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SRI SIVASUBRAMANIYA NADAR COLLEGE OF ENGINEERING,

KALAVAKKAM- 603110.

FLUID MECHINERY LAB

SECOND CYCLE EXPERIMENTS

1. CALIBRATION OF ROTAMETER

2. MINOR LOSSES IN PIPE FLOW

3. VERIFICATION OF BERNOULLIS THEOREM

4. FLOW THROUGH V-NOTCH

5. PERFORMANCE TEST ON PELTON WHEELTURBINE

6. PERFORMANCE TEST ON KAPLAN TURBINE

7. PERFORMANCE TEST ON FRANCIS TURBINE

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1. CALIBRATION OF ROTAMETER AIM:

To conduct experiment on Rotameter at different flow rate and to calibrate the meter.

APPRATUS REQUIRED:

Stop watch, meter scale

PROCEDURE:

1. Open the inlet valve to allow flow through the Rotameter.

2. Collect the water in the collecting tank for a rise of 10cm and note the time t1 seconds.

3. Note the Rotameter reading, Qm (lpm)

4. Repeat steps 1to3 at least for five sets of reading.

5. Enter all readings in table of observations and calculations.

FORMULA USED:

1. Area of collecting tank, L x B (m2)

2. Actual discharge, Qa = [LBy x 60 x1000] / t1 (lpm)

3. Rate of Discharge = Qm in (lpm)

4. Error percentage = [(Qa Qm) / Qm ] x 100 %

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MODEL CALCULATION:

1. Area of collection tank = L x B = ________ (m2) 2. Actual discharge Qa = [LBy x 60x1000] / t = ________ (lpm) 3. Discharge from Rotameter Qm = ________ (lpm) 4. Error in % = [(Qa Qm) / Qm ] x 100 %

Tabulation: 30 LPM Rotameter

S.

No

Rate of Discharge through

Rotameter Qm

Time takenm for 10

cm rise, t1

Rate of actual

discharge Qa

Error in meter

[(Qa/Qm) -1]*100

Unit lpm s lpm %

1

2

3

4

5

Length of collecting tank = 30 cm

Breadth of collecting tank = 30 cm

Tabulation: 20 LPM Rotameter

S.

No

Rate of Discharge through

Rotameter Qm

Time takenm for 10

cm rise, t1

Rate of actual

discharge Qa

Error in meter

[(Qa/Qm) -1]*100

Unit lpm s lpm %

1

2

3

4

5

Length of collecting tank = 30 cm

Breadth of collecting tank = 30 cm

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Graphs:

Plot the graph between % errors Vs Qm.

RESULT:

Thus the test was conducted on the Rotameter and the percentage error has been calculated.

Average error in 20 lmp rotameter = _______ %

Average error in 30 lmp rotameter = _______ %

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2. MINOR LOSSES IN PIPE FLOW AIM: To determine the minor losses in a flow through pipe. APPARATUS REQUIRED: Meter scale Stop Watch PROCEDURE: Measure the diameter of pipe. Also measure the dimensions of the collecting tank. Connect the manometer across the sections for which the loss of head due to expansion is to be measured. Open the inlet valve Gradually adjust the existing valve when the flow becomes steady, measure the manometric deflection (h). Take the initial reading of the tank and start the stop watch note the rise. Repeat the above steps for different discharge. FORMULA USED:

The loss of head due to expansion, Hle = Ke(V1-V2)2/2g Where V1 velocity in smaller pipe, and V2 Velocity in larger pipe Ke Coefficient of expansion The loss of head due to contraction, Hlc= Kc (V12/2g) Where V1 velocity in smaller pipe, and Kc Coefficient of contraction The loss of head due to bend, Hlb = Kb (V2/2g) Where V velocity in pipe, and Kb Coefficient for bend

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Tabulation: Sudden expansion of pipe

S. No.

Manometer reading Time for 10 cm rise in water (s)

