Eaton (Netherlands)

<div class="section abstract"><div class="htmlview paragraph">Engine and aftertreatment solutions have been identified to meet the upcoming ultra-low NO<sub>x</sub> regulations on heavy duty vehicles in the United States. These standards will require changes to current conventional aftertreatment systems for dealing with low exhaust temperature scenarios while increasing the useful life of the engine and aftertreatment system. Previous studies have shown feasibility of meeting the US EPA and California Air Resource Board (CARB) requirements. This work includes a 15L diesel engine equipped with cylinder deactivation (CDA) and an aftertreatment system that was fully DAAAC aged to 800,000 miles. The aftertreatment system includes an e-heater (electric heater), light-off Selective Catalytic Reduction (LO-SCR) followed by a primary aftertreatment system containing a DPF and SCR. The e-heater was capable of providing up to 10 kW, however for the purpose of this project, lower power settings of 2.5 kW and 5 kW were studied in combination with CDA for lowest possible CO2 emissions. Test cycles included the heavy duty FPT (hot and cold), a low load cycle, a beverage cycle, and a stay hot operation. The data found in this study show how the application of a low power e-heater enables an engine with CDA and an aftertreatment system after 800,000 miles aging to meet ultra-low NO<sub>x</sub> emissions with minimum CO<sub>2</sub> penalty.</div></div>

The growth in the renewable energy sector changes the power flow, grid codes and modes of operation towards a “Everything as a Grid” concept. To ensure system reliably in this environment, live data on power flow direction, distortion and other parameters is essential. This paper will highlight the advantages of using sensors using a case of introducing/upgrading a renewable energy grid. This will also include specific applications such as cable pooling of multiple sources on a single grid connection and power factor improvement providing the possibility to actively request reactive power from renewables.

PurposeThe introduction of a linear safety factor to address peak local specific absorption rate (pSAR10g) uncertainties (eg, intersubject variation, modeling inaccuracies) bears one considerable drawback: It often results in over‐conservative scanning constraints. We present a more efficient approach to define a variable safety margin based on the conditional probability density function of the effectively obtained pSAR10g value, given the estimated pSAR10g value.MethodsThe conditional probability density function can be estimated from previously simulated data. A representative set of true and estimated pSAR10g samples was generated by means of our database of 23 subject‐specific models with an 8‐fractionated dipole array for prostate imaging at 7 T. The conditional probability density function was calculated for each possible estimated pSAR10g value and used to determine the corresponding safety margin with an arbitrary low probability of underestimation. This approach was applied to five state‐of‐the‐art local SAR estimation methods, namely: (1) using just the generic body model “Duke”; (2) using our model library to assess the maximum pSAR10g value over all models; (3) using the most representative “local SAR model”; (4) using the five most representative local SAR models; and (5) using a recently developed deep learning–based method.ResultsCompared with the more conventional safety factor, the conditional safety‐margin approach results in lower (up to 30%) mean overestimation for all investigated local SAR estimation methods.ConclusionThe proposed probabilistic approach for pSAR10g correction allows more accurate local SAR assessment with much lower overestimation, while a predefined level of underestimation is accepted (eg, 0.1%).

A determining indication for contact wear of a vacuum interrupter (VI) is the cumulative transferred charge (Q cum), during the time between separation of the contacts, and the moment that the current is interrupted. The corresponding contact wear can be expressed in net loss of contact material (in µg/A·s or µm/A·s). Standard vacuum circuit-breakers (VCB's) have a random opening on the current wave, so the contact wear is virtually equally distributed over both contacts at a large number of operations. For Eaton VCB's the total number of interruptions of short-circuit current (I sc) is determined, based on actual switching tests. The number of fault interruptions is dependent on, e.g. allowed contact wear ε (standard VI: ε = 3 mm); choice of contact material; contact configuration (transverse magnetic field or axial magnetic field); opening time of the VCB; frequency (f) and time-constant (τ) of the network (International Electrotechnical Commission (IEC) standard is τ = 45 ms); RMS value of the fault current to interrupt; switching angle (γ) of initiation of the fault current; and switching polarity of current (random or always unipolar). Besides determining the allowed total number of random interruptions as function of the symmetrical fault current, the critical transferred charge and peak current is determined where a VI is still able to interrupt. The maximum values are based on certification testing. They generally occur during the T100a O-operations according to IEC 62271-100. Based on these maximum values, a VCB can be reclassified for interrupting I sc for practical situations, e.g. in networks with other time constants. Reference is made to IEC 62271-100 regarding the test T100a in the current edition 2 (2008) and also the treatment in the upcoming Amd.2 (17A/1118/CDV) is discussed. Some examples are evaluated.

<div class="section abstract"><div class="htmlview paragraph">Several diesel passenger car boosting systems were studied to assess their impact on vehicle performance and fuel economy. A baseline 1.5L diesel engine model with a single VGT turbocharger was obtained through Gamma Technologies' fast running model library. This model was modified to explore multiple two stage boosting systems to represent the anticipated architecture of future engines. A series sequential turbocharged configuration and a series turbocharger-supercharger configuration were evaluated. The torque curves were increased from that of the original engine model to take advantage of the increased performance offered by two stage boosting. The peak cylinder pressure for all models was limited to 180 bar.</div><div class="htmlview paragraph">Drive cycle analysis over the WLTP was performed using these engine architectures, while assessing the sensitivity to various system parameters. These parameters include: vehicle weight and aerodynamic drag, EGR target maps, level of downspeeding, and turbocharger inertia. Vehicle performance and fuel economy was evaluated for the different boosting configurations to determine which vehicle design characteristics are complimented by the individual boosting configurations, and which are hindered. The simulation results demonstrate that the turbocharger-supercharger configuration provides benefits in both fuel economy and performance for all of the vehicle parameter variations studied. Specific trends between these benefits and each of the varied vehicle system parameters are presented as well.</div></div>

Abstract

Journal Article Alpine lyrics' Get access W. Nixon W. Nixon 1Heaton, Newcastle-on-Tyne Search for other works by this author on: Oxford Academic Google Scholar Notes and Queries, Volume s11-IV, Issue 80, 8 July 1911, Page 30, https://doi.org/10.1093/nq/s11-IV.80.30a Published: 08 July 1911