The composite source distribution method can be used to increase calculation efficiency when a model is symmetric.

For a structure with port-starboard and fore-aft symmetry, and are a pair of field and source points on the first quadrant of the hull surface. There are three pairs of corresponding points in the other quadrants:

(4–61)

The source strengths and potentials on these points are denoted as:

(4–62)

The composite source strengths and composite potentials are defined as:

(4–63)

The composite source strengths can be estimated by integrating over the first quadrant of the hull surface, :

(4–64)

where the composite Green functions are defined as:

(4–65)

The composite potential is expressed as:

(4–66)

Once the composite source strength and composite potential are derived, the source strength and the potential at all four pairs of source and field points on the four quadrants of the hull surface can be determined from Equation 4–63:

(4–67)

For a single symmetric structure (a structure with either port-starboard or fore-aft symmetry), and are a pair of field and source points on the first half of the hull surface, and there is a pair of corresponding points on the other half:

(4–68)

The source strengths and potential on these points are:

(4–69)

The composite source strengths and composite potentials are defined as:

(4–70)

Employing the same concept discussed for the double symmetric case, the composite source strengths and composite potentials can be estimated by integrating over the half part of the hull surface. Once these variables are calculated, the source strengths and potentials are obtained by:

(4–71)