Discharge (m3/s)

V1 (m/s)

V12/2g (m)

V2 (m/s)

V22/2g (m)

Ke h1 (m)

h2 (m)

h= h1-h2 (m)

Hle = [Sm/Sw -1] h (m)

Tabulation: Sudden contraction of pipe

S. No.

Manometer reading Time for 10 cm rise in water (s)

Discharge (m3/s)

V1 (m/s)

V12/2g (m)

Kc h1 (m)

h2 (m)

h= h1-h2 (m)

Hlc = [Sm/Sw -1] h (m)

Tabulation: Bend in pipe

S. No.

Manometer reading Time for 10 cm rise in water (s)

Discharge (m3/s)

V1 (m/s)

V12/2g (m)

Kb h1 (m)

h2 (m)

h= h1-h2 (m)

Hlb = [Sm/Sw -1] h (m)

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MODEL CALCULATION: Sudden Expansion Q = LBy/t1 = ________ (m3/s) Hle = [Sm/Sw -1] h = ________ (m) V2 = Q/A 2 = __________ (m/s) V1 = Q /A1 = __________ (m/s) Ke = Hle / (V12- V22) /2g = ______

Sudden Contraction Q = LBy / t1 = ________ (m3/s) Hlc = [Sm/Sw -1] h = ________ (m) V1 = Q /A1 = __________ (m/s) Kc = Hlc / (V12 /2g) = ______ Loss in bend Q = LBy / t1 = ________ (m3/s) Hlb = [Sm/Sw -1] h = ________ (m) V = Q /A = = ________ (m/s) Kb = Hlb / (V2 /2g) = ________

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RESULT: Coefficient of expansion, Ke = _________ Coefficient of contraction, Kc= _________ Coefficient of bend, Kb = _________

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3. VERIFICATION OF BERNOULLIS THEOREM

AIM: To verify Bernoullis theorem using Bernoullis apparatus. APPARATUS REQUIRED: Bernoullis apparatus, stop watch PRINCIPLE : In an incompressible fluid flowing steady and continuous the sum of pressure energy and potential energy is constant p/g +v2/2g + z = constant PROCEDURE: The electric motor is started and the water is allowed to flow in the divergent and convergent position. By adjusting the outlet valve the pressure head of water taken for 10 cm rise in the collecting tank is noted. The length and breadth of every consecutive tubes lower portion are calculated using meter scale. Then by using Bernoullis equation the Bernoullis theorem is verified. FORMULA USED: p/g +v2/2g +z = constant p/g pressure head v2/2g- velocity head z datum head

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TABULATION:

S. No

Cross sectional area

Time for 10 cm rise, t (s)

Qa (m3/s) Local velocity, V

Velocity head, V2/2g (m)

Pressure head (m)

Total head, H (m)

MODEL CALCULATION: Qa = LBy/t = _________ (m3/s) V = Qa/A = _________ (m/s) Velocity head = V2/2g = _________ (m) Total Head (H) = p/g +V2/2g +z = _________ (m)

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GRAPH: The graph was plotted by taking area of cross section on x-axis Vs Velocity head, Pressure head and total head on y-axis. RESULT: Thus the Bernoullis theorem was verified using Bernoullis apparatus.

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4. FLOW THROUGH V- NOTCH AIM: To determine the coefficient of discharge (Cd) of V-notch. APPARATUS REQUIRED: Notch tank V-Notch Hook Gauge Collecting tank Stop watch Piezometer Meter scale PROCEDURE: The dimension of the collecting tank is measured. The supply valve is fully opened water is allowed to fill up to sill of the V-notch. Sill level reading (h1) is noted by adjusting the tip of the hook gauge to just touch the water surface. The supply valve is fully opened and the water is allowed to flow through the v-notch. The tip of the hook gauge is so adjusted to just touch the free surface of the flowing water and the reading (h2) is noted. The outlet valve of the collecting tank is closed and the time taken for the 10 cm rise of water level in piezometer is noted. The procedure is repeated for five different discharge conditions and the readings are tabulated. FORMULA USED: Coefficient of discharge (Cd) = Qa/Qth Qa = LBy/t (m3/s) Theoretical discharge through V- notch, Qth = 8/15 tan (/2) 2g H5/2 (m3/s) Where, = angle of V-notch in degrees H=head above the sill of the notch in m. g = acceleration due to gravity L = length of the collecting tank B = Breadth of the collecting tank h = rise of water level in collecting tank

