Page 298 - Thermal Hydraulics Aspects of Liquid Metal Cooled Nuclear Reactors

268 Thermal Hydraulics Aspects of Liquid Metal Cooled Nuclear Reactors

1.2

1
¯ q +

0.8
+
¯ q
q + 0.6 t

0.4

0.2
+
¯ q M
0
0 500 1000 1500 2000
y +

Fig. 6.1.2.11 Heat flux decomposition for the turbulent channel flow at Pr ¼ 0.025 and Re τ ¼
0 +
1
+
+
+
+
0
2000. Molecular heat flux q ¼ Pr dθ =dy , turbulent heat flux q ¼ v θ , and total heat
M
t
+
+
+
flux q ¼ q + q .
M t
(From Duponcheel, M., Bricteux, L., Manconi, M., Winckelmans, G., Bartosiewicz, Y., 2014.
Assessment of RANS and improved near-wall modeling for forced convection at low Prandtl
numbers based on LES up to Re τ ¼ 2000. Int. J. Heat Mass Transf. 75 (2), 470–482.)
4
3.5
3
2.5
α t
α 2
1.5
1
0.5

0
0 500 1000 1500 2000
y +

Fig. 6.1.2.12 Turbulent heat diffusivity for the turbulent channel flow at Re τ ¼ 2000: LES Pr ¼
0.01 (solid), LES Pr ¼ 0.025 (dash).
(From Duponcheel, M., Bricteux, L., Manconi, M., Winckelmans, G., Bartosiewicz, Y., 2014.
Assessment of RANS and improved near-wall modeling for forced convection at low Prandtl
numbers based on LES up to Re τ ¼ 2000. Int. J. Heat Mass Transf. 75 (2), 470–482.)