Online Monitoring Solutions of Efficiency for Automotive EGR Heat Exchangers Bianca Maria Vaglieco, Simona Silvia Merola, Adrian Irimescu, Vasco Zollo and Raffaele De Marinis E3S Web Conf., 162 (2020) 01003 Published online: 07 April 2020 DOI: 10.1051/e3sconf/202016201003