Mechanical Engineering - Engineering Materials - Discussion

The correct answer is tuyers.

In a blast furnace, the charge (iron ore, coke, and limestone) is fed into the furnace through the top, but the tuyers are used to introduce air (or oxygen) into the furnace. The tuyers are pipes located around the circumference of the furnace, about halfway down its height, and are used to inject air into the furnace to support combustion and facilitate the smelting process.

Here's a brief overview of the other options:

- Stack: The stack is the vertical structure that surrounds the blast furnace and supports the furnace's height.
- Throat: The throat is the narrow section at the top of the furnace where the charge is fed in.
- Bosh: The bosh is the curved section of the furnace below the throat, where the charge begins to melt and react.

So, while the charge is fed into the furnace through the throat, the tuyers are used to introduce air into the furnace, making them the correct answer.

Open at upward side mouth.

Charge (lime, coal, maganse) provide upward side.

Good example, Thanks @Swapnil.

Throat is used to swell food from mouth to stomach.