Problem arises from solving a system of equations obtained by conserving energy at each node of a network and equating the net pressure drop around any closed flow loop to zero. The flow field is turbulent and buoyancy forces are important. Linear systems from a Newton-Raphson linearization of this problem.

An interesting characteristic is that the solution of the linearized system by MA28 is remarkably insensitive to changes in the threshold parameter.

Matrices in this set:

HOR 131 (real unsymmetric, 434 by 434, 4710 entries)