Ryou Y.S.,Seoul National University |
Lee J.,Seoul National University |
Lee H.,Hyundai Kia Motors R and nter |
Kim C.H.,Hyundai Kia Motors R and nter |
Kim D.H.,Seoul National University
Catalysis Today | Year: 2017
Pd/CeO2 catalyst hydrothermally aged at 750°C for 25h was employed for NO adsorption at low temperature (80-160°C). For comparison, Pt or Pt-Pd supported on CeO2 or Al2O3 catalysts were also applied. Analysis of the hydrothermally aged catalysts clearly indicates that PGM (Pt and/or Pd) on CeO2 is more resistant to sintering than that on Al2O3 support. Reducibility test of Pd/CeO2 by H2-TPR exhibits H2 spillover from Pd to CeO2 support, attributed to the strong interaction between Pd and CeO2. NO adsorption/desorption results demonstrate that CeO2-based catalysts exhibit superior NO adsorption ability than Al2O3-based catalysts. In addition, PGM/CeO2 catalysts shows the desirable desorption temperature for cold start application. The influence of reactant in stream, NO adsorption time, and temperature on low temperature NO adsorption over Pd/CeO2 is also examined to advance the understanding of NO adsorption/desorption behavior. DRIFT results of adsorbed NOx species on Pd/CeO2 during NO adsorption/desorption prove that NOx desorption peaks at 250, 300, and 450°C originate from weakly bound nitrite, nitro-nitrito species, and nitrate species, respectively. In Pd/CeO2 catalyst, Pd plays a role in providing additional NO adsorption site arising from the intimate interaction between Pd and CeO2 and promoting the oxidation from adsorbed nitrite to nitrate. It can be summarized that Pd/CeO2 can be a good candidate as low temperature NO adsorption catalyst for cold start application. © 2017 Elsevier B.V.
Ahn K.H.,Hyundai Kia Motors R and nter |
Stefanopoulou A.G.,University of Michigan |
Jankovic M.,Ford Motor Company
IEEE Transactions on Control Systems Technology | Year: 2013
Flexible fuel vehicles (FFVs) can operate on a blend of ethanol and gasoline in any volumetric concentration of up to 85% ethanol (93% in Brazil). Existing FFVs rely on ethanol sensor installed in the vehicle fueling system, or on an ethanol estimation based on air-to-fuel ratio (AFR) regulation via an exhaust gas oxygen (EGO) or λ sensor. The EGO-based ethanol detection is desirable from cost and maintenance perspectives but it is known to be prone to large errors during mass air flow sensor drifts. Ethanol content estimation can be realized by a feedback-based fuel correction of the feedforward-based fuel calculation using an exhaust gas oxygen sensor. When the fuel correction is attributed to the difference in stoichiometric air-to-fuel ratio (SAFR) between ethanol and gasoline, it can be used for ethanol estimation. When the fuel correction is attributed to a mass air flow (MAF) sensor error, it can be used for sensor drift estimation and correction. Deciding under which condition to blame (and detect) ethanol and when to switch to sensor correction burdens the calibration of FFV engine controllers. Moreover, erroneous decisions can lead to biases in ethanol estimation and in MAF sensor correction. In this paper, we present AFR-based ethanol content estimation, associated sensitivity and dynamical analysis, and a cylinder air flow estimation scheme that accounts for MAF sensor drift or bias using an intake manifold absolute pressure (MAP) sensor. The proposed fusion of the MAF, MAP, and λ sensor measurements prevents severe misestimation of ethanol content in flex fuel vehicles. © 1993-2012 IEEE.
Hee L.T.,Hyundai Kia Motors R and nter |
Yun M.J.,Hyundai Kia Motors R and nter |
Jung W.W.,Hyundai Kia Motors R and nter |
Min B.H.,Hyundai Kia Motors R and nter
SAE Technical Papers | Year: 2010
The various seat problems are happening in the field. Customers are getting more sensitive to the quality of a vehicle than ever these days. The long-term accumulated staining of iInterior trim contamination, as a result, is one of the most important factors in regarding that of the vehicle and newly reflected in IQS in 2007 and VDS in 2008 respectively. In particular, seat staining contamination has been mainly responsible for the decrease of vehicular marketability and used-car price. Therefore seat must be improved not to be stained contaminated easily. The stain accumulation contamination mechanism of both natural genuine and artificial leather seats is different from that of fabric cloth seat and we hereby verified them systematically. We developed the test method regarding the actual-conditioned wears (abrasions), soil contamination resources and environment circumstances and that it'll be of service to the vehicle development test. Moreover, 153 fabric samples genuine cloths, which are used for HKMC fabric cloth seat, are classified under six clusters, and 29 representative samples are chosen. With these results analyzed, design guide was finally completed and that it leads us to the conclusion that which fabric cloth is the strongest to the staining contamination from the design concept stage. Copyright © 2010 SAE International.