Experiments

  • Production of heat pump performance curves based on the R134a properties at a variety of evaporating and condensation temperatures.
  • The effect of compressor pressure ratio on volumetric efficiency.
  • Determination of power Input, heat output and coefficient of performance.
  • Heat pump performance curves over a range of source and delivery temperatures.
  • Determination of energy balances for the condenser and compressor.
  • Production of the vapor compression cycle on a p-h diagram and comparison with the ideal cycle

 

Specification

Compressor
Type: Hermetic
Refrigerant: R-134a
Condenser
Type: Plate Heat Exchanger
Medium : Water
Evaporator
Type: Fan Cooled Continuous Tubing and External Finned
Pressure Safety Switch
Delivery Side
Suction Side
Suction side (low pressure Gauge)
Pressure: -1~16bar
Delivery side (high pressure Gauge)
Pressure: -1~25bar

The Mechanical Heat Pump is aimed for education use and produces data in both quantitative and qualitative forms that are simple for students to understand. Students may make measurements and make calculations thanks to the equipment’s compact and appropriate instrumentation. The experiment’s goal is to illustrate how heat can be transferred from a colder object to a hotter object, which is one of refrigeration’s fundamental concepts. A typical compressor condenser unit, a watt meters, and control instrumentation comprising a flowmeter, thermocouples, and pressure gauges are all included. All of the parts and instruments for the Mechanical Heat Pump Apparatus are fixed on the stable platform, making it a stand-alone unit. A thermostatic expansion valve, a water-cooled plate heat exchanger, a hermetic compressor, and an air heated evaporator make up the heat pump. The components are arranged in a similar way to how they are in many household air-water heat pumps, where they can be seen from the front of the unit. A little bit superheated refrigerant (R-134a) vapour enters the compressor from the evaporator during operation, increasing its pressure. Due to the increase in temperature, heated vapour then enters the water-cooled condenser. The refrigerant loses heat to the cooling water and turns into liquid before it reaches the expansion valve. The pressure of the liquid refrigerant decreases as it passes through the expansion valve. The saturation temperature subsequently drops below the ambient temperature as a result of this. As a result, the refrigerant and the air being drawn over the coils are at different temperatures as they pass through the evaporator. The refrigerant begins to boil as a result of the heat transfer, and when it leaves the evaporator, it is a slightly superheated vapor and is ready to go back to the compressor. The water flow rate and the water’s inlet temperature regulate the temperature at which heat is delivered in the condenser. Environmental conditions play a significant role in determining evaporation temperature. There are instruments available for measuring the flow rates of cooling water and refrigerant, the power input to the compressor, and all relevant temperatures.