Microfluidic heated gas jet shape analysis by temperature scanning

A method for thermal jet shape measurement of microfluidic heated gas jets by scanning with a miniature thermocouple is presented. The spatial resolution is determined by the size and shape of the thermocouple, and better than 100 mu m resolution is easily available. The method is demonstrated by measuring the temperature distributions of heated gas jets of microfluidic heated nebulizer chips. Micronozzles fabricated with different technologies are shown to produce clearly distinguishable gas jets. A computer simulation is used to study the dependence of temperature and velocity distributions.