A two-thermocouple sensor characterization method for use in variable flow applications is proposed. Previous offline methods for constant velocity flow are extended using sliding data windows and polynomials to accommodate variable velocity. Analysis of Monte-Carlo simulation studies confirms that the unbiased and consistent parameter estimator outperforms alternatives in the literature and has the added advantage of not requiring a priori knowledge of the time constant ratio of thermocouples. Experimental results from a test rig are also presented.
Bradley, D. and Matthews, K.J.1968: Measurement of high gas temperatures with fine wire thermocouples . Journal of Mechanical Engineering Science10, 299-305.
2.
Forney, L.J. and Fralick, G.C.1994: Two wire thermocouple: frequency response in constant flow. Review of Scientific Instruments65, 3252-57.
3.
Hung, P., McLoone, S., Irwin, G. and Kee, R.2003: A total least-squares approach to sensor characterisation. Proceedings of the 13th IFAC Symposium on System Identification, Rotterdam, 27-29 August, 337-42.
4.
Hung, P., McLoone, S., Irwin, G. and Kee, R.2005a: A difference equation approach to two-thermocouple sensor characterization in constant velocity flow environments. Review of Scientific Instruments76, Paper No. 024902.
5.
Hung, P., McLoone, S., Irwin, G. and Kee, R.2005b: Unbiased thermocouple sensor characterisation in variable flow environments. Proceedings of IFAC World Congress , Prague, 4-8 July.
6.
Kee, R.J., O'Reilly, P.G., Fleck, R. and McEntee, P.T.1999: Measurement of exhaust gas temperature in a high performance two-stroke engine. Transactions of SAE Journal of Engines107, 2413-23.
7.
Kee, R.J., Hung, P., Fleck, B., Irwin, G., Kenny, R., Gaynor, J. and McLoone, S.2006: Fast response exhaust gas temperature measurement in IC engines. Proceedings of SAE 2006 World Congress , Detroit, MI, 3-6 April, SAE Paper No. 2006-01-1319.
8.
Ljung, L.1999: System identification: theory for the user. second edition. Prentice-Hall.
9.
McLoone, S., Hung, P., Irwin, G. and Kee, R.2006: Exploiting a priori time constant ratio information in difference equation two-thermocouple sensor characterization. IEEE Journal of Sensors6, 1627-37.
10.
McLoone, S., Hung, P., Irwin, G. and Kee, R.2008: Difference equation sensor characterization algorithms for two-thermocouple probes. Transactions of Institute of Measurement and Control30, 173-99.
11.
O'Reilly, P.G., Kee, R.J., Fleck, R. and McEntee, P.T.2001: Two-wire thermocouples: a nonlinear state estimation approach to temperature reconstruction. Review of Scientific Instruments72, 3449-57.
12.
Petit, C., Gajan, P., Lecordier, J.C. and Paranthoen, P.1982: Frequency response of fine wire thermocouple. Journal of Physics Part E15, 760-64.
13.
Tagawa, M. and Ohta, Y.1997: Two-thermocouple probe for fluctuating temperature measurement in combustion - rational estimation of mean and fluctuating time constants . Combustion and Flame109, 549-60.
14.
Tsuji, T., Nagano, Y. and Tagawa, M.1992: Frequency response and instantaneous temperature profile of cold-wire sensors for fluid temperature fluctuation measurements. Experiment in Fluids13, 171-78.
