Device and methods for the measurement of energy transfer in experiments involving thermal and electrical injuries of skin.
This work is part of a larger investigation aiming at tracing differences between injuries caused by heat and electricity. Electrodes and heaters similar to the electrodes of an electric cattle baton are used to dissipate approximately 40 joules in 40 seconds in pig skin. Voltages in the range 40-60 volts (AC or DC) are applied via stainless steel electrodes and temperatures in the range 50-100 degrees C are applied via heaters made of copper wire. Heat transfer is controlled by electronically regulated heaters utilizing the temperature dependence of the heater wire itself as a thermometer. Transfer of electricity takes place from either commercial DC supply, from transformed voltage from the mains or from a sine voltage generator connected to a power amplifier. The energy transfer is in all cases measured by electronic integration of the dissipated power in time. The power supplied to th electrodes or the heaters is found by electronic multiplication of the applied voltage and current. Typical power vs. time curves are presented.