E. Torrella

Experimental energetic analysis of the subcooler system in a two-stage refrigeration facility driven by a compound compressor

This paper presents a detailed experimental analysis of the energetic effects of using a subcooler system in a two-stage refrigeration facility driven by a compound compressor. The analysis is carried out by comparing the experimental performance of the two-stage cycle working with the subcooler system to the experimental performance of the two-state cycle working without the subcooler system in an evaporating temperature range between −36°C and −21°C and in a condensing temperature range between 31°C and 49°C using R-404A as the working fluid. Experimental results show that the amount of refrigerant used to obtain the subcooling, which is injected between the compression stages, causes an increment in the interstage working pressure, in power consumption, and in the cooling capacity of the cycle. This paper discusses and analyzes these modifications.

Experimental Evaluation of the Energy Performance of an Air Vortex Tube when the Inlet Parameters are Varied

The paper presents the analysis of the energy performance of an air vortex cooling tube under variations of the air inlet properties, with three independent experimental tests validated through the energy balance in the device. The experimental analysis includes the following variations of the input conditions: First, the effect of the air inlet pressure to the vortex tube, focused on the analysis of temperature variations in the output cold stream and in the cooling capacity when the cold flow fraction varies. Second, we studied air inlet temperature variations to the vortex tube under different cold flow fractions, which is an analysis not found in the literature. And finally, is studied the performance of the vortex tube when the insulation is provided or in absence of insulation.

Second-law analysis of two-stage vapour compression refrigeration plants

This paper describes a Second Law Analysis based on experimental data of a two-stage vapour compression facility driven by a compound compressor for medium and low-capacity refrigeration applications, which operates with the most usual inter-stage configurations (direct liquid injection and subcooler). The experimental analysis is performed for an evaporating temperature range between ?36°C and ?20°C and for a condensing temperature range between 30°C and 47°C using the refrigerant R-404A. The final results are compared with energy analysis from previous works. Additionally, a new criterion of equivalence between the simple vapour compression cycle and the two-stage compression cycle is given.