Sökning: "Michel Cervantes"

Visar resultat 11 - 15 av 20 avhandlingar innehållade orden Michel Cervantes.

  1. 11. Development of the pressure-time method: final integration point and head losses

    Författare :Mehrdad Kalantar Neyestanaki; Michel Cervantes; Jonathan Nicolle; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pressure-time method; head loss calculation; endpoint determination; Strömningslära; Fluid Mechanics;

    Sammanfattning : Hydropower is an efficient renewable energy source able to regulate electrical grid fluctuations. However, many hydropower plants were built decades ago, and now it is the time for a major refurbishment. The turbine's efficiency is essential and needs to be determined before and after refurbishment. LÄS MER

  3. 12. Extension of the Pressure Time Method to 3-Dimensional Flows

    Författare :Mehrdad Kalantar Neyestanaki; Michel Cervantes; Pontus Jonsson; Georgiana Dunca; Thomas Staubli; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Sammanfattning : Hydropower has stood as a clean and sustainable energy source since the late 19th century. Many turbines were built 50 to 70 years ago and require refurbishment. It is important to assess the efficiency of turbines before and after refurbishment to meet performance guarantees .However, the flow rate makes such estimation challenging. LÄS MER

  4. 13. Numerical investigation of the flow and instabilities at part-load and speed-no-load in an axial turbine

    Författare :Jelle Kranenbarg; Michel Cervantes; Lisa Prahl Wittberg; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Speed-no-load; vortical flow structures; flow instabilities; rotating stall; mitigation; independent guide vanes; axial turbine; swirling flow; off design operation; URANS; parametric study; blade clearance; head losses; diffusor; GEKO model; flow separation; hydraulic turbine; Strömningslära; Fluid Mechanics;

    Sammanfattning : Global renewable energy requirements rapidly increase with the transition to a fossil-free society. As a result, intermittent energy resources, such as wind- and solar power, have become increasingly popular. However, their energy production varies over time, both in the short- and long term. LÄS MER

  5. 14. Development of the Pressure-Time Method for Flow Rate Measurement in Hydropower Plants by Numerical Simulation

    Författare :Simindokht Saemi; Michel Cervantes; Thomas Staubli; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

    Sammanfattning : Hydropower is a clean and sustainable energy resource developed since the late 19th century. To specify the hydraulic performance characteristics of hydraulic turbines, the volumetric flow rate as one of the few basic quantities should be determined. Discharge represents the most difficult quantity to measure. LÄS MER

  7. 15. Time dependent flow of biolubricant and suspended particles behavior within total hip replacement

    Författare :Alaleh Safari; Nazanin Emami; Michel Cervantes; Maria-Pau Ginebra; Zhongmin Jin; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Maskinelement; Machine Elements;

    Sammanfattning : Total hip replacement (THR) has been one of the most successful surgeries in the 21st century. Ultra-high-molecular-weight-polyethylene (UHMWPE) shows favorable mechanical and tribological properties when used as a bearing surface material in THR. However, produced UHMWPE wear particles challenge increasing the THR lifetimes. LÄS MER