Sökning: "turbulensmodeller"

Visar resultat 1 - 5 av 8 avhandlingar innehållade ordet turbulensmodeller.

  1. 1. A Study of the Swirling Flow Pattern when Using TurboSwirl in the Casting Process

    Författare :Haitong Bai; Mikael Ersson; Pär Jönsson; Yogeshwar Sahai; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; flow pattern; swirling flow; TurboSwirl; CFD; turbulence models; water model; flödesmönster; roterandeflöde; TurboSwirl; CFD; turbulensmodeller; vattenmodell; Metallurgical process science; Metallurgisk processvetenskap;

    Sammanfattning : The use of a swirling flow can provide a more uniform velocity distribution and a calmer filling condition according to previous studies of both ingot and continuous casting processes of steel. However, the existing swirling flow generation methods developed in last decades all have some limitations. LÄS MER

  3. 2. Estimation of Thermal and Hydraulic Characteristics of Compact Brazed Plate Heat Exchangers

    Författare :Vijaya Sekhar Gullapalli; Institutionen för energivetenskaper; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brazed plate heat exchangers; CFD; heat transfer; pressure drop; heat exchanger selection software; transcritical-CO2 calculations; heat exchanger rating; evaporation; condensation; refrigerant properties; discretized calculations;

    Sammanfattning : This thesis work presents various performance estimation methods of compact brazed plate heat exchangers (BPHE) operating in single phase, condenser, evaporator, cascaded and transcritical applications. Such methods play a vital role in development of heat exchanger selection software and during geometry parameter estimation in the new product development process. LÄS MER

  4. 3. Coherent structures and control in wall-bounded turbulent flows

    Författare :Marco Atzori; Philipp Schlatter; Ricardo Vinuesa; Oscar Flores; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulent boundary layers; numerical simulations; coherent structures; predetermined flow control.; Turbulenta gränsskikt; numeriska simuleringar; koherenta strukturer; förutbestämd flödeskontroll; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : This thesis is concerned with two distinct topics related to the study of wall-bounded turbulence: the connection between instantaneous three-dimensional coherent structures and mean-flow properties, and the development and analysis of pre-determined control techniques for adverse-pressure-gradient boundary layers.We examined regions with intense velocity fluctuations in various flowcases. LÄS MER

  5. 4. Time, space and control: deep-learning applications to turbulent flows

    Författare :Luca Guastoni; Ricardo Vinuesa; Hossein Azizpour; Philipp Schlatter; Andrea Beck; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbulence; deep learning; deep reinforcement learning; flow control; turbulens; djupinlärning; djupförstärkningsinlärning; flödeskontroll; Teknisk mekanik; Engineering Mechanics;

    Sammanfattning : In the present thesis, the application of deep learning and deep reinforcement learning to turbulent-flow simulations is investigated. Deep-learning models are trained to perform temporal and spatial predictions, while deep reinforcement learning is applied to a flow-control problem, namely the reduction of drag in an open channel flow. LÄS MER

  7. 5. Design of Internal Cooling Passages: Investigation of Thermal Performance of Serpentine Passages

    Författare :Waseem Siddique; Torsten Fransson; Bengt Sundén; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Gas turbine; heat transfer; CFD; Serpentine passages; SRA - Energy; SRA - Energi;

    Sammanfattning : Gas turbines are used to convert thermal energy into mechanical energy. The thermal efficiency of the gas turbine is directly related to the turbine inlet temperature. LÄS MER