Sökning: "energy transfer"

Visar resultat 11 - 15 av 1132 avhandlingar innehållade orden energy transfer.

  1. 11. Novel Approaches for Retrofitting Heat Exchanger Networks Subject to Varying Operating Conditions

    Författare :Christian Langner; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multi-Period Optimization; Flexibility; Critical Points; Feasibility; Heat Integration; Process Industry; Energy Efficiency; Retrofit;

    Sammanfattning : The process industry is responsible for a significant share of the final industrial energy use in Sweden. In particular, the pulp and paper industry accounts for more than 50 %. In this context, a number of studies have shown that there is a substantial potential for energy savings in the pulp and paper industry. LÄS MER

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

    Författare :José Acuña; Björn Palm; Jeffrey Spitler; KTH; []
    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

  4. 13. Fluid Flow and Heat Transfer Simulations for Complex Industrial Applications : From Reynolds Averaged Navier-Stokes towards Smoothed Particle Hydrodynamics

    Författare :Md Lokman Hosain; Rebei Bel Fdhila; Konstantinos Kyprianidis; Erik Dahlquist; Hailong Li; Moncho Gomez Gesteira; Mälardalens högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Computational Fluid Dynamics; Heat transfer; Industrial applications; Reynolds Averaged Navier-Stokes; Smoothed Particle Hydrodynamics; Energy enginnering; Thermal Management; Process control; Energy- and Environmental Engineering; energi- och miljöteknik;

    Sammanfattning : Optimal process control can significantly enhance energy efficiency of heating and cooling processes in many industries. Process control systems typically rely on measurements and so called grey or black box models that are based mainly on empirical correlations, in which the transient characteristics and their influence on the control parameters are often ignored. LÄS MER

  5. 14. The Heterocysts of Nostoc punctiforme : From Proteomics to Energy Transfer

    Författare :Tanai Cardona; Ann Magnuson; Matthias Rögner; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nostoc punctiforme; heterocyst; photosynthesis; thylakoid; isolation; proteomics; photosystem; energy transfer; hydrogen; Biochemistry; Biokemi; biokemi; Biochemistry;

    Sammanfattning : The aim of this thesis is to provide a thorough characterization of the photosynthetic machinery from the heterocysts of Nostoc punctiforme strain ATCC 29133. In this thesis I describe the protocols I have optimized for the isolation of thylakoids from vegetative cells, the purification of heterocysts and the isolation of thylakoids from the purified heterocysts. LÄS MER

  7. 15. Numerical predictions of heat-transfer applied to electrical machines

    Författare :Kristian Rönnberg; Christophe Duwig; Anders Dahlkild; Luca Peretti; Jens Honore Walther; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electric machines; energy efficiency; heat transfer; thermal management; high fidelity simulation; computational fluid dynamics CFD ; proper orthogonal decomposition POD ; lumped parameter thermal network LPTN ; Elektriska maskiner; energieffektivitet; verkningsgrad; värmeöverföring; värmehantering; simuleringar med hög upplösning; strömningsmekaniska beräkningar; proper orthogonal decomposition POD ; termiska nätverk; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : In order to meet the need for increased electrification, and at the same time reduce the total demand for electric energy, behavior change and technological innovation is needed. Over the decades power density of electric motors have increased, leading to increased demands on the cooling system design and performance. LÄS MER