Design, Simulation, and Fabrication of a Copper-Chrome-Based Glass Heater Integrated into a PMMA Microfluidic System

In this paper, the development of a copper-chrome-based glass microheater and its integration into a Polymethylmethacrylate (PMMA) microfluidic system are presented. The process highlights the importance of an appropriate characterization, taking advantage of computer-simulated physical methods in the heat transfer process. The presented system architecture allows the integration for the development of a thermal flow sensor, in which the fluid flows through a 1 mm width × 1 mm length microchannel across a 5 mm width × 13 mm length heating surface. Using an electrothermal analysis, based on a simulation and design process, the surface heating behavior curve was analyzed to choose a heating reference point, primarily used to control the temperature point within the fluidic microsystem. The heater was characterized using the theory of electrical instrumentation, with a 7.22% error for the heating characterization and a 5.42% error for the power consumption, measured at 0.69 W at a temperature of 70 °C. Further tests, at a temperature of 115 °C, were used to observe the effects of the heat transfer through convection on the fluid and the heater surface for different flow rates, which can be used for the development of thermal flowmeters using the configuration presented in this work.