Abstract: Heat flow sensor having at least two plates with the heat (thermo) sensitive elements and with holes (openings) for the passage of air flow, so that the tops of both plates with the thermo sensitive elements are placed facing the outer surface of the sensor, so that their openings coincide and the construction provides passage of air through the openings whereby the thermo sensitive elements are located between all the holes of the plates and serially connected on every plate, and then the said sensor (plates) has one common point of connection in the middle of each side so that each sensor has at least three output wires—the total, the output of each plate, and therefore the magnitude and direction of the heat flow, are determined by the difference between the outputs of the two earlier described plates.

Abstract: The invention provides a new system for measuring the heat flow rate between a first and a second medium, the system includes at least two sensor units with signal outputs disposed in a spaced-apart relationship, each of said units including a transducer with apertures allowing fluid to pass through; the transducers are affixed to a first surface on the first medium directly or at least indirectly, and a second surface is exposed to the second medium; thus the said system includes at least two different calibration plates with known coefficient of thermal conductivity and said calibration plates inserted into a measuring line (scheme) of both the sensor units and are affixed behind or in front of the sensor units; the signal outputs of the said transducers arrive to a processing unit for determination and measurement of changes in the heat flow between the said first and the said second sensor units.

Abstract: Heat flow sensor having at least two plates with the heat (thermo) sensitive elements and with holes (openings) for the passage of air flow, so that the tops of both plates with the thermo sensitive elements are placed facing the outer surface of the sensor, so that their openings coincide and the construction provides passage of air through the openings whereby the thermo sensitive elements are located between all the holes of the plates and serially connected on every plate, and then the said sensor (plates) has one common point of connection in the middle of each side so that each sensor has at least three output wires—the total, the output of each plate, and therefore the magnitude and direction of the heat flow, are determined by the difference between the outputs of the two earlier described plates.