DRAG FORCES ON BAFFLE BLOCKS IN A STILLING BASIN (PERGAU POND MODEL IN UTP LABORATORY)

Baffle blocks is one type ofenergy dissipater functioning to dissipate excess kinetic
energy possessed by flowing ofwater. It is also used to protect downstream area by
reducing the velocity of flow to the acceptable limits. Pergau Pond Model was
constructed in UTP Laboratory for investigation of Pergau Regulating Pond failure.
Objective of this work is to conduct a series of laboratory tests to provide for
evaluation ofthe existing empirical relations and possibly come up with new guides
for the magnitude and behavior ofthe forces on the baffle blocks in a stilling basin of
Pergau Pond Model in UTP Laboratory. The work is done by analyze the effect of
different shape, size and discharges to the resulting drag forces. The results obtained
shows that higher the frontal area, A, and height ofblock, higher the drag forces. The
standard USBR block type provide an optimum drag force compared to sloped
trapezoidal shape. It is also proved that higher discharge and velocity value resulting
in higher forces. Drag force coefficient is also analyzed and studied from previous
investigations. Equipment and measurement error have been found during the lab
experimental procedure which affecting the experiment results. Besides, limited
equipment available eliminate the better methods could be implemented while
avoiding satisfied quantity ofdata obtained. The basic factors influencing the drag
force performance has been studied and understood while the knowledge of drag
forces on baffle blocks behavior is acquired.