Beerens, C., Mueller, A., and Karrip, K., "Transient Valve Temperature Measurement (TVTM)," SAE Technical Paper 2017-01-1066, 2017, doi:10.4271/2017-01-1066.
As emissions regulations and carbon footprint are more and more demandingly controlled, thermal efficiency of engine components must be optimized. Valve group components have to allow for ever increasing temperatures, endure aggressive condensates or even contribute directly to rising efficiency and emissions demands. Even with integrated and cooled exhaust manifolds, the exhaust valves are meeting full combustion temperatures, especially for stoichiometric combustion.MAHLE has developed a new technology in order to measure valve temperatures in real time, i.e. Transient Valve Temperature Measurement (TVTM).This is a complex methodology using thermocouples installed inside of the valves, offering the possibility to run the engine at different conditions, without any functional changes in the valve train system at all. Specifically valve rotation is not affected and thus temperatures all around the valve seat can be captured during rotation. The test is cost effective, using series’ components.With the application of this TVTM testing method, results are supporting the confirmation of design limits, material fatigue, mapping of valve rotation etc. All this is possible across the entire engine operating range, avoiding blind spots in valve temperature measurements. In this paper, a description of the TVTM technique, some typical results and also the benefits in comparison with standard thermometric valve temperature measurements are presented.