Sökning: "constant load"

Visar resultat 1 - 5 av 188 avhandlingar innehållade orden constant load.

1. 1. Dynamic Load Models for Power Systems - Estimation of Time-Varying Parameters During Normal Operation

   Författare :Ines Romero; Industriell elektroteknik och automation; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; voltage stability; Load modeling; modeling and identification; dynamic load models; normalization in reactive load models;

   Sammanfattning : Economic and environmental concerns will slow down the expansion of the transmission system in many countries. The addition of new transmission lines will be few and far between. The de-regulation of the power supply will introduce new power flow patterns on the bulk transmission systems. LÄS MER

3. 2. Fatigue crack growth experiments and analyses - from small scale to large scale yielding at constant and variable amplitude loading

   Författare :Pär Ljustell; Fred L. Nilsson; Bo Alfredsson; Gunnar Härkegård; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fracture mechanics; fatigue crack growth; finite elements analysis; small scale yielding SSY ; large scale yielding LSY ; low cycle fatigue LCF ; crack tip opening displacement CTOD ; crack closure; potential drop method; constant amplitude load; variable amplitude load; inconel 718; stainless steel 316L;

   Sammanfattning : This thesis is on fatigue crack growth experiments and assessments of fatigue crack growth rates. Both constant and variable amplitude loads in two different materials are considered; a nickel based super-alloy Inconel 718 and a stainless steel 316L. LÄS MER

4. 3. Three-Dimensional Load-Deformation Relationships of Arbitrarily Loaded Coiled Springs

   Författare :Lars Lindkvist; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; extended stiffness model; helical spring; non-linear deformation; stiffness matrix; coiled spring; arbitrary load; large deformation; three-dimensional;

   Sammanfattning : This paper reports the development of a computer based tool that can be used to predict the three-dimensional load-deformation relationships of arbitrarily loaded coiled springs. The non-linear deformation of the spring is calculated by dividing the spring into small elements for which the load-deformation relationships can be considered to be linear. LÄS MER

5. 4. Corrosion testing of heat exchanger tubing

   Författare :Ulf Kivisäkk; KTH; []
   Nyckelord :corrosion testing; heat exchanger; stainless steels; general corrosion; immersion testing; activation; stress corrosion cracking; constant load; u-bends; relaxation; dewpoint corrosion;

   Sammanfattning : Heat exchanger tubes are commonly made from stainless steel.In a heat exchanger both the process fluid and the cooling orheating media can be corrosive. It is therefore important to beable to select materials that do not suffer from corrosion.Current methods in this area, however, suffer from limitationsand shortcomings. LÄS MER

7. 5. Thermal Cycling, Creep- and Tensile Testing of Cast Exhaust Materials at Elevated Temperatures

   Författare :Christian Öberg; Stefan Jonsson; Henrik Östling; KTH; []
   Nyckelord :creep; constant-load; thermal cycling; tensile test; cast materials; cast iron; exhaust materials.; Teknisk materialvetenskap; Materials Science and Engineering;

   Sammanfattning : An exhaust manifold of a truck engine is subjected to tough conditions. As the truck is started, operated and shut down, it becomes subjected to thermal cycling up to around 800°C. At such high temperatures, corrosion, fatigue and creep are active degradation mechanisms. LÄS MER