By looking current scenario, engine development lead time was reducing day by day to enter early in the competitive market and to compete as early as possible. During initial engine development phase, it was very important to know how engine operating temperatures were affecting to piston pack and related system. Conventionally temp plug method was used to capture the piston temperature, but it was time consuming, much costly, for every test condition, new temp plug pistons required, if unfortunately, any hot shutdown happened during the test, again full test needs to be restarted with new set of temp plug pistons and many more limitations. So, for Cummins engine we used Telemetry technique to measure the piston temperature ONLINE and in real time.
Piston telemetry enables the telemetric transfer of piston data from internal reciprocating and rotating components. The pistons had wireless telemetry to send real time steady state and transient data from within engines. The piston telemetry data transfer devices used to meet the stringent demands of harsh operating environments. Piston telemetry transmitters can be run using battery power or inductive power supply.
Type thermocouples and a microwave wireless telemetry system were used to gather real time temperature data on the piston near each metallurgical sensor. Number of pairs of metallurgical temperature sensors were installed in the piston with a thermocouple junction in-between. The engine was operated in various speeds, loads and operating boundary conditions. During the test, continuous temperature data at each of the sensor locations was monitored and recorded using the telemetry system.
Results are compared with calibrated FEA model within 5% variation and its analogous.
Engine program will have enough time for doing the changes in piston during early stage of program.