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TABULATION:

S. No.

Hook Gauge readings (cm)

Head over the notch

(cm)

Time for 10 cm

rise, t (s)

Discharge x 10-4 (m3/s) Coefficient of discharge (Cd)

H1 H2 H Qa Qth 1 2 3 4 5 6

MODEL CALCULATION: Actual discharge (Qa) = LBh/t Theoretical discharge through V- notch, Qth = 8/15 tan (/2) 2g H5/2 Coefficient of discharge (Cd) = Qa/Qth

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GRAPH: Graph is plotted by taking log10H5/2 on x-axis and log10Qa on y-axis. RESULT: The coefficient of discharge of V-notch, From tabulation: From log graph:

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5. PELTON WHEELTURBINE

AIM:

To study the characteristics of Pelton wheel turbine at constant head.

APPARATUS REQUIRED:

Pelton wheel turbine, Pump set, Venturimeter fitted with pressure gauge, Tachometer, Weight, Hanger,

Spring balance and pressure gauge.

PROCEDURE:

1. Note the system details,

(a) Diameter of the break drum (D) in m (b) Diameter of rope (d) in m

2. Loosen the break wheel so that the needle in the spring balance read zero.

3. Open the gate valve fully

4. Adjust the speed for constant nozzle opening.

5. Start the pump supply.

6. Apply 1 kg load initially and note the following observations

(a) Pressure gauge readings (P1& P2) of venturimeter. (b) Pressure gauge readings at entrance of turbine. (c) Reading shown by the spring balance. (d) Tachometer reading.

7. Repeat the observations for at least six different readings.

8. After all observations are made unload the weights gradually and switch off the supply pump motor.

9. All observations are be tabulated

FORMULA:

1. Supply head H = Pd (m).

H = head of water (m)

2. Discharge Qa = 39 h / (60x1000) (m3/s)

Qa = discharge in m3/s, h= Venturi head in (mm).

3. Input power (IP) =wQH/1000 (kW)

H = Total head (m)

4. Output power (OP) = 2 NT / (60x1000) kW

N- Turbine speed in rpm

T- Torque in N.m (effective radius of the break in m, break load in N)

5. Efficiency () = OP /IP x 100

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MODEL CALCULATION FOR PELTON WHEEL TURBINE:

1. Venturimeter pressure gauge readings P = (P1 P2) = ______ kg/sq.cm. h = (P x104 x9.81) / (9810x1000) = ______ (mm). 2. Actual discharge Qa = 39 h / (60x1000) (m3/s). = 39 ____ / (60x1000) = _____ (m3/s).

3. Supply head H = Pg = (_Pg x 104 x 9.81) / 9810 = ________ (m)

4. Toque T = 9.81xW x R (Nm) = 9.81x ______ x 0. 165 = _______ (Nm)

5. Out put power OP = 2 NT /(60x1000) kW. = (2x x _____x_____) / (60x1000) = _______ (kW). 6. Input power IP = wH Qa / 1000 kW. = ( 9810x _____x____) / 1000 = _______ (kW). 7. Efficiency () = OP /IP x 100 = (___ /____) x 100 = _______ %

OBSERVATION TABLE FOR PELTONWEELTURBINE

Venturimeter Reading

Pressure Gauge

Speed of

Break Drum

Break Drum Load Added

Actual discha

rge Head Torque IP OP

Efficienc

y

Sl..No P1 P2

P= (P1-P2)

