performed wellbore-reservoir coupled five-spot model and pointed out that the specific enthalpy change of C[O.sub.2] in the wellbore is so small relative to its intrinsic specific enthalpy that the wellbore flow can be regarded as isenthalpic process
, and the temperature of the fluids in production well will decrease rapidly with pressure.
* The expansion valve undergoes an isenthalpic process
The system model contains a compressor model, an accumulator model, and microchannel heat exchanger models, while the expansion valve was modeled by a simple isenthalpic process, and subcooling at condenser exit was arbitrarily set as an input.
Expansion valves are modeled by isenthalpic processes. System performance is calculated by connecting all parts in the same way as the physical system and solved iteratively.
Table 1 shows that steam pressure reduction through a PRV from 140 psig (965 kPa) to 20 psig (138 kPa) is an isenthalpic process
that maintains a constant enthalpy through the pressure reduction.
Assuming an isenthalpic process
, the R-134a will exit the expansion valve as a two-phase liquid-vapor mixture at state 4 in Figure 4.
The refrigerant temperature at the inlet of the test section was calculated by considering isenthalpic process
in expansion device.
The throttling expansion is an isenthalpic process