We consider $Si_c Ge_{1-c}$ graded systems of length $L=3mm$ and $L=100nm$, under the action of an electric field $mathbf E$, and crossed by an electrical current $mathbf i$, the two sides of which are kept at two different temperatures $T_h$ and $T_c$. The dependence on composition and temperature of the thermal conductivity is analyzed. We evaluate the thermal conductivity in correspondence of the constant temperatures $T=300K,,T=400K,,T=500K$, and investigate the thermoelectric efficiency of the system as function of the stoichiometric variable $c$ and of the effective temperature gradient $rac{T_h-T_c}{L}$. For each temperature, we calculate the values of $c$ in the interval $[0,1]$ which realize the optimal efficiency of the thermoelectric energy conversion. The corresponding values of the thermal conductivity are determined as well. For $L=3mm$, we find that the best efficiency of thermoelectric energy conversion is achieved at $T=500K$, $c=0.325568$, and $lambda=7.3444,, Wm^{-1}K^{-1}$. For $L=100nm$, we obtain the best efficiency at $T=500K$, $c=0.613937$, and $lambda=0,1510,, Wm^{-1}K^{-1}$.
Thermoelectric efficiency of graded S ic Ge1-c alloys.
P. Rogolino;
2018-01-01
Abstract
We consider $Si_c Ge_{1-c}$ graded systems of length $L=3mm$ and $L=100nm$, under the action of an electric field $mathbf E$, and crossed by an electrical current $mathbf i$, the two sides of which are kept at two different temperatures $T_h$ and $T_c$. The dependence on composition and temperature of the thermal conductivity is analyzed. We evaluate the thermal conductivity in correspondence of the constant temperatures $T=300K,,T=400K,,T=500K$, and investigate the thermoelectric efficiency of the system as function of the stoichiometric variable $c$ and of the effective temperature gradient $rac{T_h-T_c}{L}$. For each temperature, we calculate the values of $c$ in the interval $[0,1]$ which realize the optimal efficiency of the thermoelectric energy conversion. The corresponding values of the thermal conductivity are determined as well. For $L=3mm$, we find that the best efficiency of thermoelectric energy conversion is achieved at $T=500K$, $c=0.325568$, and $lambda=7.3444,, Wm^{-1}K^{-1}$. For $L=100nm$, we obtain the best efficiency at $T=500K$, $c=0.613937$, and $lambda=0,1510,, Wm^{-1}K^{-1}$.Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
