This paper presents a theoretical analysis of the response of a thermocouple placed in a reciprocating engine. The manner in which the temperatures recorded by the thermocouple lag behind and are attenuated from the fluctuating fluid temperatures because of thermal inertia of the thermocouple is analysed. A method is suggested for computing the true fluid temperatures from the measured temperatures in an engine under both motoring and operating conditions. This compensation technique allows the use of larger, more robust thermocouples without losing the rapid time response of very small thermocouple wires.
KawaharaN.TomitaE.‘In-situ unburned gas temperature measurement in a spark ignition engine using laser interferometry.’ SAE paper 2005-01-0646, 2005.
2.
RothamerD.SnyderJ.HansonR.SteeperR.‘Two-wavelength PLIF diagnostic for temperature and composition.’ SAE paper 2008-01-1067, 2008.
3.
AlessandroG. C.ViolinoP.‘Thermometry by CARS in an automobile engine.’J. Phys. D: Appl. Phys.16 (1983): 1583–1594.
4.
RaoV. K.GardinerD. P.BardonM. F.‘Effects of gas leakage and crevices on cold starting of engines.’ SAE paper 940078, 1994.
5.
RaoV. K.BardonM. F.‘Convective heat transfer in reciprocating engines.’Proc. IMechE, Part D: Transport Engineering199 (D3) (1985): 221–226.
6.
GulderO. L.‘Combustion gas properties: part III – prediction of the thermodynamic properties of combustion gases of aviation and diesel fuels.’Trans. ASME, J. Engng Gas Turbines Power110 (1988): 94–99.
7.
McBrideB. J.GordonS.‘Computer program for calculation of complex chemical equilibrium compositions and applications II. Users manual and program description.’ NASA Reference Publication 1311, Lewis Research Center, National Aeronautics and Space Administration, Cleveland, Ohio, USA, June 1996.
