Thermodynamic analysis of a novel thermoelectric microdroplet sensor

Instead of directly gauging microdrop size with expensive facilities, one can resort to a new type of droplet sensor, the design, measurement principle, and testing of which are introduced in this paper. This sensor transfers the thermopile signal induced by temperature sway in the course of droplet impinging on a regionally warmed membrane. Based on general heat conduction equation and spherically symmetric droplet-vaporization model, the enthalpy change and phase transition of concerned microdrops are explored. Derivation of essential equations is demonstrated in detail, and the mathematical tractability of such quiescent case is confirmed by experiments. The measuring method is finally suggested in the conclusion.