Design of a mechanically closed-loop test rig for testing aviation industry's gearboxes

Due to the wide usage of rotary equipment and the necessity of their testing for maintenance and repair, test rigs have become necessary. The mechanical closed-loop test rig developed in Sharif University of Technology branch of ACECR (Academic Centre of Education, Culture and Research) is a test rig with low energy losses that is suitable for testing high power gearboxes such as aerospace or wind turbine gearboxes. It can be loaded up to 489Hp at a maximum speed of 3000 rpm, and the test components can be tested in different testing conditions including a variety of torques and speeds. This paper describes the preliminary, conceptual, and detailed design, steps including frame work design, control system design, hydraulic system and torque generator design asn well as a dynamic and static analysis of the whole system. Also a simplified model of the system is presented and qualified, and some data of test rig's working conditions is presented. These data includes the temperature change of the gearboxes, their vibration in time, and also the variation of torque, hydraulic pressure, and motor speed. Furthermore, the relation between these parameters is investigated to determine the behaviour of the system. The validity of the system's dynamic modelling is also investigated and verified.