Temperature Contours and Heat Transfer Characteristics

Fig.5: Temperature contours at Re=100, 500, 5000 and 10000, y=.25 m

Fig.6: Temperature contours at Re=100, 500, 5000 and 10000, y=.25 m, PTF

The above figures show the temperature contours of the computation domain of the plane channel for both the orientations of triangular prisms. The presence of the obstacle causes the formation of counter rotating vortices which cause the mixing of fluid and hence and increase in the heat transfer coefficient of the fluid and hence the temperature of the fluid increases. The rate of increment in temperature at outlet is more in 2^nd orientation as compare to 1^st.

Figure 7 and 8 shows the surface Nusselt number (Nu = h_xH/k) variation on the top and bottom wall of the channel with triangular prisms. Due to the effect of direction of flow with respect to the prism base, the variation of Nusselt number is more in the arrangement having prisms base parallel to the flow.

Fig.7: Variation of Nusselt number along the channel length in laminar flow zone

Fig.8: Variation of Nusselt number along the channel length in turbulent flow zone