Numerical analysis of microscopic coke strength factors using a homogenization method

To investigate the effect of microscopic structures on coke strength, the stress analysis using a homogenization method is carried out for coke with different microscopic textures and pores with various shapes. Analytical results show that stress concentration for pores affects stress field in microscopic region of coke, on the other hand, the diameter and arrangement of inert in coke matrices hardly affects the stress field. The stress concentration for pores is the main factor of lowering coke strength since the interference of the stress concentration causes an increase in the maximum stress and a decrease in the homogenized elastic modulus. Especially, the existence of pores with low roundness causes a decrease in the homogenized elastic modulus of coke drastically and its effect on coke strength is bigger as the pore size is larger. Thick pore wall gives a decrease in maximum stress and an increase in the homogenized elastic modulus. In addition, in the case of pores with low roundness, the existence of big pores counteracts an increase in the homogenized elastic modulus with thick pore wall.