A device to measure high-speed wear characteristics of material combinations was to be designed and built. One part of the test protocol included characterization of the thermal history (temperature and heat flux) throughout the test pieces including estimates as close to the wear interface as possible.
In the design phase of the test apparatus, isoflux and thermal explosion boundary conditions were used to analytically model the temperature response in candidate materials in order to provide working estimates for the selection and configuration of the temperature measurement systems. Figure 1 shows transient temperature profiles at several depths in a candidate material as calculated for a typical short duration test event.
Figure 1. Transient Temperature Profiles
Thermocouple selection and placement based on the analytical estimates were made for the test pieces. Then, an extensive sensitivity analysis was carried out in order to estimate bounds on the range of possible results expected to be seen under test conditions. The sensitivity analysis indicated that the uncertainty in measured temperatures would not overwhelm the data reduction and that reliable estimates of interfacial heat flux could be made from the measured data. An analytical/numerical inverse problem solution was developed in order to provide complete temperature and heat flux estimates from limited temperature measurements. Figure 2 shows an inverse solution (in green) based on noisy simulated temperature inputs.
Figure 2. Inverse Problem Solution Result
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