MATHEMATICAL MODEL OF INDIVIDUAL LUBRICATION SYSTEM FOR BEARING ASSEMBLY OF INTERNAL COMBUSTION ENGINE TURBOCHARGER

Internal combustion engines are equipped with turbochargers to increase their power, while the design of the engine itself practically remains unchanged. The turbocharger operates at high rotor speeds (25000...110000 min(-1)), as well as at high temperature conditions (650...700 degrees C). The problem is compound by the fact that the bearing assembly receives a lubricant that was involved in lubrication of the rubbing elements of the entire engine, since the turbocharger bearing lubrication system is combined with the engine lubrication system. This leads to increased wear on the turbocharger bearing and a reduction in its service life. These circumstances require an increase in the lubrication efficiency of the turbocharger-bearing unit. To solve this problem, we have developed a new design of an individual lubrication system for the internal combustion engine turbocharger bearing. The design solution allows to provide the turbocharger bearing assembly with lubricant in the engine start mode and after it stops during the rotation of the rotor by inertia for 90 seconds. The article deals with the design calculation of the individual turbocharger bearing lubrication system. In order to be able to calculate the design of an individual turbocharger bearing lubrication system for any engine, a mathematical model has been developed. The final formulas for calculating the parameters of the turbocharger bearing lubrication system are present, as well as specific calculation results for the most common brand of turbocharger.