The angular porosity distribution for fixed packed beds of monosized spheres in cylindrical containers with low diameter aspect ratios (1 less than or equal to D/d less than or equal to 2) is determined from the spheres’ center coordinates. By dividing the packed bed into a large number of identical wedge-shaped segments, the angular porosity distribution is established from the local angular porosity and the angular positions within the cylindrical container. A correlation which accurately predicts the local angular porosity is determined from the angular porosity distributions. The correlation is a function of D/d and the angular position in the cylindrical container.