Simple Compression Refrigeration Circuit for Education

Sci-tech Vapour Compression Refrigeration Air-Conditioning Trainer Model RAC 023 is an invaluable aid in the effective understanding of the air-conditioning process. The equipment is a comprehensive plant, which incorporates an axial flow fan, damper and test duct sections, flow meter, electronic control panel and loading arrangement. Temperature sensors at various points facilitate psychometric studies.

System Components

·       Compressor; Hermetically sealed rotary compressor; Power @ 500W

·       Refrigerant Type R134a or R1234yf (environmentally friendly)

·       Evaporator Type: Finned-tube air heat exchanger with fan

·       Condenser Type: Finned-tube air-cooled condenser with axial fan

·       Expansion Device: Capillary tube or thermostatic expansion valve (TEV)

·       Evaporator Air Flow: ~100 – 300 m³/h with adjustable speed fan

·       Condenser Air Flow: ~100 – 300 m³/h with adjustable speed fan

·       Working Pressure Range: 1 to 12 bar (depending on refrigerant)

·       Temperature Range: -5°C to 50°C air temperature

·       Instrumentation (11: Touch Screen Display):

- Pressure sensors (P) at key points (evaporator inlet/outlet, condenser inlet/outlet)

- Temperature sensors (T) at same points

- Refrigerant flowrate sensor (optional)

- Airflow velocity sensor (optional)

- Power meter (compressor electrical input)

- Energy consumption (kWh counter)

- Date and time display

·       Control Interface: Basic digital control (ON/OFF, fault reset, fan speed control)

·       ‘Sci-Cal’ computer interface & DAQ with ‘LabView Data Logging (Optional)

·       Safety Features: High/low pressure cutouts, overheat protection, electrical fuse, refrigerant sight glass

·       Frame/Structure: Aluminum profile or powder-coated steel frame with Casters

·       Transparent acrylic guards for visibility

Optional

Ø  Computerised AC trainer

Experiments

¨     Study of a typical air-conditioning cycle

¨     Humidification and dehumidification

¨     Heat balance at evaporator, condenser and the overall system

¨     Compressor efficiency at various loads

¨     Psychometric charts

¨     Determination of coefficient of performance

¨     Re-circulation of air