Compressible Flow Unit
26 พฤษภาคม 2566
ผู้ชม 488 ผู้ชม
DESCRIPTION
The C1-MKIII Compressible Flow Unit has been developed jointly between Armfield Ltd and an experienced lecturer in mechanical engineering of Reading College of Technology.
The unit serves to introduce users to all the basic concepts of compressible flow through a number of experimental procedures with a variety of interchangeable clear acrylic test sections.
Project work: Students may devise additional experiments using the equipment as a project work exercise. Examples are provided
The C1-MkIII equipment comprises a single-stage air compressor, complete with a test section and a throttling valve, plus an electronics console containing the necessary controls and instrumentation.
The single-stage compressor is driven by an integral three-phase AC motor. The compressor speed can be varied using an advanced torque-vector frequency inverter, which gives stable and accurate speed control plus direct electronic read-out of the torque produced by the motor.
The compressor is fitted with an outlet duct incorporating a throttling valve, which allows the flow to be varied independent from compressor speed.
The equipment is supplied with a convergent-divergent test section, fitted at the compressor inlet, designed to produce Mach-1 velocity at the throat. The duct is fabricated from clear acrylic, enabling the student to see the construction and the profiles. A pressure-sensing ring tapping is provided at the inlet, at the throat and at the discharge end of the diffuser. This duct allows all the major concepts of compressible flow to be demonstrated.
The electronics console includes two high-range and two low-range differential pressure sensors plus a control for motor speed and displays for the compressor speed, the pressures and the motor torque.
EXPERIMENTAL CONTENT
- Demonstrate the phenomenon of ‘choking’ in a convergent/divergent duct
- Investigate the validity of the isentropic flow equations for compressible flow in a convergent duct
- Demonstrate the effect of compressibility on flow equations for a convergent duct
- To deduce a value of Specific Heat Ratio (γ) for air using the equation for isentropic flow in a convergent duct
- Investigate pressure recovery along a divergent duct by measuring duct efficiency
- Investigate the relation between friction loss & velocity for incompressible flow and to find an approximate value for the friction coefficient
- To investigate the relation between the friction coefficient and the Reynolds number for a given pipe
- Determine the friction coefficient for a case of compressible flow
- Investigate the relation between the pressure recovery across a sudden enlargement and, upstream flow velocity, assuming incompressible flow
- To determine the Coefficient of Discharge
- Investigate the validity of the formula for the pressure rise across a sudden enlargement for compressible flow
- To investigate, for incompressible flow, the relation between the flow rate through, and the pressure drop across, a pipeline orifice.
- To determine the relationship between the coefficient of discharge and the ratio n for the pipeline orifice
- Investigate the effects of compressibility on discharge coefficients
- To investigate the variation of pressure rise, power input and isothermal efficiencies of a centrifugal compressor with mass flow rate at constant speed
- Produce a performance characteristic using mass flow rate and pressure rise as parameters, with contours of constant speed and constant efficiency
- Account for the energy provided by the compressor driving motor
- To investigate the relationship between fluid velocity and pressure drop (head loss) along a 90° smooth bend
- Investigate whether the pressure varies radially across a bend
FEATURES
- Variable-speed air compressor with accurate electronic speed control
- Electronic pressure sensors
- Standard unit includes convergent-divergent duct designed to produce Mach 1 velocity at the throat
- Data logging option available