Stage IIIB/ Tier 4i and Stage IV/Tier 4 Engine System Integration in Agricultural Tractors

摘要

Future EU and USA exhaust emission legislations Phase 3B / Tier 4i can be met by means of two main engine and exhaust after treatment schemes (EAS): EGR + DPF (EAS for particulate matter) or SCR (EAS for nitrogen oxydes). Final legislations step (Stage 4 / Tier 4) will require EGR in combination with exhaust after treatment for both NO_x and PM emissions. More powerful and flexible vehicle thermal management will be also needed to meet exhaust emission legislation requirements and to fulfil the needs of real life operating conditions. Engine systems, namely exhaust emission control technologies and thermal management, will strongly affect the dimensions, costs, performance and layout of agricultural tractors. Therefore the selection of the main technology scheme and the subsequent variants combination is a key issue in order to offer to the end user tangible benefit in terms of overall vehicle performance with minimized cost impact.