Fast heat transfer calculations in supercritical fluids versus hydrodynamic approach.
نویسندگان
چکیده
This study investigates the heat transfer in a simple pure fluid whose temperature is slightly above its critical temperature. We propose an efficient numerical method to predict the heat transfer in such fluids when the gravity can be neglected. The method, based on a simplified thermodynamic approach, is compared with direct numerical simulations of the Navier-Stokes and energy equations performed for CO2 and SF6. A realistic equation of state is used to describe both fluids. The proposed method agrees with the full hydrodynamic solution and provides a huge gain in computation time. The connection between the purely thermodynamic and hydrodynamic descriptions is also discussed.
منابع مشابه
Numerical Predictions of Turbulent Mixed Convection Heat Transfer to Supercritical Fluids Using Various Low Reynolds Number k-e Turbulence Models
There are a number of systems in which supercritical cryogenic fluids are used as coolants or propellant fluids. In some modern military aircraft, the fuel is pressurized above its critical point and used as a coolant to remove heat from the aircraft engine. Accurate prediction of heat transfer coefficients to turbulent flows of supercritical fluids is essential in design of such systems. One o...
متن کاملConvection Heat Transfer Modeling of Nano- fluid Tio2 Using Different Viscosity Theories
In this paper, the effects of adding nanoparticles including Tio2 to a fluid media for purpose of free convection heat transfer improvement were analyzed. The free convection was assumed to be in laminar flow regime and the solutions and calculations were all done by the integral method. Water, as a Newtonian fluid, was considered the base fluid (water) and all the thermo physical properties of...
متن کاملNumerical simulation of nanofluids flow and heat transfer through isosceles triangular channels
Nanofluids are stable suspensions of nanoparticles in conventional heat transfer fluids (base fluids) that exhibit better thermal characteristics compared to those of the base fluids. It is important to clarify various aspects of nanofluids behavior. In order to identify the thermal and hydrodynamic behavior of nanofluids flowing through non-circular ducts, in the present study the laminar flow...
متن کاملSlip Velocity in Flow and Heat Transfer of Non-newtonian Fluids in Microchannels
The steady-state fully-developed laminar flow of non-Newtonian power-law fluids is examined in a circular microchannel with slip boundary condition and under an imposed constant wall heat flux. Effects of slip as well as the hydrodynamic and thermal key parameters on heat transfer and entropy generation are investigated. The results reveal that increasing the Brinkman number and the flow behavi...
متن کاملSimulation of Heat and Mass Transfer of a Co2 Binary Mixture, in the Miscible Conditions of a Supercritical Antisolvent Process
A complete description of the Supercritical Antisolvent Process requires the modelling of several complex physical phenomena such as heat and mass transfer, hydrodynamic, phase equilibria of ternary mixtures, and nucleation /growth of the specie to be precipitated; moreover, the description should also account for the biphasic case, where the jet of organic solvent breaks up as droplets. As a f...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Physical review. E, Statistical, nonlinear, and soft matter physics
دوره 67 6 Pt 1 شماره
صفحات -
تاریخ انتشار 2003