Experimental determination of convective heat transfer coefficient in WEDM

An experimental determination method of the convective heat transfer coefficient in WEDM is introduced. A special device is developed to measure the average temperature increment of the wire after a period of short circuit discharges, and the thermal load imposed on the wire is also tracked and recorded in advance. Then, based on the thermal model of the wire, the convective coefficient can be calculated accurately. With this method, the effect of the coolant flushing pressure on the convective coefficient is estimated. Experiments are also carried out inside and outside a previously cut profile to examine the influence of the kerf on the convective coefficient.