Pg N W1 W2 W=(W1-

W2) Qa H=Pg T IP OP

kg/cm2 kg/cm2

kg/ cm2

kg/ cm2 rpm kg kg kg m

3/s m Nm kW kW %

Break drum diameter = 310 mm Rope diameter = 16 mm

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GRAPH: Draw graph N (in rpm) on X-axis Vs , IP & H. RESULT: Maximum efficiency = _________ % Corresponding speed = ________ rpm Corresponding input power = _______ kW. Corresponding head = _________ m.

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6. KAPLAN TURBINE

AIM:- To study the characteristics of Kaplan turbine under constant head condition

APPARATUS REQUIRED:-

Kaplan turbine, Pump set, Venturimeter fitted with pressure gauge, Tachometer, Weight, Hanger, spring balance and pressure gauge.

PROCEDURE:-

1. Keep the delivery gate valve opening at about 3/8 th open position.

2. Close the delivery gate valve completely and start the pump.

3. After the motor is running of normal speed, open the delivery gate valve and adjust the inlet pressure.

4. Note the venture meter pressure gauge readings

5. Note the speed of the turbine.

6. Load the turbine by adding weight to the break drum.

7. Repeat the experiment for different loadings

FORMULAE USED:-

1. DISCHARGE

Venturimeter pressure gauge readings P = (P1 P2) kg / sq.cm.

h = (P x104 x 9.81) / (9810x1000) in (mm)

Q = 40h / (60x1000) m3 / s

Where, h = Venturi meter head (mm)

2 INPUT POWER (IP) Total head H = Hin + Hout (m)

Hin = (Pin x 9.81 x 104) / 9810 (m)

Hout = (Pout x 13.6) / 1000 (m)

Where, Hin = Inlet pressure (kg/cm2), Hout = outlet pressure mm of Hg

6. IP = wQH/1000 (kW)

Where, H = Total head (m), Q= Discharge (m3/s)

3.OUTPUT POWER (OP)

OP = (2NT/(60x1000) (kW)

Where, N= Speed of the turbine in rpm

Torque, T= 9.81*W*R (Nm)

W = Weight (kg), R = Radius of brake drum, (m)

4.EFFFICIENCY IF THE TURBINE

Efficiency = (OP / IP) *100%

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MODEL CALCULATION FOR KAPLAN TURBINE

1. Total head H = Hin + Hout (m)

Hin = (Pin x 9.81 x 104) / 9810 = ___________ (m)

Hout = (Pout x 13.6) / 1000 = __________ (m)

2. Venturimeter pressure gauge readings P = (P1 P2) kg / sq.cm. h = (P x104 x 9.81) / (9810x1000) = _____ mm 2. Actual discharge Qa = 40h / (60x1000) = ______ m3/s.

3. Toque T = 9.81x W x R = ______ Nm

4. Out put power OP = 2 NT / (60x1000) = ________ kW. 5. Input power IP = wxHx Qa / 1000 = 9810xHx Qa /1000 = _____ kW 6. Efficiency = OP /IP x 100 = ______ %

Observations:

S

No

Inlet

press

ure

(Pin)

Outlet

press

ure

(Pout)

Total

Head Venturimeter

Speed

of the

turbine

Rope brake dynamometer

Disch

arge IP OP

Effici

ency

kg/c

m2

mm

of Hg m

P1 kg /

cm2

P2

kg /

cm2

P= P1-

P2 kg /

cm2

rpm

Weig

ht

W1

Spring

balance

W2

Net load

w m3/s kW kW %

1

2

3

4

5

Break drum diameter = 0.15m

rope diameter= 0.015m

Weight of the hanger to=1kg

Nozzle opening 3/8th open position

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GRAPH:

Draw graph N (in rpm) on X- axis Vs , IP & H.

