抄録
This paper describes a detailed experimental investigation of heat transfer in a reciprocating spiral tube with particular reference to the piston cooling application. The flow studied is turbulent upon entering the coils but transits into laminar in the further downstream of the coils. A selection of heat transfer measurements with which the physics of pulsating and buoyancy forces interactively affect the heat transfer along the inner and outer edges of the reciprocating coiled tube is illustrated. The pulsating force with buoyancy interaction causes the considerable heat transfer modifications from the static results. Although enhancing the buoyancy level improves heat transfer, the local Nusselt number in the reciprocating coils is initially impaired from the static value with weak reciprocation; but recovered at the higher level of pulsating force. This study focuses on the development of the experimental procedure that could lead to a physically consistent empirical correlation, which assists to evaluate the local heat transfer in the reciprocating coils by permitting the individual and interactive effects of centrifugal force, torsional force, pulsating force and reciprocating buoyancy on the forced convection to be quantified.
