and the borehole wall, including one thermosyphon and three different types of coaxial BHEs. LÄS MER

  2. 2. On the Analysis of Energy Efficient Aircraft Engines

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :Oskar Thulin; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Performance modelling; Aero engine; Turbofan; Aircraft engine; Installed propulsion; Ultra high bypass ratio; Exergy analysis; Engine weight estimate; Variable area fan nozzle; Multiple pivoting flaps; Translating cowls;

    Sammanfattning : Aero engine performance analysis is highly multidimensional using various measures of component performance such as turbomachinery and mechanical efficiencies, and pressure loss coefficients. Using conventional performance analysis, relying on only the laws of thermodynamics, it is possible to understand how the performance parameters affect the component performance, but it is difficult to directly compare the magnitude of various loss sources. LÄS MER

  3. 3. Highly Dynamic Drives for Electric Hybrid Vehicles : Electric Machine Design and Dynamic Test Method

    Detta är en avhandling från Division of Industrial Electrical Engineering and Automation, Faculty of Engineering, Lund University

    Författare :Yury Loayza Vargas; Lunds universitet.; Lund University.; [2017-09-20]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric Hybrid Vehicles; Electric Machine Design; Dynamic Testing; Dynamic loading; Synthetic Loading; FPGA; Torque Measurement; Field weakening controller FWC ; IPMSM; FEMM; LabVIEW; Dynamic Testing Technique; Dynamic Test Method; CompactRIO;

    Sammanfattning : Electric Hybrid Vehicles (EHVs) play a crucial role in the development towardsa more environmental friendly transportation. An alternative to solve someactual challenges with hybridization of vehicles is studied at the Division ofIndustrial Electrical Engineering and Automation (IEA) at Lund Universityin cooperation with the automotive industry. LÄS MER

  4. 4. Control Aspects of Complex Hydromechanical Transmissions with a Focus on Displacement Control

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :L. Viktor Larsson; Linköpings universitet.; Linköpings universitet.; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis deals with control aspects of complex hydromechanical transmissions. The overall purpose is to increase the knowledge of important aspects to consider during the development of hydromechanical transmissions to ensure transmission functionality. LÄS MER

  5. 5. Coated Ferritic Stainless Steels as Interconnects in Solid Oxide Fuel Cells - Material Development and Electrical Properties

    Detta är en avhandling från Linköping : Linköping University Electronic Press

    Författare :Jan Gustav Grolig; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; SOFC; High Temperature Corrosion; ASR; Interconnects;

    Sammanfattning : Solid oxide fuel cells (SOFCs) are attracting increasing interest as devices with potentialuses in decentralized and clean electricity and heat production. Several challengeswith respect to materials have to be overcome to achieve efficiencies and life-spansthat are sufficient for long-term applications. LÄS MER