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Forty-nine plant-wide energy efficiency assessments have been undertaken under sponsorship of the U.S. Department of Energy's Industrial Technologies Program. Plant-wide assessments are comprehensive, systematic investigations of plant energy efficiency, including plant utility systems and process operations. Assessments in industrial facilities have highlighted opportunities for implementing best practices in industrial energy management, including the adoption of new, energy-efficient technologies and process and equipment improvements. Total annual savings opportunities of $201 million have been identified from the 40 completed assessments. Many of the participating industrial plants have implemented efficiency-improvement projects and already have realized total cost savings of more than $81 million annually. This paper provides an overview of the assessment efforts undertaken and presents a summary of the major energy and cost savings identified to date.

This paper presents a general method for measuring plant-wide industrial energy savings and demonstrates the method using a case study from an actual industrial energy assessment. The method uses regression models to characterize baseline energy use. It takes into account changes in weather and production, and can use sub-metered data or whole plant utility billing data. In addition to calculating overall savings, the method is also able to disaggregate savings into components, which provides additional insight into the effectiveness of the individual savings measures. Although the method incorporates search techniques and multi-variable least-squares regression, it is easily implemented using data analysis software. The case study compared expected, unadjusted and weather-adjusted savings from six recommendations to reduce fuel use. The study demonstrates the importance of adjusting for weather variation between the pre- and post-retrofit periods.

Advanced driving assistance systems and other applications to enhance car safety are well known and also well established in the automotive industry. These systems rely mostly on on-board sensors and data fusion algorithms which monitor the vehicle's environment. Another development is the concept of Car-to-Car Communications (C2CC) which can directly transmit the safety relevant data off-board to other vehicles. It can now be seen that both technology fields are growing together, but to make use of C2CC for sensor data fusion, there are many issues related to these topics that need to be solved. This paper highlights the advantages of a C2CC-enhanced sensor data fusion approach, as well as the associated challenges.

This paper investigates the chordal action and transmission errors of a simple silent chain system. The chordal action analysis is based on the tooth contact analysis of the chain with the driving sprocket. Chordal action of different contact patterns is compared. The result indicates that chordal action of the case in which at most two link pates are in contact is significantly reduced. The transmission error analysis is based the tooth contact analysis of the chain with both the driving and driven sprockets. The result shows how the angular motion of the driven sprocket deviates while the driving sprocket rotates at a constant speed.

For the better understanding of nanoparticles observed on the rode side, adding to the emission test on the chassis dynamometer and engine dynamometer test, possible factors for formation of nanoparticles are investigated. As other possible factors, cold starting of transient test cycle, blow-by gas from heavy duty diesel engine without a positive crankcase ventilation, exhaust braking, and plume mixing of vehicle exhausts were investigated. Nuclei mode particles under the transient test cycles formed during fuel cut period, fuel enrichment period and idling period. Concentration of nuclei mode particles during the idling period are depends on exhaust temperature. The higher exhaust temperature courses the lower number concentration but variation range is within twice. Emission rate of nanoparticles from blow-by gas is one thousandth of tail pipe emissions rate and was found to be negligible.

Pulsating flow is generated in a close-coupled catalyst exhaust manifold using a charged motored engine. Flow is very similar to fired engine conditions, featuring blow-down and displacement phases. Bidirectional time-resolved catalyst velocity distributions are measured using phase-locked oscillating hot-wire anemometry. Temporal and spatial occurrence of flow reversal through the catalyst is examined, and catalyst areas most subjected to backflow are identified. Mean catalyst velocity fluctuations are observed, caused by Helmholtz resonances in the manifold. These resonances are strong enough to induce flow reversal during the displacement phase. Reverse flow is considered important with respect to local thermal deactivation of the catalyst.

