Combustion Chamber Gas Temperatures by a Benzene Light-Absorption Technique
730082
02/01/1973
- Event
- Content
- Several techniques have been presented in the literature for measuring mixture temperatures in internal combustion engines during the compression process up to the time of knock. This paper describes a new method based on the light-absorbing properties of benzene vapor and presents engine data based on this technique.The ultraviolet light absorption coefficient of benzene vapor has been measured over a temperature range of 300-1400 K (80-2060 F). This absorption coefficient, which is very sensitive to temperature, is a function of temperature to the eighth power at room temperatures and decreases smoothly to a fourth power function at approximately 1000 K (1340 F).The extreme sensitivity of the absorption coefficient to temperature allows precise determination of gas temperatures during the early part of the compression process in a Cooperative Fuel Research (CFR) engine and throughout compression of the fuel/air mixture. The data quantitatively support an analytical prediction that heat transfer from the chamber wall to the inlet mixture, during the intake stroke, causes increased compression temperature histories.
- Pages
- 13
- Citation
- Haskell, W., Trumpy, D., and Hendrickson, C., "Combustion Chamber Gas Temperatures by a Benzene Light-Absorption Technique," SAE Technical Paper 730082, 1973, https://doi.org/10.4271/730082.