Question

Some chimney pipes have a T-shape, with a crosspiece on top that helps draw up gases whenever there is even a slight breeze. Explain how this works in terms of Bernoulli’s principle.

a) Increased cross-sectional area increases velocity
b) Gases are drawn due to decreased pressure
c) Bernoulli's principle is not applicable to chimneys
d) Breeze has no effect on chimney gases

Answer 1

T-shaped chimney pipes use Bernoulli's principle by causing a breeze to increase the velocity of air over the chimney, thus decreasing the air pressure above the chimney and helping to draw up gases inside.

Step-by-step explanation:

The T-shaped chimney pipes utilize Bernoulli's principle to enhance the draft, which is the force that pulls air and gases up the chimney. This principle states that in a fluid flow, there is an inverse relation between pressure and velocity - when velocity increases, pressure decreases. When a breeze blows over the crosspiece of a T-shaped chimney, it increases the velocity of air passing over the chimney tip, which according to Bernoulli's principle, decreases the air pressure just above the chimney pipe. The higher pressure inside the chimney, relative to the decreased outside pressure, pushes the gases up and out. This is a sophisticated application of fluid dynamics, and it ensures chimneys vent out the smoke and gases efficiently, especially in the presence of a breeze.