EXPERIMENT NO. 2
ROTARY PUMP
LANZADERAS, John Edward P.
Date of Performance: 03/15/2023
2016131632
Date of Submission: 03/22/2023
ME152L-2/E01
10
Engr. Teodulo A. Valle
Instruct
1
TABLE OF CONTENTS
OBJECTIVES
THEORIES AND PRINCIPLES
LIST OF APPARATUS
PROCEDURES
SET-UP OF APPARATUS
FINAL DATA SHEET
SAMPLE COMPUTATIONS
TEST DATA ANALYSIS
CONCLUSION
RECOMMENDATION
REFERENCES
PRELIMINARY DATA SHEET
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OBJECTIVES
1. To know the basic principle and operation.
2. To determine the pump system parameters when subjected to varying suction
water level and speed.
THEORIES AND PRINCIPLES
A positive displacement pump is a rotary pump. Each rotation of the pump moves a set
amount of fluid. Rotary pumps, like other positive displacement pumps, do not require priming
and, unlike centrifugal pumps, perform well under a wide range of circumstances. Rotary pumps
are designed to prevent possible leakage by providing a minimal clearance space between the
moving and stationary sections of the pump. This design method reduces leakage from the
discharge to the suction side. This is also why rotary pumps are frequently run at moderate
speeds to maintain consistent clearance, as faster rates cause more wear and tear on the
components, potentially resulting in an increase in clearance space and diminishing the pump's
efficiency. Since they are positive displacement pumps, rotary pumps are also better suited for
applications with fluctuating pressures, flow rates, and viscosity. Additionally, rotary pumps
outperform conventional positive displacement pumps when dealing with high viscosity fluids.
In compared to other pumps, they can transport these high viscosity fluids with a smaller
efficiency reduction.
Figure 1. Rotary Pump
There are several types of rotary pumps. The vane type is one of the most well-known
and widely used. Although rotary vane pumps are available in a variety of designs, they all have
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similar properties and operate in the same way. Because of the design and placement of the rotor
and vanes in this scenario, the pump creates a crescent-shaped hollow. This chamber is
responsible for the pump's high suction. The flexible member rotary pump is another rotary
pump type. This type of pump's vanes bend rather than glide, making it comparable to vane
pumps. This is because rubber vanes were employed in this instance. Owing to the design on the
internal half of the pump, this flexible vane creates suction in the pump. The screw pump is the
final type of pump I'll discuss in this section. As the name indicates, this type of pump delivers
fluid by a screw or sequence of screws. The screw turns in a clockwise manner.These are the
formulas used in this experiment:
Pump Discharge
𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 (𝑣𝑜𝑙𝑢𝑚𝑒) =
𝑚𝑎𝑠𝑠
𝑑𝑒𝑛𝑠𝑖𝑡𝑦
Total Dynamic Head
𝑇𝐷𝐻 = 𝐻𝑑 − 𝐻𝑠
Dynamic Discharge Head:
𝐻𝑑 =
𝑃𝑑
δ
+
𝑉𝑑
2
2𝑔
+ 𝑍𝑑 + ℎ𝑓𝑑
Dynamic Suction Head:
𝐻𝑠 =
𝑃𝑠
δ
2
+
𝑉𝑠
2𝑔
+ 𝑍𝑠 + ℎ𝑓𝑠
Velocity of Water:
𝑉=
𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦
𝐶𝑟𝑜𝑠𝑠−𝑠𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝐴𝑟𝑒𝑎
Water Power: 𝑊𝑃 = 𝑄 𝑥 δ 𝑥 𝑇𝐷𝐻 𝑥 𝑆. 𝐺
Power Input: 𝑃𝐼 = 3𝐸𝐼𝑐𝑜𝑠θ
Brake Horsepower:
𝐵𝑃𝑃 = 𝑛𝑚𝑛𝑡𝑃𝐼
( )𝑥 100%
=(
)𝑥 100%
Pump Efficiency: η𝑃 =
Overall Efficiency: η𝑜
𝑊𝑃
𝐵𝑃
𝑊𝑃
𝑃𝐼
2
LIST OF APPARATUS
1. Rotary Pump
Figure 2. Rotary Pump
2. Electric Motor
Figure 3. Electric Motor
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3. Steel tank/drum
Figure 4. Steel tank
4. Pressure Gauge
Figure 5. Pressure Gauge
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5. Platform Balance
Figure 6. Platform Balance
6. Set of Counterweights
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Figure 7. Set of Counterweights
7. Amprobe
Figure 8. Amprobe
8. Steel tape
Figure 9. Steel tape
9.
