Confined buoyant plume

Underlying Flow Regime 4-09 © copyright ERCOFTAC 2004

References

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List of Figures

Figure 3. Theoretical curves for 2D line-source plumes for a) interface height and (b) reduced gravity (equations 5 & 7). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 4. Theoretical curves for 3D point-source plumes for a) interface height and (b) reduced gravity (equations 8 & 10). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 8. The geometry of the room considered in the CFD simulations. In the 3D simulations the breadth of the room was 1.0m in the direction normal to the page. (Note the difference of notation from that used elsewhere in the paper; here a_t = a_u and a_b = a_l). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 9. CFD model domain for 2D line-source plumes showing location and type of boundaries (Cook & Lomas 1998). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 10. CFD model domain for 3D point-source plumes showing a) location and type of boundaries b) computational mesh (Cook & Lomas 1997). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 11. Calculated flow fields (temperature contours and velocity vectors) for 2D line-source plume simulations for (a) plume source heat input, Q = 200 W, effective vent size =0.148, 'standard' k–ε turbulence model; (b) Q = 1000 W, =0.148, 'standard' k-ε turbulence model; (c) Q = 200 W, = 0.148, RNG k–ε turbulence model; (d) Q = 1000 W, = 0.148, RNG k–ε turbulence model; (e) Q = 200 W, = 0.075, RNG k–ε turbulence model; (f) Q = 200 W, =0.227, RNG k–ε turbulence model. Note that only half the room width is shown; the plume and symmetry plane are on the right-hand side of the region shown. (Cook & Lomas 1998) Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 12. Calculated flow fields (temperature contours and velocity vectors) for 3D point-source plume simulations (Cook & Lomas 1997) for (a) plume source heat input, Q = 200 W, effective vent area =0.0304, 'standard' k-ε turbulence model; (b) Q = 200 W, =0.0304, RNG k–ε turbulence model; (c) Q = 200 W, RNG k–ε turbulence model, plane normal to room major-axis plane 0.2m from the wall; (d) Q = 1000 W, =0.0304, RNG k–ε turbulence model. Note that in a), b) and d), only half the room width is shown; the plume and symmetry plane are on the right-hand side of the region shown. (Cook & Lomas 1998) Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 13. Measurements of a) interface height and b) reduced gravity for 2D line-source plumes, compared with the theoretical model and salt-bath experiments of Linden et al. (1990). In the theoretical curves the value of entrainment coefficient used is α = 0.1 has been used. Note that no-virtual origin corrections have been made and C_t= C_b= 1.0.) Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Figure 14. Measurements of interface height for 3D point-source plumes, compared with the theoretical model and salt-bath experiments of Linden et al. (1990). Theoretical curves for two different values of entrainment coefficient are shown: the typical value of α = 0.1 and the value inferred from the CFD measurements of α = 0.14. Note that no-virtual origin corrections have been made and C_t= C_b= 1.0. (From Cook 1998). Originals of all the figures in this UFR are in UFR4-09_Figures.pdf

Contributors: Jake Hacker - Arup