FMM3701 Practical Answers Year 2024
Comprehensive Guide to Practical Experiment Procedures &
Calculations
EXAM INSTRUCTIONS
Course: FMM3701 – Fluid Mechanics and Turbomachines
Institution: University of South Africa (UNISA)
Year: 2024
Format: Practical Experiments & Theoretical Calculations
Content Areas: Turbine Performance Testing, Fluid Flow Calculations, Bernoulli's
Theorem, Continuity Equation, Isentropic Processes
SECTION 1: TURBINE PERFORMANCE PRACTICAL PROCEDURE
Experimental Procedure for Turbine Performance Analysis
This procedure details the steps undertaken to set up the equipment, conduct the
primary test, and perform the racing characteristics test for a turbine system. The system
involved a pump drawing water from a storage tank, discharging it through a flow
sensor to a turbine inlet pipe. The turbine converted water pressure head into
mechanical energy before discharging water back to the storage tank, with the
generated energy being absorbed by a spring balance .
1.1 Equipment Set-up
1. The storage tank was filled with water, ensuring the level reached approximately 5 cm
below its full capacity .
, 2. Subsequently, the flow control valve (V1), the guide valve (TV), and the cooling water
inlet valve (V2) were all fully closed .
3. A check of the dynamometer mechanism was performed to confirm that no load was
attached, which was achieved by loosening the adjusting screw. The diameter of the
brake drum was then recorded .
4. To disengage the generator from the turbine, the clutch switch was turned to the "OFF"
position, effectively disconnecting the electric clutch .
5. Following these mechanical preparations, the ELCB, CB, and the main power switch on
the control box were activated .
6. A crucial verification step was then carried out to ensure that all initial readings for flow
rate, turbine inlet pressure, turbine speed, spring force or torque (if applicable), and
generator power or voltage and current registered zero .
1.2 Begin the Test
1. The pump motor switch was turned "ON," and the flow control valve (V1) was slowly
opened to its full extent to achieve maximum pump delivery .
2. Concurrently, the cooling water control valve (V2) was gradually opened to allow only a
minimal flow of water to the dynamometer .
3. The flow control valve (V1) was then carefully adjusted to attain a specific turbine inlet
pressure, for example, 2.2 kg/cm² .
4. At this point, the following data were meticulously recorded :
o Turbine inlet pressure, p (kg/cm²)
o Flow rate, Q (l/min)
o Turbine speed, n (rpm)
o Force, F (kg) or Power, W (optional)
5. The brake was slowly applied to achieve a spring balance force of approximately 0.4 kg,
and the aforementioned data were recorded again .
6. This process was repeated by incrementally increasing the spring balance force in steps
of about 0.2 kg until the turbine speed was reduced to approximately 700 rpm .
7. The load was removed by loosening the load adjusting screw. The nozzle pressure was
then increased by slightly closing the flow control valve (V1) to attain new desired
pressures, such as 1.4 kg/cm² or 1.6 kg/cm². The steps involving the application of the
brake and subsequent data recording were reiterated for these newly established
pressure settings .
Comprehensive Guide to Practical Experiment Procedures &
Calculations
EXAM INSTRUCTIONS
Course: FMM3701 – Fluid Mechanics and Turbomachines
Institution: University of South Africa (UNISA)
Year: 2024
Format: Practical Experiments & Theoretical Calculations
Content Areas: Turbine Performance Testing, Fluid Flow Calculations, Bernoulli's
Theorem, Continuity Equation, Isentropic Processes
SECTION 1: TURBINE PERFORMANCE PRACTICAL PROCEDURE
Experimental Procedure for Turbine Performance Analysis
This procedure details the steps undertaken to set up the equipment, conduct the
primary test, and perform the racing characteristics test for a turbine system. The system
involved a pump drawing water from a storage tank, discharging it through a flow
sensor to a turbine inlet pipe. The turbine converted water pressure head into
mechanical energy before discharging water back to the storage tank, with the
generated energy being absorbed by a spring balance .
1.1 Equipment Set-up
1. The storage tank was filled with water, ensuring the level reached approximately 5 cm
below its full capacity .
, 2. Subsequently, the flow control valve (V1), the guide valve (TV), and the cooling water
inlet valve (V2) were all fully closed .
3. A check of the dynamometer mechanism was performed to confirm that no load was
attached, which was achieved by loosening the adjusting screw. The diameter of the
brake drum was then recorded .
4. To disengage the generator from the turbine, the clutch switch was turned to the "OFF"
position, effectively disconnecting the electric clutch .
5. Following these mechanical preparations, the ELCB, CB, and the main power switch on
the control box were activated .
6. A crucial verification step was then carried out to ensure that all initial readings for flow
rate, turbine inlet pressure, turbine speed, spring force or torque (if applicable), and
generator power or voltage and current registered zero .
1.2 Begin the Test
1. The pump motor switch was turned "ON," and the flow control valve (V1) was slowly
opened to its full extent to achieve maximum pump delivery .
2. Concurrently, the cooling water control valve (V2) was gradually opened to allow only a
minimal flow of water to the dynamometer .
3. The flow control valve (V1) was then carefully adjusted to attain a specific turbine inlet
pressure, for example, 2.2 kg/cm² .
4. At this point, the following data were meticulously recorded :
o Turbine inlet pressure, p (kg/cm²)
o Flow rate, Q (l/min)
o Turbine speed, n (rpm)
o Force, F (kg) or Power, W (optional)
5. The brake was slowly applied to achieve a spring balance force of approximately 0.4 kg,
and the aforementioned data were recorded again .
6. This process was repeated by incrementally increasing the spring balance force in steps
of about 0.2 kg until the turbine speed was reduced to approximately 700 rpm .
7. The load was removed by loosening the load adjusting screw. The nozzle pressure was
then increased by slightly closing the flow control valve (V1) to attain new desired
pressures, such as 1.4 kg/cm² or 1.6 kg/cm². The steps involving the application of the
brake and subsequent data recording were reiterated for these newly established
pressure settings .
