an apparatus and method for measuring coolant quenching rates includes a metallic disk supported on a ceramic tube , the metallic disk including a plurality of thermocouples therein . the metallic disk is heated from above by a torch and coolant is sprayed on the underside of the disk . changes in temperature throughout the metallic disk are detected by the thermocouples to measure various quenching parameters . the metallic disk may be surrounded by insulating material to maintain heat flow through the disk in a predetermined manner . by heating , insulating and cooling the metallic disk , temperature measurements can be quantified into heat transfer rates to investigate various heat transfer mechanisms and different types of coolants .