Sökning: "heat capacity"

Visar resultat 6 - 10 av 298 avhandlingar innehållade orden heat capacity.

1. 6. Non-Azeotropic Mixtures as Working Fluids in Heat Pumps: A theoretical and experimental study

   Författare :Marine Högberg; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; HCFC123; HCFC124a; HCFC22; performance comparison; COP; non-azeotropic mixture; capacity; sensitivity analysis; HFC152a; heat pump; CFC114; ethyl chloride; experimental study; HCFC142b; two-stage cycle;

   Sammanfattning : Due to the fact that CFC (Chloro-Fluoro-Carbon) fluids will be forbidden as working fluids in heat pumps for environmental reasons, there is an urgent need for alternatives. As one alternative type of fluid, non-azeotropic mixtures have been suggested. This thesis deals with such mixtures. LÄS MER

3. 7. Capacity-controlled Ground Source Heat Pump Systems for Swedish single-family dwellings

   Författare :Hatef Madani; Per Lundqvist; Joachim Claesson; Jose Miguel Corberan Salvador; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Heat Pump; Capacity control; ground; ground source; geothermal;

   Sammanfattning : The overall objective of this thesis is to develop a structured method to approach the challenge of better understanding the techniques and potential for capacity control in Ground Source Heat Pump (GSHP) systems used in Swedish single-family dwellings. This thesis aims at development of a generic model of the system that can be used for comparative, descriptive, and predictive analysis of capacity controlled GSHP systems in single-family dwellings. LÄS MER

4. 8. Experimentella studier av värmeflöden och värmelagring i ett bebott flerbostadshus

   Författare :Lars Stenlund; Gunnar Bäckström; Olov Sandberg; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Energy balance; heat storage; heat flow; night setback; buildings; time constants;

   Sammanfattning : The study is experimentally inclined, with a high target precision for performance measurement. A comprehensive programme of measurements was carried out in a two-storey building, having a massive structure and dating from 1970. Measurements were made continuously during the heating season from a total of about 70 points. LÄS MER

5. 9. Experimental Investigation of Refrigerant Charge Minimisation of a Small Capacity Heat Pump

   Författare :W. Primal D. Fernando; Björn Palm; Alberto Gavallini; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; heat pump; propane; low-charge; Wilson plot method; minichannels; aluminium heat exhangers; single.phase flow; Mechanical and thermal engineering; Mekanisk och termisk energiteknik;

   Sammanfattning : Enormous quantities of heat are available in air, soil, water, exhaust air from buildings, and in waste water of any kind. However these heat sources are use-less for heating purposes since their temperatures are lower than the tempera-ture required for heating. LÄS MER

7. 10. Sustainable building ventilation solutions with heat recovery from waste heat

   Författare :Behrouz Nourozi; Sture Holmberg; Adnan Ploskic; Qian Wang; Shia-Hui Peng; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wastewater heat recovery; balanced mechanical ventilation; defrosting reduction; heat recovery efficiency; thermal load shifting; renewables; Byggvetenskap; Civil and Architectural Engineering;

   Sammanfattning : The energy used by building sector accounts for approximately 40% of the total energy usage. In residential buildings, 30-60% of this energy is used for space heating which is mainly wasted by transmission heat losses. A share of 20-30% is lost by the discarded residential wastewater and the rest is devoted to ventilation heat loss. LÄS MER