The agglomeration and growth of ash during regeneration of a diesel particulate filter was investigated through time-lapse visualization utilizing a field-emission scanning electron microscope and energy dispersive spectroscopy. The primary and large scale ash particles contain calcium, zinc, phosphorous and sulfur were dispersed in Particle Matters (PMs) cake layer. During the shrinkage of PMs Cake layer in regeneration, these ash components were gathered together to form various types of large agglomeration, as well as aggregation ash particles. They were nearly uniform deposited around the perimeters of surface pores.
Lead-acid battery is widely used as the electric power storage for automotive, industrial, forklift and golf cart application. Recently the new market needs are showing up such as Idling Stop Start (ISS) vehicle. Daramic is leading the development of novel lead-acid battery separator to meet the needs for ISS vehicle. This paper reports the key technical challenges and the innovations by novel lead-acid battery separator.
This research paper describes the effect of coil pitch on thermo-fluids characteristics of the spiral coil sub-cooled condenser. Primarily, the heat transfer results for channel size of 4.1 mm X 4.1 mm were experimentally found and validated with the CFD analysis. As the satisfactory agreements were obtained with smaller errors, the effect of the different coil pitch with the same height on the heat transfer has been examined by using the CFD analysis. Finally, the coil pitch with 6.2 mm leads to the higher velocity of secondary flow of 0.05 m/s, while 13.7mm pitch depicts the lower value of 0.03 m/s inside the square cross-section of the channel. Corresponding to the specific pitch sizes, the heat transfer coefficient depicts high value for the largest pitch size and least for the smallest pitch.
This current research work has been focused on Methane (CH4) reduction in a Diesel Oxidation Catalyst (DOC) emitted from a Dual Fuel-Premixed Charged Compression Ignition (DF-PCCI) engine. This new alternative combustion technology is implemented on a Diesel Engine powered by both diesel fuel and natural gas in order to reduce diesel fuel usage and maintain the same thermal efficiency. However, the drawback lies in higher amount of CH4 in the exhaust that might effects Original Equipment Manufacturer (OEM)’s DOC performance. In this work, thermophysical and chemical properties of DF-PCCI exhaust such as temperature, flow rate, and specie concentrations are varied to investigate their effects on CH4 conversion efficiency in DOC. Design of Experiment (DOE) is built and tested in a Synthetic Exhaust Gas Generating System that can simulate the DF-PCCI exhaust-like conditions and all tested parameters are fully controlled. The experimental matrix is selected to cover DF-PCCI exhaust condition ranges to optimizing CH4 treatment. A kinetic model with water concentration is also investigated and compared to DOE model and experimental data. It is shown that the major factors that influence methane oxidation are exhaust flow rate, H2O concentration, and exhaust temperature (at P-value < 0.05 or at confidence level of 95%). The DOE model for predicting CH4 reductions is also generated.
This paper presents a control design approach of efficiency optimization while providing the desired torque under the constraint of combustion variation for gasoline engines with EGR. Mainly, the first phase of control design is the equilibrium point optimization under the chance constraint of IMEP probability distribution with a scenario approach, and the second phase is nonlinear dynamic feedback stabilization control design for improving transient performance of the state regulation. The experimental validations demonstrate that the control scheme can achieve stable combustion and fast transient control performance.