formules.py

Created on April 02, 2025
735 Bytes
Conduction:
Tmat1=(T0-T1)/l1  z + T0
Tmat2=(T2-T0)/l2 z + T0

K1S(T1-T0)/l1=K2S(T0-T2)/l2

Pth=(KS ΔT)/l
R=l/(KS)
Pth=(ΔT*S)/R
Pth=hc*S*ΔT

Req= R1+R2 
eT/(landaT*S)= e1/(landa1*S1) + e2/(landa2*S2)

En//: Rth 1//2: (Rth1*Rth2)/(Rth1+Rth2)


Convection:
Re=(u*D)/v 
avec u (vitesse)
D(distance ecoulement)
v (viscosite cinematique)

Ra=(B*g*ΔT*L^3)/v*alpha

avec B=1/T
alpha= landa/(ro*Cp)
v=μ/ro
L (distance)

Nu=(C*Ra)^n = (hL)/landa

P=h*ΔT*S


Conduction/convection:
U=1/R
R=e/landa

Rth= 1/hi + (e/landa+e/landa...)+ 1/he

P=S*ΔT/Rth= U*S*ΔT
J=Pth/S

Utot= 70% S1*U1 + 30%S2*U2

E=P*Δt= flux*S*Δt 
E=(ΔT*Δt)/Rth
E=U*ΔT*Δt


M(emittance)= cste stefan *T^4
landa max * T = 2898 μm.K Wien
M landa max = B*T^5 Wien2