Your email address will not be published. Save my name, email, and website in this browser for the next time I comment. It is one of the three modes of heat transfer, the others been conduction and radiation. There are two types of convection: Natural convection and Forced convection. Unlike conduction, convection requires macroscopic movement of matter.
As a result of this, convective heat transfer only occurs through liquid and gases. Boiling Water This is the most common and relatable household example of convection. For instance, When water is heated in a kettle, thermal expansion takes place. The process is repeated until the entire water in the kettle is heated up. In the daytime, the land surface is heated up making it warmer than a nearby sea. At night, the reverse is the case.
The air above the sea is warmer compared to that of the land. Why is land and sea breeze called natural convection? Air conditioner cools the room or containing structure through the same principle of convection. When turned on, it releases cool air. The human body continually produces warm air as well as on-going activities in the room.
As long as the air conditioner is turned on, this warm air will always be replaced by cool air. Body Blood Circulation. Although the heart is a single organ, it acts as a double pump. The second pump delivers the oxygen-rich blood to every part of your body.
The heart is the best example of forced convection in our body. Melting of Chilled Drink. This is because the temperature of the bottle surface increases as warm air blows over it. After a long time, it will be at the same temperature with the environment. Convection Oven Convection oven is quite different from the regular oven. But in a convection oven, the heat is evenly dispersed by fans inside the oven.
For baking purposes, the convection oven is preferred to the regular oven type because: the convective process set up in the oven thoroughly cooks the food accross all sides giving you an evenly cooked cake or mouth-watering steak. The process repeats again and again, and it all happens due to the temperature difference between the bottom and top of the kettle.
The movements of water molecules are convection currents. The heat sink is a passive heat exchanger that improves the rate of convective heat transfer. It is widely used in electronic equipment. Generally, a heat sink consists of a base and fins that extend outwards. Its performance is affected by various factors such as air velocity, fin design, and material used to build the heat sink.
Image credit: Freepik. The formation of land and sea breeze is one of the classic examples of convection. The Sun heats up both land and sea surface during the day.
But since the land has less heat-absorbing capacity than the sea, its surface temperature increases, heating up the air around it. The warm less dense air begins to rise, and low pressure is created. At the same time, a high-pressure area develops with cold, dense air over the top of the sea. Due to the difference in pressure, air flows from the sea to the land, and the cold air that comes along is called a sea breeze.
The process gets reversed during the night. The land cools down quicker than the sea, decreasing the air temperature around it and creating a high-pressure situation.
Now the cold air flows from the land to the sea, and this is what we call the land breeze. When air flows in and out of the buildings, flue gas stacks, or other similar structures, due to buoyancy, it is called the chimney effect. The high-density cold air always pushes the low-density hot gases up. The taller the structure and higher the thermal difference, the more the buoyancy force and thus the chimney effect. Many skyscrapers and cooling towers utilize the same principle to achieve natural ventilation and infiltration.
An industrial convection oven used in the airplane manufacturing industry. Convection ovens use convection mechanism to cook food faster than conventional ovens. They have fans to circulate hot air around the food, which enables food to cook more evenly at lower temperatures and in less time.
Industrial convection ovens are used for manufacturing many products, including non-food items. Convection plays a major role in the process of reducing ice thickness. The hotter the air and the faster it blows, the less time ice will take to melt. A Radiator transfers thermal energy from one medium to another. Despite the name, most radiators use convection instead of thermal radiation to transfer the bulk of their heat. They are mostly used in buildings, automobiles, and electronics. In a room heating system, for example, hot water or sometimes steam is generated in the internal coils.
As the water heats the coil, the air next to the radiator warms and raises. Once the heated air rises, cool air can be drawn into and through the radiator from underneath. This airflow generates vertical currents that distribute warm air throughout the room.
This occurs because hotter materials have less density than colder ones. In meteorology, convection is the transfer of heat and other atmospheric properties by the movement of masses of air, particularly in an upward direction. In geology, it is the slow movement of material below the Earth's crust. Some convection is manmade. There are numerous examples of convection in everyday life, including several common household occurrences.
Many weather conditions are the result of convection. From a meteorology perspective, convection is just an upward motion of air in the atmosphere. This sounds simple enough, but it can lead to severe weather in certain conditions.
While less commonly observed than everyday examples of convection that happen at home and weather phenomena, there are a number of other examples of convection associated with air movement. A number of natural phenomena are related to convection related to geology. A star has a convection zone where energy is moved by convection.
Outside the core is a radiation zone where plasma moves. A convection current forms when the plasma rises and the cooled plasma descends. These different examples of convection show how convection occurs throughout many human-made and natural occurrences.
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