Automobile components are subjected to high dynamic loads and vibrations under operational conditions which needs detailed system analysis for work properly. The torque generated in the engine creates oscillations, and this case occurred at different levels of frequencies. Clutch is one of the important part of automobile powertrain system with torque transmission controlling and vibration damping properties. Metallic helical springs are widely preferred within the clutch discs with their durable mechanic properties against dynamic variables on an automobile. This study develops the novel approach on the time-based investigation of rubber clutch springs, and system optimization for torsional vibration damping using the simulated annealing algorithm method. In this purpose, the torque behavior of the rubber spring instead of the helical spring was investigated by experimentally in time-dependent manner. Rubbers consist of polymer chains which are highly sensitive to dynamic variables such as operation time, frequency and thermal load. The clutch disc which includes rubber damper spring made of NBR (Nitril rubber) is experimentally tested with functional torque measurement at different compression cycle times to observe rubber damper spring viscoelastic time-based behavior. As the next step, 1-D modeling of powertrain system, including rubber clutch damper springs, were subjected to vibration optimization with simulated annealing (SA) algorithm. Thus, the simulated annealing (SA) algorithm was developed, and integrated run is provided with 1-D modeling for optimization in Python script. This methodology accelerates the powertrain system optimization using both rubber and metallic damper types with eliminating many of real vehicle testing and saving cost and time before the production phase. Also, results give an idea on the importance of 1-D simulation before design modeling of rubber clutch damper system based on time-dependent conditions.

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Automobile clutch system components are subjected to high dynamic forces under operational conditions. The clutch disc is in charge of damping the vibrations coming from the engine properly to improve driving comfort and transmitting the torque. Torque transmission role of a clutch disc is achieved with a damper system which consists of metallic springs conventionally.

Clutch is one of the most important components in automobile powertrain systems. The torque generated in an engine is transmitted by friction faces of a clutch disc between pressure plate and flywheel. In addition to transmitting engine torque, the clutch disc has the task of preventing torsional engine vibrations from reaching the powertrain. To achieve this task, the clutch disc is fitted with torsional dampers which have metallic compression springs. Another solution is to use rubber springs instead of metallic ones. Recently rubber materials are widely demanded particularly in the automotive industry with the advantages of high damping capability, lightweight and low cost. In a traffic jam condition, numerous engagement and disengagement create incremental thermal load and temperature increase due to slippage between friction faces. The temperature level in the clutch house is expected to affect material properties of damping components assembled inside the clutch disc. In this paper, the rubber and metallic damper springs were investigated experimentally at the expected temperatures and dynamic loads during driving conditions. Thus, the thermal behavior of rubber springs in the clutch system was observed with the novel approach. Damper torque characteristics, cooling rates and loss of stiffness change with time and frequency have been revealed comparatively. Safety factor coefficient selection for damper torque has the major importance at the system in which the stiffness varies within time due to dynamic loads. In conclusion, the clutch disc used with rubber springs needs correct analysis in terms of design. Results show that how to safety actor should be chosen more attentively for clutch disc used with rubber spring on automobiles and related calculations have to be done before the design phase.

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