Bottom dead centre

To say that another way, at 3000 rpm, the piston in the cylinder moves from Top Dead Centre to Bottom Dead Centre in lOmS. 

Whatever the specification system, successful engine lubricants must satisfy a wide range of functions. They must ensure the operating reliability of the many friction points in engines. Table 17.1, but additionally must seal and cool the piston/cylinder interface and also transport metallic debris, soot and degradation products to the filter. Hydrodynamic and elastohydrodynamic conditions exist in bearings, whilst boundary conditions exist at the top and bottom dead centres (TDC and BDC) of sliding piston simple harmonic motion. Temperatures can vary from -50°C at start-up to 100°C-i- sump temperatures and >300°C peak values under the piston crown. The issues to be addressed for each lubricant formulation are included in Table 17.1. 

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