Calorimeter to determine the specific heat capacities of liquids
Calorimetry deals with the measurement of heat energy.These measurements are based on temperature changes, which are used to determine the amount of heat involved. In calorimeters, for example, the specific heat...
Specific heat capacity of gases (at constant volume or pressure)
Due to compressibility of gases, a distinction must be made between the isobaric and the isochoric specific heat capacity. Learn more about this in this article.
Differentiation between isochoric and isobaric heat...
Specific heat capacity of water
The specific heat capacity is not a material constant for a substance, but depends on the temperature and above all on the state of matter. The dependence of the specific heat...
Specific heat capacity of selected substances
In this article, learn more about the specific heat capacity of different materials and how it affects the change in temperature over time during a heat transfer.
Definition of the specific heat...
Important remarks on the specific heat capacity
Definition of the specific heat capacity
The specific heat capacity (c) describes the relationship between a transfer of heat (Q) and the associated temperature change (Delta T) of a substance of mass...
Specific heat capacity (derivation and definition)
The specific heat capacity indicates how much heat must be absorbed by a substance of mass 1 kg in order to increase its temperature by 1 K (1 °C). Learn more...
Gulf Stream & global ocean conveyor belt
The Gulf Stream is an ocean current in the Atlantic Ocean which, as part of the earth's global conveyor belt, has a decisive influence on the climate in Northern and Western...
Difference between thermal conductivity, diffusivity, transmittance, resistance and heat transfer coefficient
Learn more in this article about the differences and importance of thermal conductivity, thermal diffusivity, heat transfer coefficient, thermal transmittance and thermal resistance, etc.
Thermal conductivity
Thermal conductivity (lambda) describes the heat transfer...
Why are radiators usually located under a window?
Central heating systems use the principle of thermal convection. The water is heated by a central heater and then transferred to the radiators by means of pumps. It is thus a...
Dimensionless numbers of the boundary layers (Prandtl, Schmidt and Lewis number)
To describe the heat and mass transport, dimensionless numbers are introduced to describe the processes within the boundary layers. Learn more about this in this article.
This article provides answers to the...
Thermal and concentration boundary layer
In addition to the hydrodynamic boundary layer, the thermal boundary layer and the concentration boundary layer also have a decisive influence on the entire heat and mass transport in a flow....
Prandtl number
The Prandtl number is a dimensionless similarity parameter to describe the transport of heat and momentum. Learn more about it in this article.
This article provides answers to the following questions, among...
Lewis number
The Lewis number is a dimensionless similarity parameter to describe heat and mass transport. Learn more about it in this article.
This article provides answers to the following questions, among others
What does...
Calculation of the Nusselt numbers for forced flows over plates and in pipes
In this article you will find formulas for calculating the local and average Nusselt numbers for forced flows over plates and in pipes with circular cross sections.
This article provides answers to...
Heat transfer coefficient for thermal convection
The heat transfer coefficient describes the convective heat transfer from a solid to a flowing fluid and vice versa! Learn more about it in this article.
This article provides answers to the...
Hydrodynamic boundary layer
The hydrodynamic boundary layer of a flow has a decisive influence on heat and mass transport. Learn more about it in this article.
This article provides answers to the following questions, among...
Nusselt number to describe convective heat transfer
The Nusselt number is a dimensionless similarity parameter to describe convective heat transfer, independent of the size of the system. Learn more about it in this article.
This article provides answers to...
Temperature profiles and heat flows through different geometries
In this article we discuss temperature curves and heat flows through a plane wall, through a cylindrical pipe and through a hollow sphere.
This article provides answers to the following questions, among...
Thermal conduction in solids and ideal gases
The thermal conductivity in crystalline, non-metallic solids first increases and then decreases again with increasing temperature. Learn more about this behavior in this article.
This article provides answers to the following questions,...
Laser-Flash method for determining thermal conductivity (LFA)
With the Laser-Flash method (Laser Flash Analyser, LFA), the thermal conductivity is determined by the temperature rise in a test sample that is heated by a short laser pulse from one...
Transient-Hot-Wire method method for determining thermal conductivity (THW)
With the Transient-Hot-Wire method (THW), the thermal conductivity is determined by the change in temperature over time at a certain distance from a heating wire. Learn more about the experimental determination...
Heat-Flow-Meter method for determining thermal conductivity (HFM)
With the Heat-Flow-Meter method (HFM) the thermal conductivity is determined by comparative measurement of the heat flow using a reference sample. Learn more about this absolute measurement method in this article.
This...
Guarded-Hot-Plate method for determining thermal conductivity (GHP)
With the Guarded-Hot-Plate method (GHP) the thermal conductivity is determined by the electrical power output of a hot plate with guided heat conduction. Learn more about this measurement method in this...
Derivation of heat equation (diffusion equation)
The heat equation describes the temporal and spatial behavior of temperature for heat transport by thermal conduction. Read more about it in this article.
This article provides answers to the following questions,...
Thermal conductivity of gases
The thermal conductivity of ideal gases is not dependent on pressure for gases that are not too strongly diluted. This is no longer the case for gases with low pressure. Learn...
Experimental setup for determining thermal conductivity
In this article you can learn more about the experimental determination of the thermal conductivity of materials using steam and ice.
This article provides answers to the following questions, among others
What...
Thermal transmittance (U-value)
The thermal transmittance (U-value or U-factor) describes the heat transfer through a solid object, which is located between two fluids (gas or liquid) with different temperatures. Learn more about it in...
How does a thermos work? Design of a vacuum flask!
The reason why hot tea or coffee stays warm for so long in a thermos is the special design of the flask. This design limits the different mechanisms of heat transfer...
Heat transfer by thermal radiation
With thermal radiation, heat is transferred by electromagnetic waves without the presence of a substance! You can read more about this mechanism in this article.
The mechanisms of thermal convection and thermal...
Heat transfer by thermal convection
With heat transfer by thermal convection, heat is transported with a flowing substance. Convection only occurs in fluids, i.e. gases and liquids. You will find more information in this article.
This article...
Heat transfer by thermal conduction
Heat transfer by thermal conduction means that heat is conducted through a material. Heat energy is transferred from molecule to molecule at the atomic level. More information on this topic can...
Rate of heat flow: Definition and direction
The rate of heat flow refers to the heat energy transferred per unit of time ("heat output"). The drive for the heat flow is a temperature difference. Learn more about the...
Thermal conductivity (Fourier’s law)
Thermal conductivity is a measure of how well or poorly a material conducts heat energy (measure of the strength of heat conduction)! You can read more about this in this article.
This...
Heat and thermodynamic equilibrium
In thermodynamics, heat is the transport of energy due to a temperature difference. Heat in this respect is never "contained" in an object! Learn more about the thermodynamic concept of heat...
Heat transfer (heat transport)
Heat transfer is the transport of thermal energy from a warmer object to a cooler object. A distinction is made between thermal convection, thermal conduction and thermal radiation. You can read...
Why does metal feel colder than wood (human thermal response)
Find out in this article why metal feels colder than wood of the same temperature, while at higher temperatures the metal suddenly feels warmer than wood.
The property of an object to...
