Convection works by transferring heat from a hot substance to a cooler one through the motion of one of the substances. For example, as wind passes over a hot substance, heat from the substance transfers to the air particles, cooling the hot substance and slightly warming the air.Know More
Convection is effective because the continuous flow of the cooler substance allows for continued heat transfer. Because the movement is so important for convection, consideration of convection currents, which describe the patterns of movement of the substances, helps provide a detailed description of the effect.
Two broad types of convection exist: spontaneous convection and forced convection. Spontaneous convection occurs when the convection currents arise naturally. For example, winds moving from cooler to warmer areas naturally cool the surfaces they pass over. Ocean currents are another form of spontaneous convection; the flow of water in the ocean leads to heat transfer for different land masses, and it cools water emerging from deep ocean heat vents.
Forced convection occurs when the cooling substance is propelled along the surface of the hotter substance or vice versa. For example, during beer brewing, many breweries force large quantities of cold water through copper pipes that make contact with boiling wort; this leads to rapid temperature drops in the wort, speeding the brewing process.Learn more about Motion & Mechanics
Actuators depend on transfer of energy – via electricity, hydraulic pressure, human muscle or otherwise – to perform mechanical work that sets a system in motion or controls it. Actuators can be mechanical systems, such as a pneumatic pump, or digital, such as laser printer drivers.Full Answer >
Hydraulic power works by applying force at one point to transfer it to another point using an incompressible fluid. The incompressible fluid is usually an oil of some kind.Full Answer >
A hydraulic arm works by using high fluid pressure, created by a pump, to force a piston in a cylinder to move. As a valve is opened one way, the fluid is allowed to enter the cylinder and force the piston to move.Full Answer >
A mechanical seal works by creating a running seal between the revolving and stationary components of a pump shaft. Unlike a compression packing gland, this device effectively minimizes leakage problems.Full Answer >