DEVELOPMENT OF FUNDAMENTAL EQUATION OF STATE FOR THERMODYNAMIC PROPERTIES OF R-1234ZE(E) AND R-1233ZD(E) WITH SIMULTANEOUS OPTIMIZATION

• Main Author: Budiarso, Galih
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/47411
• Institution: Institut Teknologi Bandung

The air conditioning system is a need with a relatively high priority scale at this time. The increasing demand for air conditioning systems has led to environmental issues such as global warming and depletion of the ozone layer. Application of refrigerants from the Hydro Floro Olefins (HFO) group, namely R-1234ze(E) and R-1233zd(E), in air conditioning system products is the solution to the issue because it is environmentally friendly. Air conditioning system products that implement both types of refrigerants must be designed by conducting energy analysis to obtain optimal performance. The equation of state for thermodynamics properties plays an important role in conducting energy analysis, because all thermodynamic properties can be predicted by this equation. Therefore, this study aims to obtain the equation of state for thermodynamic properties of refrigerant R-1234ze(E) and R-1233zd(E), which has good accuracy and has good extrapolation ability, considering that both types of refrigerants are new refrigerants and have great potential to be applied. The equation of state for thermodynamic properties of R-1234ze(E) and R-1233zd(E) developed in this study is based on the Helmholtz equation. This equation is used because it can predict all thermodynamic properties explicitly over a wide range. Optimization in the development of this equation use the genetic algorithm method which is combined with the least squares regression, and is carried out simultaneously. A simultaneous process is carried out so that the process of developing equations for R-1234ze(E) and R-1233zd(E) can be carried out simultaneously. The simultaneous optimization process reduces the time taken and the equation obtained has the same structure. The results obtained from this study consisted of 3 ancillary equations and 1 Helmholtz equation with the same structure for R-1234ze(E) and R-1233zd(E) refrigerants. All equations obtained have good accuracy indicated by average absolute deviation with small values. The ancillary equations of R-1234ze(E) have an average absolute deviation of 0.096%, 0.114% and 1.004% for the saturated pressure, saturated liquid density, and saturated vapor density properties respectively, while the ancillary equations of R-1233zd(E) have an average absolute deviation of 1.106%, 0.112%, and 3.509%. The result of the ideal gas isobaric heat capacity equation development of R-1234ze(E) and R-1233zd(E) has an average absolute deviation of 0.057% and 0.166% respectively. The R-1234ze(E) Helmholtz equation has an average absolute deviation of 0.084% and 0.395% for the liquid and vapor density properties, while for R-1233zd(E) is 0.116% and 1.988%. The average absolute deviation of saturated pressure, saturated liquid density, and saturated vapor density properties of the R-1234ze(E) Helmholtz equation is 0.102%, 0.570%, and 1.820%, while for R-1233zd(E) is 1.432%, 0.160%, and 4.079%. The R-1234ze(E) Helmholtz equation for isochoric, isobaric, and saturated heat capacity properties has an average absolute deviation of 12.951%, 1.726%, and 5.440%. Whereas the R-1233zd(E) Helmholtz equation has an average absolute deviation of 3.622% for the isobaric heat capacity property. The R-1234ze(E) Helmholtz equation has an average absolute deviation of 0.710% and 0.063% for the speed of sound properties of liquid and vapor phases, while for the R-1233zd(E) Helmholtz equation is 0.147% and 0.176%. The equation also has a good extrapolation ability, indicated by the achievement of test parameters used, but it is recommended that up to a temperature of 600 K and a pressure of 100 MPa.