Condition monitoring of the accessory belt in automotive engine at its critical speeds

This paper presents experimental results of condition monitoring of the accessory belt in automotive engine at its critical speeds. At first, accessory belt critical speeds were detected by measuring its lateral vibration with laser displacement device during four run-up tests. These tests were done from 1000 rpm to 6000 rpm by four combinations of engine load and accessories (engine: full/no load, accessories: on/off). During the tests, belt temperature was regulated near 80°C by a heating module. Based on these critical speeds, a durability test was performed and some parameters were measured. During durability test, scheduled measurements were included accessory belt parameters (such as: belt lateral vibration, belt static tension, belt length, belt mass, belt hardness) and accessory drive parameters (such as: alternator ampere, cooler compressor pressure, acyclic of accessories pulleys and tensioner position).

Keywords:

Accessory belt , Critical speeds , Lateral vibration , durability test