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Metal fiber DPF system is cheaper and more endurable than ceramic filter; however, the regeneration near the wall (outer layer) is difficult because of the heat loss and the less gas flow rate near the wall. In this study, a 3D CFD simulation is performed to find the flow control method for the more uniform mass flux for all filter layer. The major control factors are filter porosity, distribution plate and swirler. By placing the distribution plate in front of the filter the flow near the wall can be increased. The optimum place and size was chosen. The swirler can increase the flow more near the wall.

Abstract Composite ceramic brake discs are made of ceramic material reinforced with carbon fibers and offer exceptional advantages that translate directly into higher vehicle performance. In the case of an electric vehicle, it could increase the range of the vehicle, and in the case of conventional internal combustion engine vehicles, it means lower fuel consumption (and consequently lower CO2 emissions). These discs are typically characterized by complex internal geometries, further complicated by the presence of drilling holes on both friction surfaces. To estimate the aerothermal performance of these discs, and for the thermal management of the vehicle, a reliable model for predicting the air flowing across the disc channels is needed. In this study, a real carbon-ceramic brake disc with drilling holes was investigated in a dedicated test rig simulating the wheel corner flow conditions experimentally using the particle image velocimetry technique and numerically.

Automotive friction materials are composites containing three kinds of components: an organic binder, fiber for reinforcement, and property modifiers. At low braking temperatures, the wear rate of the friction materials is controlled primarily by abrasive and adhesive mechanisms. At higher braking temperatures, the wear rate increases exponentially with increasing temperature due to thermal degradation of the binder and other components, and the exponential wear rate is frequently accompanied by brake fade. Thus, one method of reducing thermal wear and fade tendency is to lower the temperature at the rotor/friction material interface. Since the rate of heat transfer from the interface is mostly dependent upon the conductive and convective modes, a rotor of high thermal conductivity will have a significant advantage over a rotor of low conductivity, if the heat capacity remains the same.

Weight reduction is a primary concern in the design of today's automobiles. Fiber reinforced composites (FRC) comprise a category of materials that may offer advantages in terms of weight and cost when compared to both steel and aluminum. The viability of low cost FRCs such as a glass fiber reinforced plastic (GFRP) as a structural material for automotive applications can, however, be diminished by functional requirements such as energy absorption and crush under impact loading. In this context, the crash safety performance of front rails of a compact passenger car is evaluated by assuming these to be made of GFRPs with constant strand mat (CSM) plies. The safety assessment of rails is carried out with the aid of the explicit nonlinear finite element analysis code LS-DYNA with utmost attention being paid to the proper constitutive modeling of the composites considered.

Chopped carbon fiber sheet molding compound (SMC) material is a promising material for mass-production lightweight vehicle components. However, the experimental characterization of SMC material property is a challenging task and needs to be further investigated. There now exist two ASTM standards (ASTM D7078/D7078M and ASTM D5379/D5379M) for characterizing the shear properties of composite materials. However, it is still not clear which standard is more suitable for SMC material characterization. In this work, a comparative study is conducted by performing two independent Digital Image Correlation (DIC) shear tests following the two standards, respectively. The results show that ASTM D5379/D5379M is not appropriate for testing SMC materials. Moreover, the failure mode of these samples indicates that the failure is caused by the additional moment raised by the improper design of the fixture.

To advance vehicle lightweighting, chopped carbon fiber sheet molding compound (SMC) is identified as a promising material to replace metals. However, there are no effective tools and methods to predict the mechanical property of the chopped carbon fiber SMC due to the high complexity in microstructure features and the anisotropic properties. In this paper, a Representative Volume Element (RVE) approach is used to model the SMC microstructure. Two modeling methods, the Voronoi diagram-based method and the chip packing method, are developed to populate the RVE. The elastic moduli of the RVE are calculated and the two methods are compared with experimental tensile test conduct using Digital Image Correlation (DIC). Furthermore, the advantages and shortcomings of these two methods are discussed in terms of the required input information and the convenience of use in the integrated processing-microstructure-property analysis.

Acoustical materials are widely used in automotive vehicles and other industrial applications. Two important parameters namely Sound Transmission Loss (STL) and absorption coefficient are commonly used to evaluate the acoustical performance of these materials. Other parameters, such as insertion loss, noise reduction, and loss factors are also used to judge their performance depending on the application of these materials. A systematic comparative study of STL and absorption coefficient was conducted on various porous acoustical materials. Several dozen materials including needled cotton fiber (shoddy) and foam materials with or without barrier/scrim were investigated. The results of STL and absorption coefficient are presented and compared. As expected, it was found that most of materials are either good in STL or good in absorption. However, some combinations can achieve a balance of performance in both categories.

This paper focuses on the energy absorbing characteristics and progressive deformation behavior of woven jute-polyester composite cylindrical tubes subjected to an axial impact load. In this study, the impact energy absorption characteristics and crushing mechanisms of composite tubes of different thicknesses and number of plies are investigated. To start with, coupon specimens are made from laminates of jute and glass fiber-based polyester composites. These are then tested in a UTM for mechanical characterization of the composites under tensile and compressive loading conditions. Experiments are then conducted in a drop-weight impact testing device to investigate crash performance characteristics such as mean crush load, absorbed energy and specific energy absorption (SEA) of woven jute-polyester composite cylindrical tubes.

