Then, use a thermometer to measure the temperature of the refrigerant tank outer surface and connect a pressure gauge to the pressure tank to measure the internal pressure. Find the saturation pressure corresponding to the measured outer surface temperature from Table 19-4. If the deviation between...
It is a pure refrigerant with an ODP equal to zero and a GWP lower than that of R22 (GWPR22=1700; GWPR134a=1300), as presented in Table 1 [1], [2]. Its saturation pressures are 40% less than those of R22. Although replacement of R12 by R134a for refrigeration has been widely ...
The first one is the test loop using R134a refrigerant while the second is an auxiliary cooling loop using R404a. Fig. 1 shows a schematic diagram of the test loop including a close-up photograph of the test section part. It consists of R134a tank, a gear pump, a sub-cooler, two ...
Table 3 lists the experimental datasets, subdivided by refrigerant and saturation temperature. It also highlights the maximum and minimum values reached in each set of: saturation temperature, saturation pressure, specific mass flow rate, heat flux, and average vapor quality- evaluated as the average...
However, in the case of saturation adsorption, the desorption heat of R32 was lower than that of R1234yf and R1234ze(z). The addition of MOF-74 nanoparticles (NPs) could enhance the energy storage capacity of the pure refrigerant; besides, R1234yf and R1234ze(z) nanofluids had superior...
Namely, superheat is the temperature increase of vapor refrigerant above its saturation point. It is defined as the temperature difference between: Temperature of refrigerant vapor when it exits in the evaporator coil (when we have 100% vapor, the temperature of vapor will increase). Temperature of...
The facility provides relatively efficient experiments but more importantly, the vapor quality of refrigerant is changed continually in one pass. The flow in the channels is closer to a realistic heat exchanger in a vapor-compression system, especially for refrigerant-oil mixtures or refrigerant blends...
The pre-heater (4) and the heat exchanger (6) are used to heat the refrigerant liquid close to the saturation state. Then, the Experimental results and discussion for smooth and microfin tubes Experimental data of void fraction for both smooth and microfin tubes were obtained for the range ...
In addition, they use HFC refrigerant. Characteristics of HCFC, HFC refrigerants, and HFO refrigerants are summarized in Table 1. HFO refrigerants R1234yf and R1234ze(E) have the same ODP (Ozone depletion potential) as R134a. Their GWPs (Global Warming Potentials) are also very low. In ...
To further investigate the impact of thermal effects on the cavitation process within the prototype, the numerical simulation modifies the saturation pressure of the refrigerant from a non-isothermal model, represented by a polynomial function of temperature, to an isothermal model. Table 3. Comparison...