Concept Phase Powertrain Development for NVH Using the Optimization Technique

One of the primary excitation sources in a passenger car comes from the powertrain [1]. Refinement of powertrain induced noise is the most critical tasks during a vehicle refinement. Due to ever increasing demand for reduced design and development cycle, most critical decisions have to be made at the concept stage. Powertrain radiated noise is one of the most important performance factor that must be evaluated during the concept stage. Solution time for calculating the radiated noise using the existing acoustic solvers is very high and requires very expensive resources like software and hardware. Arriving the optimal design with conventional method is very tedious job. A new method has been adopted for identifying the critical areas and coming up with the optimal design modifications within a short span of time. Powertrain radiated noise has been calculated with the help of acoustic solver. Topology optimization [2] is used at an early stage of the vehicle development process to arrive at a conceptual design proposal that is then fine-tuned for performance and manufacturability. This replaces time consuming, costly design iterations (manual) and reduces design development time. In order to have effective topology optimization, we must reduce the time spent on calculating the accurate simulation results [3] for each iteration. Proposed methodology of combining super elements with the topology optimization provides a tenfold benefit in the computational time. A DMIG Model is prepared in the Altair optistruct which gives us the component specific residual runs for ERP with reduced runtime. A topology optimization problem has been set up for minimizing weight with reducing the ERP. In this problem manufacturing constraints are also considered in the early stages of the design cycle. With this procedure, noise radiation for the full powertrain is reduced to a considerable level in a short span of time.