RESULT:

Maximum efficiency = __________%

Corresponding head = __________m

Corresponding input power = __________kW.

Corresponding speed = _________ rpm

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7. FRANCIS TURBINE AIM: To study the characteristics of Francis turbine at constant head. APPARATUS REQUIRED: Francis turbine, pump set, Venturimeter fitted with pressure gauge, Tachometer, Weights, Hanger, Spring balance and pressure gauge vacuum gauge. PROCEDURE:

1. Note the system details,

b) Diameter of the brake drum (D) in m

c) Diameter of rope (d) in m

2. Loosen the break wheel so that needle in the spring balance reads zero.

3. Open the gate valve fully.

4. Adjust the speed for constant nozzle opening.

5. State the pump supply.

6. Apply 1 kg load initially and note the following observations

a) Pressure gauge readings (P1&P2) of venturimeter

b) Pressure gauge readings at entrance of turbine.

c) Suction gauge reading at exit of turbine.

d) Reading shown by the spring balance.

e) Tachometer reading.

7. Repeat the observations for at least six different readings.

8. After all observations are made unload the weight gradually and switch off the supply pump motor.

9. All observations are to be tabulated

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.

FORMULAE:

1. Supply head H = Hin + Hout (m)

H = Head of water (m).

Hin = Pin * 104 * (9.81/9810) (m)

Hout = Pout * (13.6/1000) (m)

2. Discharge Qa = 84.5 h /(60x1000) = ______ (m3/s)

Qa = Discharge in (m3/s), h = Venturi head in mm.

Venturimeter pressure gauge readings P = (P1 P2) kg / sq.cm.

h = (P x104 x 9.81) / (9810x1000) in (mm)

3. Input power = (wH Q)/1000 kW.

4. Output power = 2NT / (60x1000) kW.

N= Turbine speed in RPM.

T = Torque =9.81xWxR (Nm). (Effective radius of the break in meters x brake load in kg.)

5. Efficiency, () = OP /IP x 100

Observations:

S

No

Inlet

press

ure

Outlet

press

ure

Total

Head Venturimeter

Speed

of the

turbine

Rope brake dynamometer

Disch

arge IP OP

Effici

ency

kg/c

m2

mm

of Hg m

P1 kg /

cm2

P2

kg /

cm2

P1-p2

kg /

cm2

rpm

Weig

ht

W1

Spring

balance

W2

Net load

W=(W1

- W2)

m3/s kW kW %

1

2

3

4

5

Break drum diameter = 310 mm

Rope diameter = 160 mm

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MODEL CALCULATION:

1. Total head H = Hin + Hout (m)

H = Head of water (m).

Hin = Pin * 104 * (9.81/9810) = ____________ (m)

Hout = Pout * (13.6/1000) = ________ (m)

2. Discharge Qa = 84.5 h/(60x1000) = ___________ (m3/s)

Qa = Discharge in (m3/s), h = Venturi head in mm.

Venturimeter pressure gauge readings P = (P1 P2) kg /sq.cm.

h = (P x104 x 9.81) / (9810x1000) in (mm)

3. Input power = (wH Q )/1000 kW.

4. Output power = 2NT / (60x1000) kW.

N= Turbine speed in RPM.

T = Torque =9.81xWxR (Nm). (Effective radius of the break in meters x brake

load in kg.)

5. Efficiency, () = OP /IP x 100

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GRAPH:

Draw graph N (in rpm) on X- axis Vs , IP & H.

RESULT:

Maximum efficiency = ___________%

Corresponding head = _________ m

Corresponding input power= _________ kW.

Corresponding speed= __________ rpm

CALIBRATION OF ROTAMETERPELTON WHEELTURBINEMODEL CALCULATION FOR PELTON WHEEL TURBINE:MODEL CALCULATION FOR KAPLAN TURBINE

7. FRANCIS TURBINE