Question

physical princple workin of chimneys of lamp and furnances​

Answer 1

Answer:

Here are some simple scientific fundamentals to explain how and why a chimney works. This page should make it easier to understand how a CSIA Certified Chimney Sweep® can diagnose smoking or odor problems with your chimney.

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Your House as a System

Even though you can't see it, the air in your house is in constant motion. In general, airflow tries to flow out of your house in the upper parts and replacement air tries to flow into your house in the lower parts of your house. Thinking of your house as a system makes it easy to understand the reasons for that airflow. Many changing factors, including: stack effect, wind loading, interior mechanical systems, and fuel-burning appliances such as furnaces, fireplaces, wood stoves and water heaters influence a home's airflow.  

Homes built or renovated in the past 25 years are more airtight than older homes. This makes it much more difficult for replacement air to enter the home. As the saying goes, “hot air rises”, and so does the warm air in your home.  

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Increasing the draft in your chimney is like opening the faucet wider on the hose. The simplest way to increase the draft in your chimney is to burn the fire hotter - hotter air is lighter, so it has more pull. Another way to get more draft is to increase the height of your chimney - except when the chimney is already so tall that frictional forces negate the effect of the extra height. ​ Given the same amount of pressure, a larger pipe can carry a greater volume of water than a smaller one. The same is true for chimneys - with the same amount of draft (pressure) a larger flue will exhaust more smoke from your fireplace than a smaller one. Similar to how a water hose can be kinked or plugged, the airflow in your chimney can have a restriction that slows down the smoke flowing up the chimney.

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Explanation: