Search results
Results From The WOW.Com Content Network
Thermal conduction (power) is the heat per unit time transferred some distance ℓ between the two temperatures. κ is the thermal conductivity of the material. A is the cross-sectional area of the object. ΔT is the difference in temperature from one side to the other. ℓ is the length of the path the heat has to be transferred.
Thermal equation of state of solids. In physics, the thermal equation of state is a mathematical expression of pressure P, temperature T, and, volume V. The thermal equation of state for ideal gases is the ideal gas law, expressed as PV=nRT (where R is the gas constant and n the amount of substance), while the thermal equation of state for ...
Kinetic theory of gases. The temperature of the ideal gas is proportional to the average kinetic energy of its particles. The size of helium atoms relative to their spacing is shown to scale under 1,950 atmospheres of pressure. The atoms have an average speed relative to their size slowed down here two trillion fold from that at room temperature.
There are some notable similarities in equations for momentum, energy, and mass transfer [7] which can all be transported by diffusion, as illustrated by the following examples: Mass: the spreading and dissipation of odors in air is an example of mass diffusion. Energy: the conduction of heat in a solid material is an example of heat diffusion.
A hot, less-dense lower boundary layer sends plumes of hot material upwards, and cold material from the top moves downwards. Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy (heat) between physical systems. Heat transfer is classified into various mechanisms, such ...
The macroscopic energy equation for infinitesimal volume used in heat transfer analysis is [6] = +, ˙, where q is heat flux vector, −ρc p (∂T/∂t) is temporal change of internal energy (ρ is density, c p is specific heat capacity at constant pressure, T is temperature and t is time), and ˙ is the energy conversion to and from thermal ...
v. t. e. The first law of thermodynamics is a formulation of the law of conservation of energy in the context of thermodynamic processes. The law distinguishes two principal forms of energy transfer, heat and thermodynamic work, that modify a thermodynamic system containing a constant amount of matter. The law also defines the internal energy ...
Sublimation is the transition of a substance directly from the solid to the gas state, without passing through the liquid state. [1] The verb form of sublimation is sublime, or less preferably, sublimate. [2] Sublimate also refers to the product obtained by sublimation. [2][3] The point at which sublimation occurs rapidly (for further details ...