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Convection caused by frontal or orographic lifting, or converging surface winds.
Wiki User
∙ 10y ago
Wiki User
∙ 10y agoWhen air is forced to ascend because it runs into a mountain, or when two jet streams of different speed or direction collide and the air is forced upwards.
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Which improves air circulation in forced air heating?
Convection
What type of Heat transfer is found in a hair dryer?
A hair dryer will use convection.
Describe the process of convection?
Convection is caused by temperature differences, in a gas such as air, which affect the gas density in local areas thus causing movement of the gas, generally upward due to buoyancy of warmer gas compared to the average density. Thus heat from a heating element near the floor of a room can be spread through the room without any forced circulation.
What causes convection in the atmosphere?
One Sentence Answer:In the generic meaning of the term, convection in fluids (liquid or gas) is the movement of the material (mass) of the fluid itself and it occurs because some force has been applied to the fluid to cause fluid flow.Deconstructing:Convection is mass transfer in a fluid and in its generic form is the same as fluid flow. The term convection is however the preferred term when describing the transport of heat by fluid flow. Even then, there is a distinction between "natural convection" and "forced convection."Heat transport by convection requires mass transport and refers to the movement of a warm region of fluid into a region of cold fluid or vice versa. Thermal energy is transported by the motion of the fluid. Another term would be "convective heat transport". The motion can be through natural convection or forced convection.Natural convection refers to convection that results from density variations in a fluid and hence buoyant forces acting to move less dense region up and more dense regions down. This is usually associated with differences in temperature in different regions of the fluid, but it can be caused by differences in physical or chemical make up of the fluid.Forced convection merely means that some artificial force, such as a fan, is acting to move the fluid to cause motion. Some would say this is not "true convection," and the term heat advection is then used to describe the force movement of heated fluids to transport thermal energy.Examples:1. Weather is largely driven by natural thermal convection. Air at the surface of the Earth is warmed by the Sun's energy and buoyant warm air rises because it has a lower density than cold air. The broad global circulation patterns of weather are however driven by forced convection with the driving force being the coriolis force that results from Earth's rotation.2. A convection oven, common in many households, is actually a forced convection oven and hat air is circulated by a fan.3. When a pot of water is placed over the burner or heating element of a stove, it is easy to observe the change from motionless water to a convecting fluid as the water at the bottom of the pot becomes warm and less dense and pushed upward by buoyant forces.4. Most houses which have central heating employ a fan to move the air. This is called forced air convection. (A century or more ago, most heated houses relied on natural convection to distribute warm air since electric fans were generally unavailable.)5. Lake turnover is a convection process where the water at the bottom of a lake is swapped with the water on top when the lake freezes or thaws. This occurs when the surface reaches 39 degrees Fahrenheit (4 degrees Celsius), the temperature when water density is maximum. In spring, ice melt and the water on top warms until 4 C, then sinks and in the process does the important tasks of bringing up nutrients and taking down oxygen. The mass transport and thermal transport are both important. (Smaller lakes constantly exchange water as a result of water currents created by wind at the surface which is forced convention and not natural thermal convection.)
How does heat travel through a fluid?
Heat convection occurs when bulk flow of a fluid (gas or liquid) carries heat along with the flow of matter in the fluid. The flow of fluid may be forced by external processes, or sometimes (in gravitational fields) by buoyancy forces caused when thermal energy expands the fluid (for example in a fire plume), thus influencing its own transfer. The latter process is sometimes called "natural convection". All convective processes also move heat partly by diffusion, as well. Another form of convection is forced convection. In this case the fluid is forced to flow by use of a pump, fan or other mechanical mean
What is the Difference in normal convection and forced convection?
Forced convection is forced [man-made] and normal convection is natural.
What are the applications of forced convection?
Forced convection are used in car radiators, cooling towers, air cooled heat exchangers etc.
Convection always occurs in what two forms?
forced and natural convection possibly
What provides forced convection?
velocity of fluid..
Are heat vents examples of forced or natural convection?
Natural
A forced air heater heats a house through?
convection
is the forced convection is the movement of hot air by a fan?
True
Which improves air circulation in forced air heating?
Convection
In a forced - air heating system the warm air circulates by convection?
No, its forced by an electric blower...otherwise it wouldn't be forced air
What are applications of convection?
Forced convection are used in car radiators, cooling towers, air cooled heat exchangers etc.
What are the applications of convection?
Forced convection are used in car radiators, cooling towers, air cooled heat exchangers etc.
What does free and forced convection mean?
Forced convection is when air ascends as a result of another force, such as the actions of fronts, orographic lifting, or converging wind. Free convection is caused by a factor such as intense heating of the Earth's surface, which warms air and causes it to rise.
