Effect Of Three Types Of Cracks On The Conversion Efficiency Of Thermoelectric Materials

Thermoelectric material is a kind of functional material that can convert electric energy and thermal energy to each other,which plays an indispensable role in engineering.However,due to the limitation of the conversion efficiency of thermoelectric materials,thermoelectric materials cannot be widely used in human production and life for the time being.Therefore,it is particularly important to study methods to improve thermoelectric properties of thermoelectric materials.Based on nolinear thermoelectric theory,the effect of different cracks on the conversion efficiency of thermoelectric materials is studied by using Fourier transform technique and singular integral equation method.Firstly,the development,theoretical basis and thermoelectric performance of thermoelectric materials are briefly introduced.Secondly,the effects of center symmetrical crack,interface crack and through cracks on the conversion efficiency of thermoelectric materials under different boundary conditions are studied.Based on nonlinear coupling electric heat transfer equation,using Fourier integral transform technology,introducing the dislocation function,and the problem is transformed into singular integral equation.The singular integral equation is solved numerically by using Erdogan and Gauss-Chebyshev numerical integration method.By introducing the auxiliary function,the analytical expressions of the electric field and temperature field distribution,as well as the current density and energy intensity factor at the crack tip are obtained,which can help to determine the thermoelectric conversion efficiency.Numerical results show that higher thermoelectric conversion efficiency can be achieved in thermoelectric materials with suitable cracks.The electric field intensity factor and energy intensity factor increase with the increase of the height of the thermoelectric plate surface,but decrease with the increase of the width.