Final control questions on the subject “heat engineering” The purpose and function of the subject. Working parameter. Status parameters. Base words and phrases

 
Base words and phrases: temper, balloon, optional shape, heat quantity, formulas 
Thermal conductivity is an important property in material science that determines the ability of a 
material to conduct heat. The thermal conductivity of a complex-shaped body refers to the 
ability of that body to transfer heat when exposed to a temperature gradient. 
When dealing with complex-shaped bodies, such as a balloon or an object with an irregular shape, 
calculating thermal conductivity can be difficult. However, there are some formulas that can 
be used to estimate thermal conductivity in these situations: 
1. Fourier's Law: This law provides an equation that relates thermal conductivity to heat flow. It 
states that the rate of heat transfer through a body is proportional to the thermal conductivity 
of the material, the area through which heat is transferred, and the temperature difference on 
either side of the material. 
2. Equivalent Thermal Resistance Formula: This formula estimates the thermal conductivity of a 
complex-shaped body through the use of equivalent thermal resistance. It relates the thermal 
resistance to the thickness and shape of the material being considered. The equivalent thermal 
resistance is then used along with Fourier's law to estimate the amount of heat transferred 
through the complex-shaped body. 
3. Finite Element Analysis: This is a numerical method used for solving thermal conductivity 
problems in complex-shaped bodies. It divides the complex-shaped body into small elements 
and solves a heat transfer problem numerically for each element. The resulting temperatures 
and thermal conductivities are then used to estimate the thermal conductivities of the complex-
shaped body as a whole. 
Overall, calculating thermal conductivity of complex-shaped bodies such as balloons and objects 
with irregular shapes requires the use of specific formulas that take into consideration the 
temperature differences, area, and other physical parameters of the material being considered. 
The choice of formula may depend on the shape of the body, the amount of heat being 
transferred, and the precision of the estimation required. 
26. Free and forced convection.