An electrocaloric flowmetering system for ultra-low-volume sprayers

The purpose of this investigation was to develop a flowmetering system for use on ultra low volume (ULV) agricultural sprayers. The experimental data were to provide sufficient information to determine the feasibility of an electrocaloric flowmeter for this use. A theoretical expression was derived from which flow rate through the electrocaloric metering system could be determined. The data were obtained from a laboratory setup of the flow metering system. Tests were conducted with distilled water, Malathion, and Panasol. The independent variables tested were flow rate and liquid temperature. The effect of four levels of each independent variable was measured from the effect it produced on the error percentage between the theoretical and measured flow rate. Values of absolute viscosity and specific heat were determined for Panasol and Malathion. It was found that accuracy of the system was affected by the flow rate, temperature, viscosity, and Reynolds Number of the metered liquid. The system performed satisfactorily with water, but produced considerable error with Malathion and Panasol at the lower flow rates tested.