Temperature and heat flux errors in thin film thermometry

Figures & data

Figure 1. (a) Photograph of sensor and (b) grid model of sensor.

Figure 2. (a) Final grid and (b) split view of model showing wires and epoxy.

Figure 3. Grid sensitivity: solution time histories for four time steps (the last two are indistinguishable).

Figure 4. (a) Typical temperature contours and (b) temperature histories.

Figure 5. (a) Imposed heat flux; (b) recovered simulated data for undisturbed (upper) and sensor (lower) temperatures; and (c) recovered heat fluxes (errorless data).

Figure 6. Results with (a) noisy ‘undisturbed’ data and (b) noisy ‘sensed’ data.

Table 1. Contact resistances.

Description	Thickness (m)	Contact resistance (m^2 K W^−1)
Aluminium 10 µm roughness, air, 100 kNm^−2 pressure 12	–	2.75E−4
Stainless steel, vacuum, 100 kNm^−2 pressure 12	–	6E−4 to 25E−4
Conduction air gap	9.0E−6	3.5E−4
Conduction air gap	9.0E−5	35E−4

Figure 7. (a) Resulting temperatures with thermal contact resistance and (b) heat fluxes computed with temperature histories using ‘undisturbed’ sensitivity.

Figure 8. (a) Sensitivity coefficient functions and (b) results with noised sensor data using sensor sensitivity.

Figure 9. Heat flux results for small resistance case using sensor dynamics to determine sensitivity coefficients. Estimated flux and exact value are indistinguishable.