Open AccessInfluence of geometric and operating parameters on the flow behavior of the helical capillary tube
Author(s) -
Pravin Jadhav,
Neeraj Agrawal
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1451/1/012004
Subject(s) - mechanics , capillary action , refrigerant , materials science , transcritical cycle , tube (container) , evaporator , thermodynamics , mass flow rate , adiabatic process , flow (mathematics) , mass flow , volumetric flow rate , gas compressor , chemistry , composite material , physics
This paper reveals numerical study on an adiabatic helical capillary tube employing homogenous and unchoked flow conditions for a CO 2 refrigerant. The numerical model is based on the basic principles of conservation of mass, momentum, and energy. A result of the present model is validated with previously published test results. Thermodynamic and transport properties of CO 2 refrigerant are obtained from property code CO2PROP which is developed by employing an iterative procedure of derivatives of Helmholtz free energy function. The influence of various geometric parameters like tube diameter, roughness, and coil diameter on the mass flow rate of the capillary tube has been evaluated. The mass flow of the helical capillary tube largely depends on the internal diameter. While the very minor change in mass is observed with change surface roughness. Influence of various operating factors like gas cooler pressure, temperature and evaporator temperature evaluated. A significant change in mass is observed with the change in gas cooler temperature, comparatively less effect is observed with evaporator temperature. For optimum performance of the transcritical CO 2 cycle, selection of proper gas cooler temperature, gas cooler pressure is a key factor. This study may be useful for the design of helical capillary tube for CO 2.