Utnyttelse av solenergi i betong - Høgskolen i Narvik

Innholdsfortegnelse
Utnyttelse av solenergi i betong
Forord ............................................................................................. 2
1. Innledning .................................................................................... 5
1.1 Bakgrunn ....................................................................................................................................... 5
1.2 Formål ............................................................................................................................................ 5
1.3 Avgrensninger ................................................................................................................................ 5
2. Teori ........................................................................................... 6
2.1 Varmelære ..................................................................................................................................... 6
2.1.1 Varmetransport ...................................................................................................................... 6
2.1.2 Emissivitet ............................................................................................................................ 10
2.1.3 Absorpsjon, refleksjon og transmisjon ................................................................................. 10
2.1.4 Kirchhoff’s lov ....................................................................................................................... 11
2.1.5 Termisk diffusivitet ............................................................................................................... 11
2.1.6 Termisk masse ...................................................................................................................... 11
2.2 Solenergi ...................................................................................................................................... 12
2.2.1 Solstråling ............................................................................................................................. 12
2.2.2 Solvarme ............................................................................................................................... 13
3. Eksperiment ............................................................................... 16
3.1 Innledning .................................................................................................................................... 16
3.2 Materialegenskaper .................................................................................................................... 16
3.2.1 Trykkfasthet .......................................................................................................................... 16
3.2.2 Måling av spektral absorpsjon.............................................................................................. 16
3.2.3 Måling av termisk emissivitet ............................................................................................... 20
3.3 Forsøk .......................................................................................................................................... 22
3.3.1 Utstøping av betongprøver .................................................................................................. 22
3.3.2 Måling av absorpsjon av solenergi ....................................................................................... 27
5. Diskusjon………………………………...................................................37
4. Konklusjon………………………………………………………………………..……..38
6. Referanser…………………………………………………………………….….……..39
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