Takafumi Yamauchi

Detailed Surface Reaction Model for Three-Way Catalyst and NOx Storage Reduction Catalyst

In this research we developed surface kinetic model with detailed reaction mechanisms for simulating reaction dynamics of NO x Storage& Reduction (NSR) Catalyst and three-way catalyst (TWC). Simulation results showed that surface site coverage strongly dominates catalytic reaction characteristics especially in transient state. So we confirmed that the surface kinetic model could play important roles in a useful tool for understanding detail reaction dynamics and searching the optimized operating conditions in the development of automotive catalysts which was always exposed to transient conditions. And the detailed reaction mechanisms in TWC and NSR catalyst were discussed on the basis of the calculated surface site coverage.

Development of a Compact Adsorption Heat Pump System for Automotive Air Conditioning System

Adsorption heat pump (AHP) system is one of the key technologies. We have been developing AHP system utilizing the exhaust heat from the engine coolant system, which can meet the requirements in the automotive application. However, AHP systems have not been used in automotive applications because of its low volumetric power density of the adsorber. In order to improve the volumetric power density of the adsorber, we suggest a compact adsorber which is characterized by honeycombed composite plates of an adsorbent with thermal conductive filler bonded to a plate-type heat exchanger. In the suggested adsorber, the adsorption and desorption rate and the packing density were 1.33 times and 1.36 times larger than a reported coating-type adsorber respectively. The volumetric power density of our adsorber is comparable to that of an mechanical compressor for on board air conditioning system. The developed compact adsorber can contribute to reducing the size and total cost of the AHP system. This technology is to be applicable to the AHP systems not only for automotive application, but also for large-scale air conditioning systems (e.g. factory air conditioning system).