Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.
Cyclone separators are widely used in automotive
applications, for the cleaning of hot oil mist. Most of the
available studies are dealing with the cyclone collection
efficiency, and the corresponding pressure drop. The aim of this
experimental study is to investigate the gas-to-wall heat
transfer, for a flow in a constant wall temperature cyclone
configuration, to derive an average Nusselt number correlation.
The cyclone is placed in a cold jacket, where the temperature is
imposed by external circulation of a coolant. The simultaneous
measurements of mass flow rate and characteristic temperatures
(cyclone inlet, cold wall and cyclone outlet temperatures)
permit the determination of the average wall heat transfer
coefficient, through an enthalpy balance. Static pressure
measurements at the inlet and outlet of the cyclone are used to
evaluate the pressure drop in the cyclone, and a comparison
between these results and those obtained by application of the
currently available models. The inlet Reynolds number and
geometry of the cyclone are varied. An average Nusselt number
correlation is proposed for heat transfer in a cyclone under
constant wall temperature conditions, as a function of the inlet
Reynolds number Rei (400 Rei 20 000), and for different
values of the dimensionless geometrical parameters L* (0.75
L* 2.5).
