THERMODYNAMIC ANALYSES
Description of Analyses
1-2: Refrigerant will be compressed in this process adiabatically through the compressor, which will cause the mix to turn into a saturated vapor. This is where work is done on the system, thus the temperature will rise from Tc to Th and the pressure will increase.
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2-3: Refrigerant will pass through the condenser, and the phase of the refrigerant will go from saturated vapor to a saturated liquid. In this process, temperature and pressure will be constant.
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3-4: The refrigerant will pass through and push the expansion valve, expanding adiabatically. Temperature and pressure will decrease, with the temperature returning to Tc. This is where work is done by the refrigerant.
4-1: The refrigerant will enter the evaporator as a liquid-vapor mix and will evaporate into vapor. The temperature and pressure are constant in this process.
Chiller Plant Component Diagram
Calculations
Compressor Power 
Mass flow rate * W12 = 203.561 kW 
From datasheets:  Capacity * CW Pump kW/ton = 4798*0.08 = 223.84 kW
This value seems high as typically the coefficients of performance for water chiller systems are around 6.0. Although, the high value may partially be explained by the fact that our calculations are very theoretical assume an ideal model that disregards friction, losses or gains in heat to the surrounding because of limitations of insulation material, and the assumption of perfectly isobaric phases in the cooling process.
Additionally, in our calculations, we relied on state current temperatures and pressures from the data sheets, while implying the values of other temperatures under the assumption that no heat or energy was lost to the surroundings and that the processes were ideal. This is very important to consider when addressing our results since we assumed completely ideal situations, especially without accounting for energy loss. With the chiller plant being as massive as it is, there is a lot of fluid friction and energy effects from piping that we did not consider in our calculations. Along with this, we used instantaneous temperatures from the provided datasheets for all of the state points, when realistically, average values for the pressures and temperatures could render better results. It's imperative to consider the model of the chillers and how long they have been performing for, since they are no longer brand new and most likely no longer operating at their peak efficiencies. It would be interesting to survey the plant after the components have been recently serviced or replaced. All in all, our calculated compressor power is slightly lower than the actual data from the plant because we calculated an ideal process using assumptions.
Since the Cooling Capacities in both the manufacturer’s specs and our calculations based on real life data collected from the chiller plant have only about an 11% difference, it is safe to assume that both values are realistic since the manufacturer’s rating can only be perfectly achieved under the optimal running conditions and perhaps only when the chiller is near band new or recently serviced.
