Determination of the long-term performance of district heating pipes through accelerated ageing

We assess the feasibility of a collective district heating and cooling network based on a foundation pile heat exchanger in a new urban area in Vejle, Denmark. A thermogeological model for the area is developed based on geophysical investigations and borehole information. In tandem with a building energy demand model, the subsurface thermal properties serve as the input for a newly developed computational temperature model for collective heating and cooling with energy piles. The purpose of the model is to estimate the long-term performance and maximum liveable area that the energy piles are able to support. We consider two case studies where residential and office buildings dominate the building mass. We find that three to four floors can be supplied with heating and cooling from the energy piles, depending on the use and design of the buildings.

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WARMING ISSUES ASSOCIATED WITH THE LONG TERM SIMULATION OF HOUSING USING CFD ANALYSIS

Journal of Green Building ◽

10.3992/jgb.11.2.57.1 ◽

2016 ◽

Vol 11 (2) ◽

pp. 57-74 ◽

Cited By ~ 9

Author(s):

Aiman Albatayneh ◽

Dariusz Alterman ◽

Adrian W. Page ◽

Behdad Moghtaderi

Keyword(s):

Air Temperature ◽

Cfd Simulation ◽

Heating And Cooling ◽

And Performance ◽

External Volume ◽

Cooling Loads ◽

Long Term Performance ◽

Term Performance

The determination of internal building air temperature has an impact on the design and performance of a building in measuring thermal comfort and heating and cooling loads. There is software to assist with measuring internal building air temperature such as Autodesk CFD simulation. However, the use of Autodesk CFD simulation for the analysis appears to have an issue with simulations extending over a long term (i.e. months or years) as the internal air temperature in a building keeps rising with time. This paper addresses the challenges encountered using CFD simulation in the modelling of a building for long term performance. A new method to overcome the issue of the progressive rising of internal air temperature using two external air boundaries, one for the external volume (sky boundary) and the other surrounding the building, is suggested in the paper.

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Long term performance evaluation of cholestech reagent cassette lots for the determination of total cholesterol

Atherosclerosis ◽

10.1016/0021-9150(94)90165-1 ◽

1994 ◽

Vol 108 ◽

pp. S191

Author(s):

L Misner ◽

E.J. Rogers ◽

R.J. Nicolosi

Keyword(s):

Performance Evaluation ◽

Total Cholesterol ◽

Long Term Performance ◽

Term Performance

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Evaluation of Novel Assays in Clinical Chemistry: Quantification of Plasma Total Homocysteine

Clinical Chemistry ◽

10.1093/clinchem/46.8.1150 ◽

2000 ◽

Vol 46 (8) ◽

pp. 1150-1156 ◽

Cited By ~ 63

Author(s):

Ebba Nexo ◽

Frode Engbaek ◽

Per Magne Ueland ◽

Christina Westby ◽

Paudy O’Gorman ◽

...

Keyword(s):

Clinical Chemistry ◽

Systematic Evaluation ◽

Gas Chromatography Mass Spectrometry ◽

Immunological Methods ◽

Total Homocysteine ◽

Long Term Performance ◽

Term Performance ◽

Plasma Total Homocysteine

Abstract Background: There is a need for systematic evaluation of methods before their release to the market. We addressed this problem in novel homocysteine assays as part of an European Demonstration Project involving six centers in four countries. Methods: Two immunological methods for measurement of plasma total homocysteine (P-tHcy), the fluorescence polarization immunoassay (FPIA) and the enzyme immunoassay (EIA), were compared with two comparison methods, HPLC and gas chromatography–mass spectrometry (GC-MS). All laboratories performed the following procedures: (a) familiarization; (b) determination of linearity and precision by analyzing five plasma samples with interrelated concentrations for 20 days; (c) correlation using patients’ samples; and (d) assessment of long-term performance. Results: Both immunological methods were linear for P-tHcy between 5 and 45 μmol/L. The intralaboratory imprecision (CV) was <5% for FPIA and <9% for EIA used with a sample processor. The bias was −2% to 3% for FPIA and 2–4% for EIA used with a sample processor. Conclusions: The immunological methods provide results with little bias compared with HPLC and GC-MS. The imprecision of the assays must be considered in the context of their intended use(s).

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