Contribution of Nuclear Physics to Engine Design:Application of Surface Layer Activation to Tappett Rotation Measurements

960711

02/01/1996

Event
International Congress & Exposition
Authors Abstract
Content
To simultaneously reduce wear and friction in automotive valve train systems, a technique for measuring the rotational speed of tappets by placing radionuclide markers in their surfaces has been developed. Using an electrically driven test rig, counting rate variation during camshaft rotation is traced, allowing a mean value of the tappet's rotational speed to be determined. Measurements were performed on a V6 Peugeot engine cylinder head for various geometrical combinations of the cam-to-tappet contact (crown radius of the tappet, cam taper angle), and the dependence of the tappet's rotational speed upon functional parameters (lubricant pressure and temperature, angular speed of the camshaft) was determined. Tappet rotation was found to be strongly affected by camshaft operating speed and the design of the cam-to-tappet contact, and less by lubrication conditions (off pressure and temperature). Results of these studies are discussed in terms of their significance for developing a model to predict tappet rotation speeds in direct-acting overhead valve train systems. It is shown that, as a minimum, the use of radionuclide markers can save much time during engine development.
Meta TagsDetails
DOI
https://doi.org/10.4271/960711
Pages
17
Citation
Monteil, G., Gallmann, A., Sioshansi, P., and Loges, P., "Contribution of Nuclear Physics to Engine Design:Application of Surface Layer Activation to Tappett Rotation Measurements," SAE Technical Paper 960711, 1996, https://doi.org/10.4271/960711.
Additional Details
Publisher
Published
Feb 1, 1996
Product Code
960711
Content Type
Technical Paper
Language
English