SwePub
Sök i LIBRIS databas

  Utökad sökning

WFRF:(Gehlin Signhild)
 

Sökning: WFRF:(Gehlin Signhild) > Influence of natura...

Influence of natural convection in water-filled boreholes for GCHP

Gustafsson, Anna-Maria (författare)
Luleå tekniska universitet,Arkitektur och vatten
Gehlin, Signhild (författare)
Swedish Society of HVAC Engineers, Stockholm
 (creator_code:org_t)
2008
2008
Engelska.
Ingår i: ASHRAE Transactions. - 0001-2505. ; 114:1, s. 416-423
  • Tidskriftsartikel (refereegranskat)
Abstract Ämnesord
Stäng  
  • In groundwater filled borehole heat exchangers (BHE), convective flow inside the borehole water will affect the heat transfer. Since the convective flow is dependent of the temperature gradient, different injection rates and ground temperatures will result in different borehole thermal resistance. This paper describes the influence of natural convection in water-filled boreholes in impermeable bedrock for ground-coupled heat pump (GCHP) systems. An overview of groundwater-filled boreholes and the influence of groundwater movements are presented followed by numerical simulations and field measurements to further investigate the influence. The results from the simulations of the three-dimensional, steady-state model of a 9.8 ft (3 m) deep BHE are compared to evaluated results from performed thermal response test (TRT). The results show that convective flow in groundwater-filled BHE results in 5-9 times more efficient heat transfer compared to stagnant water when heat carrier temperatures are in the range of 50-86°F (10-30°C). The size of the convective flow depends on the temperature gradients in the borehole. This shows the importance of on-site investigation of thermal properties using appropriate power injection rates similar to those in the system to be built. This research is part of an on-going project to find ways to estimate the heat transfer including convective flow and to incorporate the findings into the design of GCHP systems. TRT are today a common way to determine heat transfer properties for a BHE and its surroundings. Performing TRT measurements with several injection rates is a way to evaluate the dynamic thermal response including the change in convective flow due to changes in temperature levels. If this dynamic response would be included in design tools a more thorough design of the BHE system is performed. Here, the early result of this research is presented

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Samhällsbyggnadsteknik -- Vattenteknik (hsv//swe)
ENGINEERING AND TECHNOLOGY  -- Civil Engineering -- Water Engineering (hsv//eng)

Nyckelord

Vattenteknik
Water Resources Engineering
VA-teknik
Urban Water Engineering

Publikations- och innehållstyp

ref (ämneskategori)
art (ämneskategori)

Hitta via bibliotek

Till lärosätets databas

Hitta mer i SwePub

Av författaren/redakt...
Gustafsson, Anna ...
Gehlin, Signhild
Om ämnet
TEKNIK OCH TEKNOLOGIER
TEKNIK OCH TEKNO ...
och Samhällsbyggnads ...
och Vattenteknik
Artiklar i publikationen
ASHRAE Transacti ...
Av lärosätet
Luleå tekniska universitet

Sök utanför SwePub

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Stäng

Kopiera och spara länken för att återkomma till aktuell vy