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3 interesting numbers from VTMS 12

By May 28, 2015April 22nd, 2016No Comments

I just returned from VTMS 12 in Nottingham. In addition to the paper that CSEG delivered, there were many interesting papers focusing on Waste Heat Recovery, thermal management concepts enabling faster warm-up for higher fuel economy and development of computational methodologies to enable optimization of an increasing complex system – many of them similar to those being pursued by the North American OEMs.

In my opinion, there were 3 papers, and 3 numbers, which quantified the problems and the benefits. Here they are:

1.Waste Heat Recovery – TEG (or Thermo-electric generator) that harnesses heat in exhaust to generate electric energy has a cost-benefit ratio problem. It costs too much to recover a given amount of power compared to other technologies. 91% of TEG’s costs come from the thermo-electric material such Tellurium. The world’s resources at the current moment are about 20K tons of Tellerium which can equip about 10 million cars (corresponding to 3 months of production). However, efforts are being put in by few European OEMs and Tier 1 suppliers in reducing TEG material and a more innovative applications of the concept. Jaguar-Land Rover is in a second stage of a >3M Euros project exploring TEGs among other waste heat recovery technologies. I wonder what a synthetic replacement for Tellerium would look like. If you hear of a company developing it – please send the stock tip my way.

2.Another fascinating paper looked at impact of TEG location (from manifold to tail pipe) and different drive cycles (NEDC, WLTC and CADC) and concluded the benefits are highest (~1.75% reduction in fuel consumption when TEG are closest to manifold and for the CADC driving cycle (most aggressive drive cycle of the three) and a net negative benefit if the location was at the tailpipe for the NEDC drive cycle.

3.Engine Encapsulation – Besides the usual thermal management challenges that were discussed, it was interesting to note that a number of the European OEMs are actively pursuing some form of engine encapsulation as a thermal management strategy. The strategy, which was approved for the Mercedes-Benz S 300 BlueTEC HYBRID by the EU, shows an average fuel saving of up to 1.5 litres per full tank over the course of a year in testing. The concept involved keeping the heat inside the engine compartment – even if the vehicle is stopped for some time leading to higher engine temperatures and reduced friction, minimizing cold-starting losses and cut CO2 emissions.

There was also significant discussion on the numerical tools and methods used to evaluate the interaction of various technologies and optimize their performance to harness the most benefits. This is the future of thermal system modeling including modeling iteratively along with testing, to develop a deeper understanding of the system.




Sudhi Uppuluri is the Technical Director and Co-Founder at Computational Sciences Experts group. He has over 15 years of experience in system simulation of automotive and aerospace systems. He worked as a consulting engineer and sales manager at Flowmaster USA for 8 years. He has various technical publications on related subjects in SAE and AIAA journals. He holds a Masters in Aerospace Engineering from the University of Illinois at Urbana-Champaign and a Certificate in Strategy and Innovation from the MIT Sloan School of business.

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