60 research outputs found
A Novel Role of Three Dimensional Graphene Foam to Prevent Heater Failure during Boiling
We report a novel boiling heat transfer (NBHT) in reduced graphene oxide (RGO) suspended in water (RGO colloid) near critical heat flux (CHF), which is traditionally the dangerous limitation of nucleate boiling heat transfer because of heater failure. When the heat flux reaches the maximum value (CHF) in RGO colloid pool boiling, the wall temperature increases gradually and slowly with an almost constant heat flux, contrary to the rapid wall temperature increase found during water pool boiling. The gained time by NBHT would provide the safer margin of the heat transfer and the amazing impact on the thermal system as the first report of graphene application. In addition, the CHF and boiling heat transfer performance also increase. This novel boiling phenomenon can effectively prevent heater failure because of the role played by the self-assembled three-dimensional foam-like graphene network (SFG).open2
Heat Transfer in a Cavity Packed with Fibrous Glass
Nomenclature c p = specific heat at constant pressure H = height of cavity H/W = aspect ratio K = permeability Nu* = modified Nusselt number, X e ff/Xn Ra* = modified Rayleigh number, gllf (T h -T v )WK/a*vf T = temperature W = width of cavity or distance between hot and cold walls a* = thermal diffusion, X 0 /(pe p )/ li = thermal expansion coefficient A e rr = effective thermal conductivity, X r( , + U + Ku Xra = thermal conductivity due to radiation \ c d = thermal conductivity of fibrous glass ,\." -thermal conductivity due to convection \o = thermal conductivity of fibrous glass layer without convection, X", + K-d -/ = specific weight of fibrous glass v = kinematic viscosity p = density Subscripts c = cold wall / = fluid (air) /i = hot wall 0 = without convectio
- …