Repeat Prob. 15–35, except create a three-dimensional room, with an air supply and an air return in the ceiling. Compare the two-dimensional results of Prob. 15–35 with the more realistic three-dimensional results of this problem. Discuss.

Data from Problem 15-35

Choose one of the room geometries of Probs. 15–32 and 15–34, and add the energy equation to the calculations. In particular, model a room with air-conditioning, by specifying the supply air as cool (T = 18°C), while the walls, floor, and ceiling are warm (T = 26°C). Adjust the supply air speed until the average temperature in the room is as close as possible to 22°C. How much ventilation (in terms of number of room air volume changes per hour) is required to cool this room to an average temperature of 22°C? Discuss.

Data from Problem 15-34

Repeat Prob. 15–32, except move the supply and/or return vents to various locations in the ceiling. Compare and discuss.

Data from Problem 15–32

Generate a computational domain to study ventilation in a room (Fig. P15–32). Specifically, generate a rectangular room with a velocity inlet in the ceiling to model the supply air, and a pressure outlet in the ceiling to model the return air. You may make a two-dimensional approximation for simplicity (the room is infinitely long in the direction normal to the page in Fig. P15–32). Use a structured rectangular grid. Plot streamlines and velocity vectors. Discuss.

FIGURE P15–32

Air supply Air return