Mann and Hummel Employs Aeroprobe Equipment to Improve Manifold Performance

The flow through bent pipes generates uneven velocity and pressure distributions and large-scale vortical structures. Intake engine manifolds that are bent sharply may lead to non-uniform flow entering the engine cylinders. To explore these effects in the design of a 56 mm, 135o–bend manifold pipe, Mann and Hummel of Brussels employed an Aeroprobe seven-hole probe with a 1.6 mm probe tip, and traversed it along four planes of the pipe, with three manifold-vane configurations. In the figures below, two views of the pipe are shown.

The results are presented in the following two figures in terms of velocity vectors within the planes arranged normal to the local axis of the pipe. The in-plane velocity components are presented in terms of arrows, while the axial component is represented by color contours. The effect of a vane is analyzed. On the left frame the axial component favors heavily the right portion of the pipe cross-section. Adding a guide vane redistributes the axial flow in the pipe as shown on the right frame. Mann and Hummel employed information obtained in their experiments to improve the operation of their manifolds.

Axial Velocity Contours: No Vane (Left), Vane #2 (Right); Data Courtesy of Mann+Hummel, Brussels