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Purpose. Measure Flow rate in a pipe (smooth)Friction factorVelocity profileSpecify the turbulent-flow Reynolds NumberCompare the results with benchmark dataUncertainty analysis for:Friction factorVelocity profile. Test Design. The facility consists of:Closed pipe networkFanReservoir I
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1. Measurement of flow rate, friction Factor, and velocity Profile in Pipe Flow 57:020 mechanics of Fluids and Transfer Processes
Experimental Laboratory #2
2. Purpose Measure
Flow rate in a pipe (smooth)
Friction factor
Velocity profile
Specify the turbulent-flow Reynolds Number
Compare the results with benchmark data
Uncertainty analysis for:
Friction factor
Velocity profile
3. Test Design The facility consists of:
Closed pipe network
Fan
Reservoir
Instruments used:
3 Venturi meters
Simple water Manometer
Differential Water manometer
Pitot Probe
Digital Micrometer (Accurate radial positioning)
4. Air Flow Pipe facility
5. Test Design (Continue)
6. Pressure tap manifold and Pitot-tube housing Pressure tap manifold
Pitot-tube housing
7. Measurement Systems: The equipment used in the experiment includes:
Digital thermometer with a range of 40 to 450 ?F and a smallest reading of 0.1 ?F for measurement of the environment temperature.
Digital micrometer with least significant digit 0.01 mm for positioning the Pitot-tube inside the pipe.
Simple water manometer with a range of 2.5 ft and a least scale division of 0.001 ft for measurement of the head at each pressure tap along the pipes and for measurement of velocities using the Pitot-tube arrangement .
Differential water manometer with a range 3 ft and a least scale division of 0.001ft for measurement of the head drop across the Venturi meters.
8. Measurement Systems (continue) For the flow rate and friction factor, the individual measurement are performed for:
Ambient air temperature (A.3)
Pipe air temperature (A.5)
Pipe pressure head
Venturi meter pressure head drop
The experimental Results are:
Manometer water density
Air density
Kinematic viscosity
Flow rate
Reynolds number
Friction factor
Data reduction equations are:
9. Measurement Systems (continue) For the velocity profile, the individual measurement systems are for:
the ambient temperature
pipe air temperature
pitot stagnation and static pressure heads.
The experimental results are for:
manometer water density (A.3)
Air density (A.5)
Velocity profile (below)
Data reduction equation: (using the Bernoulli equation along the manometer equation)
10. Flow rate, Friction factor and velocity profile measurement systems Block diagram of the experimental determination of the Friction Block diagram of the Velocity measurement
11. Data Acquisition and reduction The procedures for data acquisition and reduction are described as follow:
Use the appropriate Venturi meter, (2 smooth pipe) measure the head drop
Take reading for ambient air (manometer water) and pipe air temperatures.
To obtain velocity data, measure in the appropriate Pitot-tube box, the ambient head and stagnation heads across the full diameter. Measure the stagnation heads at radial intervals. The recommended radial spacing for one half of the diameter is 0, 5, 10, 15, 20, 23, and 24 mm.
Maintaining the discharge, measure the head along the pipe by means of the simple water manometer connected to the pressure taps located along the pipe being studied (10 times for uncertainty analysis)
Repeat step 2
Execute data reduction for data analysis and uncertainty analysis using equation above
12. Uncertainty Analysis The data reduction equation for the friction factor is:
However here we will only consider bias limits for ZSM i and ZSM j . The total uncertainty for the friction is:
The Bias Limit, Bf and the precision limit, Pf, for the result are given by:
13. Uncertainty Analysis (continue) Data Reduction equation for the velocity profile is as follow:
14. Moody Chart for pipe friction with smooth and rough walls