INTRODUCTION WITH FLUMES, WEIRS AND ORIFICES….

Submitted By - Submitted To -

Mr. Rahul Sharma & Mr. Akhil Bharti Dr M.C. Rana (Agron.)

A FLUME IS A MAN MADE CHANNEL FOR WATER, IN THE FORM OF AN OPEN DECLINED GRAVITY CHANNEL WHOSE WALLS ARE RAISED ABOVE THE SURROUNDING TERRAIN, IN CONTRAST TO A TRENCH OR DITCH..SOME VARIETIES OF FLUMES ARE USED IN MEASURING WATER FLOW OF A LARGER CHANNEL…

Flumes….

TYPES OF FLUMES....FLUMES

H-TYPE FLUME

HS TYPE

H TYPE

HL TYPE

PARSHALL FLUME

A WEIR  IS A BARRIER ACROSS A RIVER DESIGNED TO ALTER ITS FLOW CHARACTERISTICS. IN MOST CASES, WEIRS TAKE THE FORM OF OBSTRUCTIONS SMALLER THAN MOST CONVENTIONAL DAMS, POOLING WATER BEHIND THEM WHILE ALSO ALLOWING IT TO FLOW STEADILY OVER THEIR TOPS. WEIRS ARE COMMONLY USED TO ALTER THE FLOW OF RIVERS TO PREVENT FLOODING, MEASURE DISCHARGE, AND HELP RENDER RIVERS NAVIGABLE.

Weirs….

WEIRS

RECTANGULARWEIR

SHARP CRESTED RECTANGULAR

BROAD CRESTED RECTANGULAR

TRIANGULAR WEIR

SHARP CRESTED TRIANGULAR

BROAD CRESTED TRIANGULAR

CIPOLLETTI WEIR

Different Types Of Weirs….

1.A weir will artificially reduce the upstream water velocity, which can lead to an increase in siltation.2.Weirs can also have an effect on local fauna. 3.Even though the water around weirs can often appear relatively calm, they can be extremely dangerous places to boat, swim, or wade, as the circulation patterns on the downstream side—typically called a HYDRAULIC JUMP— can submerge a person indefinitely. This phenomenon is so well known to persons who spend time on rivers that they even have a rueful name for weirs: "drowning machines".4.The weir can become a point where garbage and other debris accumulate.

Drawbacks of weirs……

ORIFICES….

An ORIFICE is a small opening provided in the structure or bulk head put across the channel.The opening are usually circular or rectangular. The orifices are classified as free flow or submerged orifices according to downstream water level is below the bottom of orifice or above top of orifice.Edges of orifice are sharp and made of metal.

DIFFERENT TYPE OF ORIFICES….ORIFICE

RECTANGULAR

RECTANGULAR FREE FLOW

RECTANGULAR SUBMERGED

CIRCULAR

CIRCULAR FREE FLOW

CIRCULAR SUBMERGED

INTERNETNOTES PROVIDED BY OUR RESPECTED PROFFESOR DR. R.S. RANA (Ag Engg).

ACKNOWLEDGEMENT….