Area 2 - Open Channel Flashcards
PART 4: Objective type on open channels
a conduit in which liquid flows with a free surface
open channel
a type of flow having a free surface and subjected to atmospheric pressure.
open channel flow
a type of flow confined in a closed conduit, has no free surface and exerts no direct pressure but hydraulic pressure only
pipe flow
if the depth of flow does not change or if it can be assumed to be constant during the time interval under consideration
steady flow
it is a flow that changes with time
unsteady flow
if the depth of flow is the same at every section of the channel
uniform flow
uniform flow is also referred to as _____. fundamental type of flow in open channels hydraulics
steady uniform flow
if the depth of flow changes along the length of the channel
varied or non-uniform flow
varied or non-uniform flow is also known as ______, where water runs in or out along the course of flow.
spatially varied or discontinuous flow
example of varied or non uniform flow
roadside gutters, side-channel spillways, washwater trough in filters, effluent channels around sewage-treatment tanks
specific energy equation (Froude no. = 1)
critical flow
factors that affect open channel flow
viscosity, gravity
together with gravity, they are the factor that basically affect open-channel flow
viscosity
what are the types of flow in terms of the effect of viscosity relative to inertia.
laminar, turbulent, transitional
water particles appear to move in definite, smooth paths, or streamlines; and extremely thin layers of fluid slide over adjacent layers
laminar
viscuous forces are weak relative to inertial forces; water particles move in irregular paths which are neither smooth nor fixed
turbulent
the effect of viscosity relative to inertia can be represented by the
reynold’s number
if the depth of flow is taken as the characteristic length, R < 500
laminar flow