väliskonvektsioonis

Väliskonvektsioon refers to heat transfer that occurs between a solid surface and a surrounding fluid that is in motion. This motion is driven by forces external to the fluid itself, such as pumps, fans, or the movement of the solid object through the fluid. Unlike natural convection, where fluid motion is caused by density differences due to temperature gradients, external convection relies on a mechanically induced flow.

The rate of heat transfer in external convection is dependent on several factors. These include the properties of the fluid, such as its thermal conductivity, viscosity, and density, as well as the velocity of the fluid flow. The geometry and orientation of the solid surface also play a significant role, as does the temperature difference between the surface and the fluid. A higher fluid velocity generally leads to a greater rate of heat transfer because it brings more of the cooler (or warmer) fluid into contact with the surface more rapidly, carrying away (or supplying) heat more effectively.

Common examples of external convection include forced air cooling of electronic components using a fan, the heat exchange that occurs when air flows over a car radiator, or the cooling of a hot object submerged in a moving stream of water. Understanding and calculating external convection is crucial in many engineering applications, from designing efficient heating and cooling systems to optimizing the thermal management of electronic devices.