Stopwatch
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Figure 10. Stopwatch
10. Tachometer
Figure 11. Tachometer
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PROCEDURES
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SET-UP OF APPARATUS
Figure 12. Set-up of the experiment
Figure 13. Measuring the rpm
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Figure 14. Determining the PSI
Figure 15. Filling up the Tank
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Figure 16. Measuring the Line Current
Figure 17. Recording the Weight of the Water
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FINAL DATA SHEET
Trial
1
2
3
4
5
Pressure, psig
2
2
2
2
2
Suction water
level, inches
44
41 1/2
39
37.5
34.0
Pump Speed,
rpm
847
890
889
1335
1337
Discharge
Capacity, kg/s
1.093
0.873
0.797
70.0
69.0
Line Current,
amp
8.3
7.8
7.7
0.69
0.71
TDH, feet
3.082
3.0145
3.47
11.03
11.31
Waterpower,
hp
0.0135
0.01245
0.01
0.052
0.052
Power Input,
hp
3.39
3.187
3.15
0.28
0.29
Brake Power,
hp
2.88
2.44
2.67
0.22
0.225
Pump Eff, %
0.529
0.311
0.46
23.64
23.11
Overall Eff, %
0.398
0.391
0.35
18.57
17.93
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SAMPLE COMPUTATION
Trial 1
Discharge Head
𝑣𝐷 =
𝐻𝐷 =
𝑃𝐷
γ
𝑄
𝐴
=
(1.093 )(
)(
( )(1.5 𝑖𝑛 𝑥 )
𝑘𝑔
𝑠
π
4
+
2𝑔
(2 )(
+ 𝑧𝑑 + ℎ𝑓𝑑 =
𝑖𝑛
3
(3.2808 𝑓𝑡)
3
1𝑚
2
1 𝑓𝑡
12 𝑖𝑛
𝑙𝑏𝑓
2
𝑣𝐷
3
1𝑚
1000 𝑘𝑔
144 𝑖𝑛
2
62.34
1 𝑓𝑡
𝑙𝑏𝑓
2
2
)
)
+
= 3. 145
𝑓𝑡 2
𝑠
(3.145 )
(
2 32.2
3
𝑓𝑡
𝑓𝑡
𝑠
2
)
𝑓𝑡
𝑠
(
+ 28
𝐻𝐷 = 7. 002 𝑓𝑡
Suction Head
𝑣𝑠 =
𝑄
𝐴
=
(1.0093 )(
𝑘𝑔
𝑠
π
4
3
1𝑚
1000 𝑘𝑔
( )(2 𝑖𝑛 𝑥
)(
1 𝑓𝑡 2
)
12 𝑖𝑛
13
3
(3.2808 𝑓𝑡)
3
1𝑚
)
= 1. 769
𝑓𝑡
𝑠
1 𝑓𝑡
12 𝑖𝑛
)
Darcy-Weisbach Equation
𝐿𝑒 = 2. 75(𝐼𝐷) = 2. 75 (2 𝑖𝑛) = 5. 5 𝑓𝑡
𝐿2(𝐸𝑙𝑏𝑜𝑤) = 1. 0𝐿𝑒(𝑁𝑜. 𝑝𝑐𝑠.) = 1. 0(5. 5 𝑓𝑡)(2 𝑝𝑐𝑠) = 11 𝑓𝑡
𝐿3(𝐺𝑎𝑡𝑒 𝑉𝑎𝑙𝑣𝑒) = 0. 25𝐿𝑒(𝑁𝑜. 𝑝𝑐𝑠.) = 0. 25(5. 5 𝑓𝑡)(1 𝑝𝑐) = 1. 38 𝑓𝑡