Identical fiber wheel liners were installed on two different mid size vehicles in order to compare the noise reduction for each vehicle. The fiber liners represented material in current production. A baseline noise level was established with the existing plastic wheel liners and then comparisons were made with fiber wheel liners. Noise levels were compared in the wheel well and in the interior for similar vehicle operating conditions. For both vehicles, significant tire noise reduction at the source was measured with fiber liners compared to plastic liners. One of the vehicles also demonstrated noise reduction in the passenger cabin with fiber liners. Insight into potential explanations for these differences was provided by comparing the noise levels at different locations within the vehicles. The results show how fiber liners are an additional tool to reduce the noise in a vehicle and how the NVH design for the balance of the vehicle can leverage the NVH impact of these parts.

The thermo-oxidative stability of various commercial graphite fibers was determined at 316°C (600°F) for over 4000 hours. In addition, to understand how graphite fiber surface properties affect thermo-oxidative stability of high temperature polymer composites containing these fibers, the surfaces were analyzed by electron spectroscopy for chemical analysis. The fiber systems studied were Celion 6000, G40-700, T-40R, IM6, AS4 and T-300R. The thermo-oxidative stability of T-40R and G40-700 was found to be superior to Celion 6000, T-300R and AS4. This improved stability of T-40R and G40-700 was found to be related to the carbon, oxygen and nitrogen concentrations. These fiber surfaces contained higher carbon contents and much lower concentrations of oxygen and nitrogen than the other fibers.

In an earlier paper, a series of comparison tests were described that verified the cost/performance advantage of die-cast zinc over five unreinforced, engineering thermoplastics in tension, flexure, creep, impact, and fatigue when compared under identical test procedures and specimen geometries as dictated by plastics industry standards. Additional tests showed the superiority of die-cast zinc over these same thermoplastics in regard to thread strength, dimensional stability, heat distortion, weathering, flammability, and chemical stress cracking. This paper reports on a continuation of these same series of test procedures where die-cast zinc is compared with six 40% glass-reinforced thermoplastics. Again the results continue to show the cost/performance superiority of die-cast zinc over the reinforced thermoplastics tested.

Gas-permeable membranes that continuously transfer carbon dioxide (CO2) from air to water were investigated in an effort to bypass the operational limitations of expendable solid absorbents currently used for CO2 control in closed-circuit underwater breathing apparatus (UBA). Rebreather UBA CO2 control requirements and known membrane properties were used to create a functional hierarchy of membrane types and CO2 transfer mechanisms, from which one membrane configuration was selected for evaluation. This Direct Contact Membrane Separator (DCMS) employs microporous hydrophobic Hollow Fiber Membrane (HFM) modules to create large membrane areas in small volumes for air-water phase contact without intermixing. Since the micropores in the hydrophobic walls of the hollow fibers are air-filled, gas permeation rates through this membrane are far higher than for any solid or liquid membrane.

In a fastening system when there is a small misalignment of the holes, the holes are enlarged to align the axes and a next size fastener is used to fit the joint. But when the misalignment is large then the enlargement need to be proportionally large. In this case a bushing is press fit onto the hole to handle the fastening. If we press fit a bushing, it generates residual stresses in the panel. These residual stresses reduce the damage life of the components on which the bushings were press fit. In the aircraft engine nacelle components the damage life is very critical in various failure conditions such as fan blade out condition, wind milling and bird strike. It increases the flight time in these events. Here four different case studies were considered to study the damage life of the aircraft components made of Aluminum or composite material.

The automobile industry is seeing an increased need for the application of plastics and their derivatives in various forms such as fiber reinforced plastics, in the design and manufacture of various automotive structural components, to reduce weight, cost and improve fuel efficiency. A lot of effort is being directed at the development of structural plastics, to meet specific automotive requirements such as stiffness, safety, strength, durability and environmental standards and recyclability. This paper presents the concept of reinforcing large injection molded fiber reinforced body panels with structural uni-directional fibers (carbon, graphite, kevlar or fiber glass) wound in tension around the body panels by filament winding technique. Structural uni-directional fibers in tension wound around the fiber reinforced plastic inner body panels would place these body panels under compression.

This document establishes training guidelines applicable to fiber optic fabricator technical training for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Production

This document establishes training guidelines applicable to fiber optic safety training, technical training and fiber awareness for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems.

This document establishes training guidelines applicable to fiber optic safety training, technical training and fiber awareness for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Logisticians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Shipping Receiving Production Purchasing

This document establishes training guidelines applicable to fiber optic installer technical training for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Logisticians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Shipping Receiving Production Purchasing

This document establishes training guidelines applicable to fiber optic installer technical training for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Logisticians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Shipping Receiving Production Purchasing

This document establishes training guidelines applicable to fiber optic technician, quality assurance, or engineer technical training for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Production