FM Lab 8.pdf this is pdf file data u need to know

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1. Figure I: Series/Parallel pump Apparatus
Experiment No. 08
Objective:
To investigate the performance characteristics of Centrifugal pump in series combination.
Experimental Setup:














1.Prssure Gauge 1, P1 4.Pressure Gauge 2, P2
2. Valve 1, V1 5.Valve 3, V3
3. Valve 2, V2 6. Pressure Gauge 3, P3


Theory:
1. Pump:
A pump is a machine or device that is used to force a liquid or gas to flow in a direction.
Pumps operate by some mechanism (typically reciprocating or rotary) and consume energy to
perform mechanical work moving the fluid. Pumps operate via many energy sources,
including manual operation, electricity, engines, or wind power, come in many sizes, from
microscopic for use in medical applications to large industrial pumps.

2. Figure II: Classification of pumps
2. Classification of Pump:
Pumps are divided into 2 major categories:
 Dynamic
 Positive Displacement

























2.1. Dynamics Pumps:
2.1.1. Centrifugal Pump:
Centrifugal pumps use an impeller, which has curved blades that accelerate
fluids towards their edge when rotating. The impeller is normally driven by an electric
motor or combustion engine, and its movement produces suction at the pump inlet,
drawing water inside.
Based on the flow they produce; centrifugal pumps can be classified into three
subtypes. The flow pattern is determined by both the impeller shape and the pump’s
construction

3. Figure III: Centrifugal pump Operating curve


Subtypes Description Performance
Axial Flow Produces flow along the same direction as the impeller
shaft and is also known as propeller pump.
High flow rate
Low pressure
Radial Flow Produces flow perpendicular to shaft (90° angle). Low flow rate
High pressure
Mixed Flow Combines radial and axial flow, producing a conical
flow pattern around the impeller shaft.
Medium flow rate
Medium pressure
2.2.
Positive displacement pumps
:
Positive displacement pumps move a fixed amount of fluid at regular intervals. They
are built with internal cavities that fill up at the suction side, to be discharged with higher
pressure at the outlet. Based on how the fluid is displaced, positive displacement pumps
can be reciprocating or rotary.
Subtypes Description Performance
Reciprocating Flow is established by a cavity that expands and contracts,
such as a piston. Water moves into the cavity during
expansion, and is forced out during contraction, while flow
direction is controlled with check valves.
Bladder
Diaphragm
Peristaltic
Piston
Rotary Uses a rotor that traps water in cavities, releasing it at the
pump outlet. These cavities can be the spaces between gear
teeth or screw threads, among other configurations. Some
designs use more than one shaft, but the principle is the same:
the rotor shape is designed to capture “pockets” of water and
displace them in the intended direction.
Gear
Screw
cavity
Rotary lobe
Rotary vane
3. Centrifugal Pump System:
A centrifugal pump will pump fluid at the point where the system curve intersects the pump
curve.

4. Figure IV: Operation curve of single and series pumps

Figure V: Demonstration of series pump
3.1. Series Operation:
Centrifugal pumps are connected in series if the discharge of one pump is connected
to the suction side of a second pump. Two similar pumps, in series, operate in the
same manner as a two-stage centrifugal pump. Each of the pumps is putting energy
into the pumping fluid, so the resultant head is the sum of the individual heads.
Some things to consider when you connect pumps in series:
 Both pumps must have the same width impeller or the difference in capacities (GPM
or Cubic meters/hour.) could cause a cavitation problem if the first pump cannot
supply enough liquid to the second pump.
 Both pumps must run at the same speed (same reason).
 Be sure the casing of the second pump is strong enough to resist the higher pressure.
Higher strength material, ribbing, or extra bolting may be required.
 The stuffing box of the second pump will see the discharge pressure of the first pump.
You may need a high-pressure mechanical seal.
 Be sure both pumps are filled with liquid during start-up and operation.
 Start the second pump after the first pump is running.















3.2. Demonstration of Pump in series:

3.3. Advantage of series pumps:
 Centrifugal pumps in series are used to overcome larger system head loss than one
pump can handle alone.

5.  Used for high head at the same flow rate.
Experimental Procedure:
1. Set the pump demonstrator for series operation.
2. To Set pumps in series fully open the valve 2 (V2) fully and close Valve 1 & 3
(V1&V3).
3. Turn on pump 1 and pump 2.
4. Measure the inlet pressure p1, the pump outlet pressure p2 and p3 and the volume
flow V.
5. Reduce the volume flow a bit by gradually closing valve 5 (V5) and take the
measurements according to point 4.
6. Repeat steps 4 and 5 until the volume flow is completely throttled.
Observations and Calculations:
Sr.#
Flowrate
(LPM)
P1
(gauge)
(N/m
2
)

P2
(gauge)
(N/m
2
)

P3
(gauge)
(N/m
2
)

RPM
Q
(m
3
/Sec)
Pump
Head
(m)
Power
Fluid
(W)
Power
Electric
(W)
%
Efficiency





Specimen Calculation:

6. Graphs:

7. Conclusion:

8. Rubrics
CLO_2: Analyze the acquired experimental data to investigate its relationship theoretically
in pumps and turbines.
Criteria Excellent (4) Good (3) Fair (2) Poor (1) score
Technical
Soundness /
performance
Instruments
and tools are
used
appropriately
and effectively
Instruments and
tools are mostly
used
appropriately
Some misuse or
inefficiency in
instrument usage
Instruments or
tools are
misused or
ineffective

Data
Collection
and
Presentation
Data is
comprehensive,
relevant, and
accurately
recorded. Data
is effectively
presented using
appropriate
tables, graphs,
and visuals
Data is mostly
comprehensive,
relevant, and
accurately
recorded. Data is
mostly
effectively
presented
Data is somewhat
comprehensive
and relevant. Data
presentation is
adequate
Data is
incomplete,
irrelevant, or
inaccurately
recorded. Data
presentation
lacks clarity or
coherence

Data
Analysis
Analysis
demonstrates
deep
understanding
of the data and
addresses all
relevant
aspects.
Conclusions
drawn are
logical, well
supported, and
aligned with
data
Analysis
demonstrates
understanding of
the data and
addresses most
relevant aspects.
Conclusions
drawn are
mostly logical
and supported
Analysis addresses
some relevant
aspects.
Conclusions are
somewhat
supported and
logical
Analysis lacks
depth or
relevance.
Conclusions
are illogical or
not supported
by data


Scoring Guide:
 4: Excellent - Exceeds expectations; demonstrates exceptional proficiency and
mastery.
 3: Good - Meets expectations; demonstrates solid understanding and competency.
 2: Fair - Partially meets expectations; some areas need improvement or refinement.
 1: Poor - Does not meet expectations; significant deficiencies or lack of
understanding.