𝐿 = 𝐿1 + 𝐿2 + 𝐿3 = 24 𝑖𝑛
(
( )( )
1 𝑓𝑡
12 𝑖𝑛
) + 11 𝑓𝑡 + 1. 38 𝑓𝑡 = 14. 38 𝑓𝑡
(
2
ℎ𝑓𝑠 = 𝑓
𝐿
𝐷𝑠
𝑣𝑠
2𝑔
= 0. 02
(
2 𝑖𝑛
1 𝑓𝑡
12 𝑖𝑛
)( (
𝑓𝑡 2
𝑠
(1.769 )
14.38 𝑓𝑡
)
2 32.2
𝑓𝑡
2
𝑠
)
)
ℎ𝑓𝑠 = 0. 0838 𝑓𝑡
𝑃𝑠
𝐻𝑠 =
γ
2
+
𝑣𝑠
2𝑔
(
+ 𝑧𝑠 + ℎ𝑓𝑠 = 0 + 0 + 48 𝑖𝑛
1 𝑓𝑡
12 𝑖𝑛
) − 0. 0838 𝑓𝑡
𝐻𝑠 = 3. 9162 𝑓𝑡
TDH
𝑇𝐷𝐻 = 𝐻𝐷 − 𝐻𝑠 = 7. 002 𝑓𝑡 − 3. 9162 𝑓𝑡 = 3. 08 𝑓𝑡
Water Power
(
𝑊𝑎𝑡𝑒𝑟 𝑃𝑜𝑤𝑒𝑟 = (𝑄)(δ)(𝑇𝐷𝐻)(𝑆𝐺) = 0. 001093
𝑘𝑔
𝑠
)(9. 81 𝑘𝑁/𝑚 )(0. 9134)
𝑊𝑎𝑡𝑒𝑟 𝑃𝑜𝑤𝑒𝑟 = 0. 013 𝐻𝑃
Power Input
𝑃𝑜𝑤𝑒𝑟 𝐼𝑛𝑝𝑢𝑡 = 3𝐸𝐼𝑐𝑜𝑠(∅) = 3(220 𝑉)(8. 3 𝐴)(0. 8)
𝑃𝑜𝑤𝑒𝑟 𝐼𝑛𝑝𝑢𝑡 = 3. 39 𝐻𝑃
Motor Brake Power
η𝑚𝑜𝑡𝑜𝑟 =
𝑀𝑜𝑡𝑜𝑟 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟
𝑃𝑜𝑤𝑒𝑟 𝐼𝑛𝑝𝑢𝑡
= 0. 85 =
𝑀𝑜𝑡𝑜𝑟 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟
0.29 𝐻𝑃
𝑀𝑜𝑡𝑜𝑟 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟 = 2. 88𝐻𝑃
14
3
Pump Brake Power
𝑛𝑡 =
𝑃𝑢𝑚𝑝 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟
𝑀𝑜𝑡𝑜𝑟 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟
𝑃𝑢𝑚𝑝 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟
2.88 𝐻𝑃
= 0. 90 =
𝑃𝑢𝑚𝑝 𝐵𝑟𝑎𝑘𝑒 𝑃𝑜𝑤𝑒𝑟 = 2. 55𝐻𝑃
Pump Efficiency
𝑛𝑝𝑢𝑚𝑝 =
𝑊𝑎𝑡𝑒𝑟 𝑃𝑜𝑤𝑒𝑟
𝑃𝑢𝑚𝑝 𝐵𝑟𝑒𝑎𝑘 𝑃𝑜𝑤𝑒𝑟
𝑥100% =
0.0135 𝐻𝑃
2.55
𝑥100%
𝑛𝑝𝑢𝑚𝑝 = 0. 5291%
Overall Efficiency
𝑛𝑜𝑣𝑒𝑟𝑎𝑙𝑙 =
𝑊𝑎𝑡𝑒𝑟 𝑃𝑜𝑤𝑒𝑟
𝑃𝑜𝑤𝑒𝑟 𝐼𝑛𝑝𝑢𝑡
𝑥100% =
0.0135 𝐻𝑃
3.39 𝐻𝑃
𝑛𝑜𝑣𝑒𝑟𝑎𝑙𝑙 = 16. 21%
15
𝑥100%
TEST DATA ANALYSIS
This experiment had already received all of the necessary data. While the experiment
could not be physically carried out, data such as pump speed, current, pressure, suction water
level, and discharge capacity were given. Because the experiment only requires a basic
understanding of operating principles, this data, together with the equations provided in the
experiment instructions, made computing the missing values relatively straightforward. The only
difficult aspect of the experiment was the unit conversion, but everything else worked
