Study of Effect of Ethanol Blending on Performance & Fuel Economy of Naturally Aspirated Gasoline Engine and Engine Hardware Optimization Potential 2022-28-0024

Blending locally produced ethanol with petrol will help India strengthen its energy security. India is making steady progress in raising the share of ethanol having increased to 8.1% in ethanol supply year 2020-21 (Dec-Nov) with target to achieve 10% ethanol blending in the ethanol supply year 2021-22. In future, Government of India is planning to start supply of 20% ethanol blended petrol from Apr’23 and to cover PAN India by Apr’25. Pure ethanol has lower calorific value than Petrol thus ethanol blended petrol will always have calorific value lower than that of petrol thereby deteriorating Fuel economy. On the other hand, ethanol blended petrol will have higher RON compared to petrol. Higher RON reduces knocking tendency thereby providing calibration optimization potential to optimize Spark timing. Optimized spark timing can help in improving Full Load Torque by reducing Phasing losses and operating closer to MBT. This paper shows impact of ethanol blended gasoline (E20) on Engine Performance & Fuel economy with E20 Optimized Calibration highlighting the effect of both Calorific value and RON. This paper also highlights the potential to recover some part of Fuel Economy loss due to lower calorific value of ethanol blended fuel by optimizing Compression Ratio and Gear Ratio.