Sökning: "heat convection"

Visar resultat 6 - 10 av 109 avhandlingar innehållade orden heat convection.

1. 6. Heat and Mass Transfer in Built Structures - Numerical Analyses

   Författare :Jinkai Wang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; air convection; heat; numerical procedure; air and moisture transport; long-term thermal performance; numerical stability; gas-filled foam; thermal aging; simulation;

   Sammanfattning : Heat and mass transport processes are often present simultaneously in built structures in building applications. The emphasis of this thesis is to contribute to knowledge about predicting the effects of combined heat and mass transport in built structures. LÄS MER

3. 7. Preheating of ambient air by a system of earth tubes as a heat source for buildings

   Författare :Carl-Eric Nilsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; earth tubes; preheating of air; corrugated plastic pipes; natural heating; heat extraction by air; fictitious temperature; earth heating; thermal pulses; earth heat exchanger; Heat convection coefficient; heat tubes;

   Sammanfattning : .... LÄS MER

4. 8. On optimization of natural convection flows

   Författare :Clio Saglietti; Dan S. Henningson; Kurt Maute; KTH; []
   Nyckelord :Natural convection cooling; topology optimization; flow optimization; heat sink; conjugate heat transfer; differentially heated cavity; optimal initial disturbances; adjoint optimization;

   Sammanfattning : Two different techniques are presented for enhancing the thermal  performance of natural convection cooled heat sinks. The physics is  described by solving the conjugate heat transfer problem with a  spectral element method. The temperature distribution is computed in  two sub-domains, whose solution is then conjugated. LÄS MER

5. 9. Exhaust Heat Utilisation and Losses in Internal Combustion Engines with Focus on the Gas Exchange System

   Författare :Habib Aghaali; Hans-Erik Ångström; Carlos Guardiola; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbocharger; heat transfer; heat loss; exhaust heat utilisation; waste heat recovery; turbocompound; divided exhaust period; internal combustion engine; gas exchange; pumping loss; variable valve timing; WHR; DEP; Turbo; värmeöverföring; värmeförluster; avgasvärme utnyttjande; förluster vid värmeåtervinning; turbocompound; delad avgasperiod; förbränningsmotor; gasväxling; pumpningsförlust; variabla ventiltider; WHR; DEP; Vehicle and Maritime Engineering; Farkostteknik; Energy Technology; Energiteknik;

   Sammanfattning : Exhaust gas energy recovery should be considered in improving fuel economy of internal combustion engines. A large portion of fuel energy is wasted through the exhaust of internal combustion engines. Turbocharger and turbocompound can, however, recover part of this wasted heat. LÄS MER

7. 10. Natural Convection Heat Transfer in a Horizontal Thermal Insulation Layer Underlying an Air Layer

   Författare :Mihail Serkitjis; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; air layer; thermal insulation; composite system; heat transfer; numerical simulation; natural convection; porous layer; measurements; testing equipment;

   Sammanfattning : In the thesis a study is made of the influence of natural convection on heat transfer in a composite system comprising a porous material heated from below and an air space situated above this. The measuring apparatus, a Wind Box which has been designed and developed at the Department of Building Physics is described. LÄS MER