Due to new federal regulations and higher environmental awareness, the market demands for high fuel economy and low exhaust emission engines are increasing. At the same time customer demands for engine performance, NVH and reliability are also increasing. It is a challenge for engineers to design an engine to meet all requirements with less development time. Currently, the new engine development time has been trimmed in order to introduce more products to the market. Utilizing CAE technology and processes in an engine development cycle can enable engineers to satisfy all requirements in a timely and cost-effectively way.
This paper describes a new Powertrain Virtual Analysis Process which has been successfully implemented into Chrysler PTCP (Powertrain Creation Process) and effectively utilized to shorten and improve the product development process. This new virtual analysis process guides the product development from concept through the production validation phases. Based on the new process, CAE engineers collaborate with product development, quality, dyno/vehicle test and design CoE (Center of Excellence) teams to establish the concept study plans and quality documents (boundary diagram, functional model, DFMEA and DVP&R) of components and systems; complete and execute the CAE plans according to DVP&Rs; optimize the mechanical and reliability test plans depending on CAE contribution; assess the product design risk based on CAE results and existing test data at each design phase before physical tests start; utilize CAE tools to provide solutions when failures are found during tests; and close loop of virtual analysis process by summarizing lessons learned from product development.
This paper summarizes CAE technologies used in this new virtual analysis process during a new Chrysler I4 engine design and development. These technologies include NVH, 1D engine performance, CFD gas/coolant flow, conjugate heat transfer, crankcase breathing, lubrication, and structure durability. The new virtual analysis process helped meet challenging engine program targets that required 88% new engine parts (excluding carry over fasteners/sealants) in only 22 months from program approval to start of production.