DISCHARGE MEASUREMENT OF OPEN FLOW USING CURRENT METER

1. DISCHARGE
MEASUREMENT OF OPEN
FLOW USING CURRENT
METER
PRESENTATION OF LAB (ENGINEERING HYDOLOGY)

2. DISCHARGE
 Discharge or rate of flow (Q) is defined as the fluid flowing per second through
a channel or section of a pipe
 The flow rate of a stream is equal to the flow velocity (speed) multiplied by the
cross-sectional area of the flow.
 The equation Q=AV (Q=discharge rate, A=area, V=velocity) is sometimes known
as the discharge equation.

3. EQUIPMETS USED FOR CARRY OUT THE
EXPERIMENT
 CURRENT METER
 TAPE OR ANY LENGTH MEASURING INSTRUMENT
 AN OPEN WATER CHANNEL MAY BE IN LAB OR CAN EXSIST NATURALLY
 SOFTWARES LIKE CFDS OR YOU CAN ALSO PERFORMED MANUALLY BUT THE
CHANCES OF ERROR MAY OCCUR

4. CURRENT METER
 A CURRENT METER IS A MECHANICAL DEVICE WHICH IS USED IN MEASURING THE
FLOW VELOCITY OF THE WATER
 IT HAS MANY TYPES BUT THE MAJOR WORKING OF ALL OF THEM IS SAME
 IT DETECTS THE OVERALL DISTANCE OF A GIVEN CROSS SECTION AREA AND THE
TIME TAKEN BY THE CURRENT METER FOR THIS STETECTION AND THEN IT FIND THE
VELOCITY OF THE CHARGE

5. CURRENT METER

6. THE DETAILED WORKING OF CURRENT METER
 THE METER IS PLACED INSIDE THE WATER SECTION
 DUE DO THE PRESSURE THE ROTOR PART ROATES
 THE NUMBER OF REVOLUTIONS ARE RECORDED
 AS THE ANGULAR VELOCITY IS DIRECTILY PROPERTIONAL TO LINEAR VELOCITY
 THE VALUE OF VELOCITY IS RECOREDED
 υ/ω= r

7. METHODS FOR MEASURING THE DISCHARGE
 AREA VELOCITY METHOD
 MID SECTION METHOD
 BISECTION METHOD
 MEAN AREA METHOD
 APPROXIAMATE METHOD

8. AREA VELOCITY METHOD
 THIS IS THE MOST SIMPLEST AND THE EASY METHOD USED FOR CALCULATING THE
DISCAHRGE
 MOST WIDELY USED
 READINGS MAY HAVE ERROR
 THE ERROR HAS TO BE REMOVED BY USING WELL CALIIBRATED INSTUMRNTS BUT
STILL OUR ANSWER IS NOT EXACTLY CORRECT

9. AREA VELOCITY METHOD
 The most common approach to determining discharge is the so called
conventional current-meter method.
 The method is based on determining the mean streamflow velocity and flow
cross sectional area
 the product of these variables determines the stream discharge

10. AREA VELOCITY METHOD

11. ARAE VELOCITY METHOD
 THE ABOCE DIAGRAM EXPLAINS THE WORKING PROCEDURE OF MEASURING THE
AREA VELOCITY METHOD
 WE DIVUDE THE CROSS SECTIONAL AREA IN SMALLER RECTANGULAR SECTIONS
 THEN BY MULTIPLYING THE WIDTH WITH THE LENTH THA AREA IS CALCULATED

12. ARAE VELOCITY METHOD
 AS THE VELOCITY WAS CALCLATED BY CURRENT METER
 BY PUTTING THE SUMMATION OF ALL AREAS OF RECTANGLE WE GET THE TOTAL
AREA BY USING THE FARMULAE OF DISCHAGE WE GET THE VALUE OF DISCHARGE

13. MEMBERS
 ADEEL ARIAN (51014)
 HAIDER AFRIDI (50494)
 USAMA(50290)
 ZAINAB(48947)
 ABUZAR(50365)