Does arterial blood always flow away from the heart?
Simple answer, yes.

It really is a matter of how technical you wish to be. By defintion, all arterial flow conveys blood away from the heart. The largest arteries exhibit the Windkessel effect which allows for the compression-based effects that bobthejoe inferred. Explicity, as blood is pumped out of the left ventricle, it stretches te aorta, and this tension in turn causes compression on the artery and pushes blood forward. On the flip side, venous vessels (except the pulmonary vein) return blood to the heart, but here you are likely to encounter local areas of reverse flow. This is counteracted to a degree by one-way valves present in the large veins to keep the net movement of blood in the body always toward the heart.