Infant Incubator is used in hospitals to provide control environmental factors such as temperature, humidity, and oxygen concentration to the new brown babies. Lab Incubator is an same kind of machine which used to control environmental conditions, such as temperature,air and humidity, can be controlled, often used for growing bacterial cultures, hatching eggs artificially, or providing suitable conditions for a chemical or biological reaction.
Operating Principle.
The incubator uses diverse means of heat transference and environmental control to achieve conditions for specialized laboratory procedures. In general, these have a system of electrical resistors controlled by thermostats or microprocessors. As for the heat transference systems, the incubators use conduction and natural or forced convection.
Thermal conduction
In incubators functioning by thermal conduction, a set of electrical resistors transfers heat directly to the wall of the chamber where samples are incubated. The resistors constitute a region of high temperature, while the chamber is one of lower temperature. Transference of thermal energy always occurs from the region of higher temperature towards the region of lower temperature according to the following basic equation by Fourier:
Where:
q = quantity of heat transferred by conduction
k = thermal conductivity of the material
a = area of heat transference
∂T= temperature gradient in the direction of the heat flow
The minus sign (–) is introduced into the equation to fulfill the second law of thermodynamics.
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