A novel sensor technique is proposed to visualize the readily spatiotemporal behavior of a fluctuating temperature field of airflow. Two temperature probes were fabricated: one is a rod-type probe consisting of 24 two-thermocouple sensors set in line and the other is a plane-type one consisting of 64 two-thermocouple sensors arrayed on a two-dimensional grid (8×8 points). Each two-thermocouple sensor used in these probes was composed of two fine-wire thermocouples (type K) of unequal diameters, e.g., 25μm and 51μm. An adaptive response-compensation scheme was applied to accurately reconstruct rapidly-changing airflow temperatures. The plane-type probe enables visualization of fluctuating temperature fields of an artificially disturbed hot-air jet and adequate capture of the spatiotemporal behavior of a rapid circular motion of hot-air jet blown out from a hair dryer. A time-constant estimation scheme was proposed to estimate instantaneous time-constants which serve as a basis for a real-time response compensation technique for multidimensional temperature measurement. In addition, by scanning a temperature field with the rod-type probe, the temperature distribution can be reconstructed in one-dimensional space and time. This quasi two-dimensional visualization can become a prototype of a "scanner" for fluid temperature fields.
