The method of deriving the optional curve according to the floating matter accumulation and density model
H-R curve is commonly used to describe the washability of raw coal,including float accumulation curve,sediment accumulation curve,elementary ash curve,density curve and adjacent matter content curve.Firstly,the mathematical model of the floating accumulation curve and the density curve is established by the method of curve fitting,and then the other curves are calculated by the mathematical model of the floating accumulation curve and the density curve.Among them,the elementary ash curve is a differential curve.Generally,the approximate method is used to draw the elementary ash curve and calculate the elementary ash,and there is a certain error.In this paper,the mathematical expression of the elementary ash curve is obtained by using the mathematical model of the floating accumulation curve and the mathematical derivation method,which reduces the calculation error.