swimmingly. Looking at the entire set of findings and calculations, it is evident that the pump
performed better as the suction water level increased, as seen by the greater pump and overall
efficiency. This behavior may be explained by the fact that as the suction water level increases,
the pump's vacuum, suction, and seal improve, allowing more fluid to be pushed with each turn.
As a result, the pump's performance improves.
These are the formulas used in this experiment:
Pump Discharge
𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦 (𝑣𝑜𝑙𝑢𝑚𝑒) =
𝑚𝑎𝑠𝑠
𝑑𝑒𝑛𝑠𝑖𝑡𝑦
Total Dynamic Head
𝑇𝐷𝐻 = 𝐻𝑑 − 𝐻𝑠
Dynamic Discharge Head:
𝐻𝑑 =
𝑃𝑑
δ
+
𝑉𝑑
2
2𝑔
+ 𝑍𝑑 + ℎ𝑓𝑑
Dynamic Suction Head:
𝐻𝑠 =
𝑃𝑠
δ
2
+
𝑉𝑠
2𝑔
+ 𝑍𝑠 + ℎ𝑓𝑠
Velocity of Water:
𝑉=
𝐶𝑎𝑝𝑎𝑐𝑖𝑡𝑦
𝐶𝑟𝑜𝑠𝑠−𝑠𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 𝐴𝑟𝑒𝑎
Water Power: 𝑊𝑃 = 𝑄 𝑥 δ 𝑥 𝑇𝐷𝐻 𝑥 𝑆. 𝐺
Power Input: 𝑃𝐼 = 3𝐸𝐼𝑐𝑜𝑠θ
16
Brake Horsepower:
𝐵𝑃𝑃 = 𝑛𝑚𝑛𝑡𝑃𝐼
( )𝑥 100%
=(
)𝑥 100%
Pump Efficiency: η𝑃 =
Overall Efficiency: η𝑜
𝑊𝑃
𝐵𝑃
𝑊𝑃
𝑃𝐼
17
CONCLUSION
The students were successful in meeting the experiment's objectives. For starters, they
understood the principles of rotary pump functioning. Finally, utilizing the professor's lecture and
experiment guide, they were able to figure out how to run a rotary pump. The students were
separated into three groups based on the exact settings for the belt and pulley changes, which
include low speed, medium speed, and high speed. Each member of the group was allocated to a
single trial, which makes obtaining the required numbers for the data collection much faster.
Ultimately, the crew was able to complete all of the computations and the final data sheet.
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RECOMMENDATION
19
REFERENCES
20
PRELIMINARY DATA SHEET
21
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