An Experimental Investigation of the Cold Mass Fraction, Nozzle Number, and Inlet Pressure Effects on Performance of Counter Flow Vortex Tube

This paper discusses the experimental investigation of vortex tube performance as it relates to cold mass fraction, inlet pressure, and nozzle number. The orifices have been made of the polyamide plastic material. Five different orifices, each with two, three, four, five and six nozzles, respectively, were manufactured and used during the test. The experiments have been conducted with each one of those orifices shown above, and the performance of the vortex tube has been tested with air inlet pressures varying from 150 kPa to 700 kPa with 50 kPa increments and the cold mass fractions of 0.5-0.7 with 0.02 increments. The energy separation has been investigated by use of the experimentally obtained data. The results of the experimental study have shown that the inlet pressure was the most effective parameter on heating and the cooling performance of the vortex tube. This occurs due to the higher angular velocities and angular momentum conservation inside the vortex tube. The higher the inlet pressure produces, the higher the angular velocity difference between the center flow and the peripheral flow in the tube. Furthermore, the higher velocity also means a higher frictional heat formation between the wall and the flow at the wall surface of the tube. This results in lower cold outlet temperatures and higher hot outlet temperatures

An Experimental Investigation of Performance and Exergy Analysis of a Counterflow Vortex Tube Having Various Nozzle Numbers at Different Inlet Pressures of Air, Oxygen, Nitrogen, and Argon

An experimental investigation has been carried out to determine the thermal behavior of cooling fluid as it passes through a vortex tube and the effects of the orifice nozzle number and the inlet pressure on the heating and cooling performance of the counterfiow type vortex tube (RHVT). Experiments have been performed using oxygen (O-2), nitrogen (N-2), and argon (Ar). Five orifices have been fabricated and used during the experimental study with different nozzle numbers of 2, 3, 4, 5, and 6. The orifices used at these experiments are made of the polyamide plastic material. The thermal conductivity of polyamide plastic material is 0.25 W/m K. To determine the energy separation, the inlet pressure values were adjusted from 150 kPa to 700 kPa with 50 kPa increments for each one of the orifices and each one of the studied fluids. The vortex tube that was used during the experiments has L/D ratio of 15 and the cold mass fraction was held constant at 0.5. As a result of the experimental study, it is determined that the temperature gradient between the cold and hot exits is decreased depending on the orifice nozzle number increase. Exergy analyses have been realized for each one of the studied fluids under the same inlet pressures with the experiments (P-i = 150-700). The exergy efficiency of the vortex tube is more affected by inlet pressure than nozzle number. {[}DOI: 10.1115/1.4002284

Rapid Thermal Cycling of Injection Molds: An Overview on Technical Approaches and Applications

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