Maximum Velocity Location and Pressure Drop of Fully Developed Laminar Flow in Circular Sector Ducts

Abstract

Circular sector ducts have become increasingly important as they continue to appear as flow passages in multipassage tubes. They also represent the limiting cases of internally finned tubes have equispaced, full tapered fins. There are no published data for the maximum velocity u{sub max} and its location (r*). For developing laminar flow, this information is very useful in determining hydrodynamic entrance length based on the velocity at r* attaining a particular percentage of the fully developed value. Unlike that of symmetric ducts such as the circular tube and rectangular ducts, the maximum velocity of the circular sector duct occurs away from the centroid on the axis of symmetry. The purpose of this note is to present the results of u{sub max} and r* and to extend the value for fanning friction factor and incremental pressure drop for apex angles up to 2{pi}.