State Conduction

Among the two key methods of heat conduction in thermal energy, steady-state conduction is one of the most important concepts to be studied. Since thermal conductivity itself is an important property of matter, steady-state conduction and its related concepts can help us understand their relevance with respect to thermal conductivity and its wide-ranging applications.  

In the article below, we will explore what is steady-state conduction and all the important concepts related to it. 

Meaning of steady-state conduction

Steady-state conduction, in contrast to transient heat transfer, is characterised by the transfer of heat with a constant rate of heat transfer throughout the object. Simply put, the temperature remains the same throughout the duration in steady-state conduction. 

Irrespective of the transfer mode, the rate of heat flow remains the same at every given point in time in case of a steady-state heat transfer. It can also be explained in terms of the temperature that flows through an object and treating it as a variable while the temperature of the other system remains constant. However, this stage usually comes when the thermal equilibrium is achieved during heat transfer. 

Examples of steady-state conduction

One of the first real-life steady-state conduction examples is an insulated house. It provides resistance to the flow of heat and can easily reduce the cooling cost and heating. In addition to this, it also provides good comfort and strengthens energy efficiency.

• The most common materials that can be used for insulation include a layer of lower conductivity material that is added to the walls.
• Heat usually flows from all significant living spaces that are adjacent to each other, especially during the winter season.

Among the second and most commonly found steady-state conduction examples is the heating up of laptops. It is an extremely common problem that users usually face in their day-to-day life. However, it is a serious issue and designers must consider it while designing the outlay of the product. 

Upon getting neglected, it may also lead to severe injuries and other critical safety issues. Although a lot of modern-day laptops come with a cooling fan attached to the internal parts of a laptop, which is meant to balance the temperature.

In the case of laptops, the temperature-dependent thermal conductivity is usually designed for the central processing unit parts while the orthotropic thermal conductivity is meant for the PCB. The rest of the part is usually paired with isotropic thermal conductivity and constant thermal conductivity. 

Steady-state conduction in plane walls

In the case of plane walls, steady-state conduction takes place differently. Energy is transferred from comparatively more energetic particles to lesser energetic ones, and the interactions taking place between the particles do not remain constant. One of the prominent steady-state conduction examples that can be taken here is a large plane wall. In such cases, heat transfer is the only possible energy introduction that can take place given that the energy balance for the object is expressed in terms of steady-state operation.

Apart from this, the rate of heat conduction through the layers of such objects is usually proportional to the difference in temperature across various layers and areas where heat transfer takes place. However, this is usually inversely proportional to the layer’s thickness. 

Thermal conductivity

With relevance to the discussion, thermal conductivity can be defined as a figure that measures the ability of a material to transfer heat through it. It is also defined in terms of the heat transfer rate that can be passed through a unit thickness of material per unit area and per unit distance of temperature 

Several properties of thermal conductivity include –

• It keeps on changing with different temperatures and is identified through different experiments.
• The thermal conductivity of different materials shows a significant change in their temperatures around the figure of 0. It is around this stage that these objects usually become superconductors.
• This process is usually compatible with isotropic materials that cause the same properties in almost all directions.
• It is also compatible with most of the insulators that are primarily used to generate resistance towards heat flow. They possess low levels of thermal conductivity and thus, do not allow electricity to easily pass through them. 

Meaning of steady-state thermal analysis

Analysis of fluctuations in the properties of a substance in a constant temperature is known as steady-state thermal analysis. In chemistry, steady-state refers to the stage where a chemical reaction has a constant concentration of its immediate product and the rate of reaction can be determined using the rate-determining step. 

However, this can be done only in case a certain chemical reaction is occurring at different levels. Although this process is usually slower as compared to others, it is still possible to analyse the reaction steps that can be recognised. In case it is not recognisable, we consider the immediate product with a constant concentration for a shorter duration.

Conclusion

In a nutshell, it can be concluded that steady-state conduction is in contrast with the concept of transient heat transfer. Steady-state conduction is said to adjust when the temperature of an object at all given areas and point of time remains constant and does not change. Studying the significance of steady-state thermal analysis is equally important because it enables us to analyse the fluctuations in properties of the given substance through which thermal conductivity happens. Thus, steady-state conduction is an important phenomenon to be studied in detail to understand the involved peculiarities and their applications in real-life examples.