Optically Thin Fibrous Insulations

Fricke, J.; Caps, R.; Hümmer, E.; Doll, Gary L.; Arduini, Mariacarla; Ponte, F De

doi:10.1520/stp23331s

Cited by 7 publications

(2 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results, obtained from Equations (8) and (9), show a strong increase of k'hLO with rising X,, confirming qualitatively the observed coupling of radia- FIGURE 8. Extracted effective emissivities, ef , as a function of foil number, N, at an insulation thickness of d = 1 mm and a temperature of 300 K, same symbols used as m Figure 7, the drawn lines are a guide to the eye.…”

Section: Influence Of Spacer Materialssupporting

confidence: 75%

See 1 more Smart Citation

Investigation of Heat Transfer in Evacuated Foil-Spacer Multilayer Insulations

Degen

Rossetto

Reichenauer

et al. 1992

Journal of Thermal Insulation and Building Envelopes

View full text Add to dashboard Cite

For a comparison of different evacuated foil-spacer insulations, the heat transfer coefficient, as a function of temperature and packing density, was measured using an evacuable, guarded flat-plate apparatus. The mean temperature was varied between 260 K and 550 K, the packing density from 1 to 15 foils per mm. Other experimentally changed parameters were type and emissivity ∈ f of foils and type of spacer. The measurements allow one to determine contributions from solid conduction and radiative transport, as well as the coupling between these two heat transfer modes. The coupling is characterized by an effective foil emissivity ∈ * f , with ∈ f ≤ ∈ * f ≤ 1. The goal of the investigation is the optimization of foil-spacer vacuum super-insulations. The lowest heat transfer coefficients achieved were 0.01 W.m -2. K -1 at 300 K for a 1 mm thick stack of 7 polyimide foils, aluminized on both sides with glass fiber fabric spacers.

show abstract

Section: Influence Of Spacer Materialssupporting

confidence: 75%

“…For a homogeneous medium the resulting total heat flux k3f1ux was calculated using a three-flux approximation. As shown in Reference [9], k3f1ux can be expressed as a function of Tr, the solid conductivity X, = ks~d, the boundary emissivity E, as well as the scaled optical thickness 7: and albedo úJt:…”

Section: Heat Transfer In Evacuated Foil-spacer Stacksmentioning

confidence: 99%