Sökning: "full-scale field experiments"

Visar resultat 1 - 5 av 43 avhandlingar innehållade orden full-scale field experiments.

1. 1. Out-of-Round Railway Wheels - Causes and Consequences An Investigation Including Field Tests, Out-of-Roundness Measurements and Numerical Simulations

   Författare :Anders Johansson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polygonalization; wheel flat; full-scale measurements; wear modelling; impact load detector; railway wheel out-of-roundness; wheel removal criterion; dynamic train-track interaction; corrugation;

   Sammanfattning : Causes and consequences of out-of-round railway wheels are investigated through literature studies, full-scale field experiments, out-of-roundness measurements, and numerical simulations. Both defects around the complete wheel circumference (e.g. polygonal wheels with wavelengths up to one wheel circumference) and local defects (e. LÄS MER

3. 2. Railway Wheel Flats. Martensite Formation, Residual Stresses, and Crack Propagation

   Författare :Johan Jergeus; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sliding contact; metallographic investigation; crack propagation; thermal shock; constitutive modelling; phase transformations; railway wheel flats; full-scale field experiments; transformation plasticity; tread damage; residual stresses; spalling; martensite formation;

   Sammanfattning : A railway wheel flat is a flat spot on the rolling surface of a wheel caused by its unintentional sliding on the rail. The reason for the sliding may be poorly adjusted, frozen or defect brakes, or too high braking forces in relation to the available wheel/rail adhesion. LÄS MER

4. 3. On some Fatigue Problems Related to Steel Bridges

   Författare :Roberto Crocetti; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; modular bridge expansion joints; full-scale testing; web breathing; postbuckling behaviour; fatigue; riveted connections;

   Sammanfattning : This thesis concerns three specific fatigue topics related to steel members in bridges, namely: (1) Modular Bridge Expansion Joints (MBEJs). Several premature fatigue failures of MBEJs have occurred in Europe and USA during the past decades. LÄS MER

5. 4. Mechanical braking systems for trains: A study of temperatures, fatigue and wear by experiments and simulations

   Författare :Mandeep Singh Walia; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; tread brakes; experiments; temperatures; disc brakes; wear; Railway braking; simulations; fatigue;

   Sammanfattning : Increased demand for shorter travel times, higher axle loads, increased volumes and increased punctuality of railway traffic calls for a better design and management of the railway subsystems. The present thesis deals with aspects of mechanical friction brakes, in the form of tread brakes and disc brakes. LÄS MER

7. 5. Simulation methods for hydropower flows : modeling and validation experiments

   Författare :T. Fredrik Engström; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Strömningslära; Fluid Mechanics;

   Sammanfattning : My research project aims for more accurate modeling of the flow in hydropower plants. By accurate modeling, it is possible to try different modifications on existing plants in an affordable manner. Also, entirely new designs can be tested before realization. Hydropower delivers almost 50% of Sweden's electricity demand with a production of 74 TWh. LÄS MER