This paper investigates the effect of tailpipe orientation on carbon monoxide (CO) dispersion patterns which is directly linked to the CO exposure levels that a cyclist can experience in Oxford City. The most common tailpipe orientations used in Oxford city vehicles have been identified. Following this, the dispersion patterns from various tailpipe orientations were experimentally investigated and the results used to construct contour maps of CO dispersion patterns. The contour maps were used to estimate the likely exposure levels a cyclist can experience. The real-world cyclist CO exposure levels were also measured in two routes in Oxford city and compared with those obtained from the contour maps and data from fixed site monitoring station. The results show that CO levels in the cycle lane are significantly affected by the tailpipe orientation and are higher than the recommended World Health Organization (WHO) exposure levels.

A numerical simulation model for the prediction of fuel hydrocarbon permeation is presented in this work. The barrier layer thickness optimization for thermoplastic multilayer fuel tanks is also considered. The diffusion model is based on the continuum approach with steady-state permeation regime across the multilayer polymeric wall. The hydrocarbon flux through the multilayer wall is determined by assuming continuity in vapor pressure at the polymer-polymer interface. Since the pinch-off zone is known to be the major source of emission per unit area, a method has been developed to automatically detect this zone at the end of extrusion blow molding process. After then, an improvement to the diffusion model has been proposed in order to evaluate adequately the hydrocarbon permeation through this specific area. Finally, a gradient-based algorithm is applied to optimize the barrier layer thickness to satisfy the total hydrocarbon fuel emission constraint for a plastic fuel tank (PFT).

A major source of engine-off evaporative hydrocarbon emissions is fuel injector leakage. Methods and devices to relieve fuel rail pressure after key-off, and thus reduce leakage are introduced. Impact on fuel manifold re-pressurization is considered. The basic principles governing this behavior: fuel thermal expansion, fuel vapor pressure, and dissolved gasses in liquid are elaborated. Fuel pressure relief data is shown.

This paper presents a computational investigation of the effect of engine exhaust gas modulations on the performance of an automotive catalytic converter during cold starts. The objective is to assess if the modulations can result in faster catalyst light-off conditions and thus reduce cold-start emissions. The study employs a single-channel based, one-dimensional, non-adiabatic model. The modulations are generated by forcing the variations in exhaust gases air-fuel ratio and gas compositions. The results show that the imposed modulations cause a significant departure in the catalyst behavior from its steady behavior, and modulations have both favorable and harmful effects on pollutant conversion during the cold-starts. The operating conditions and the modulating gas composition have substantial influence on catalyst behavior.

By contribution of electronic technologies, the vehicle can achieve higher performance and safety. It is also an important measure to control emission level. However, it may cause an emission increase or sometimes dangerous driving conditions if electronic control system fails. That is the main reason that the OBD functions are occupied approximately 50% within an ECU logics. And, the importance of OBD test increases to ensure fulfillment of legislation requirement and quality to reduce the service and warranty costs. Especially, ETC (Electronic Throttle Control) system, which has many advantages on engine torque control flexibility but highly affects to the vehicle performance and safety controls. Therefore, it is an essential test procedure to verify the diagnosis and limp-home function for managing the possible all error cases.

Combustion feedback using cylinder pressure sensors, ion current sensors or alternative sensing techniques is actively under investigation by the automotive industry to meet future legislative emissions requirements. One of the drawbacks of many rapid prototyping engine management systems is their available analog interfaces, often limited to 10-12 bits with limited bandwidth, sampling rate and very simple anti-aliasing filters. Processing cylinder pressure or other combustion feedback sensors requires higher precision, wider bandwidths and more processing power than is typically available. For these reasons, Ricardo in collaboration with GM Research has developed a custom, high precision analog input subsystem for the rCube rapid prototyping control system that is specifically targeted at development of combustion feedback control systems.

Bringing a new automotive electronic control unit (ECU) to market is a multi-phase process. Generally speaking, the phases are engineering analysis, rapid prototyping, software implementation, test and calibration. A variety of engineering staff and tools are used as the ECU progresses through the development process. However, the use of different tools may require non-value-added steps to translate data and results from one process phase to another. This lack of integration introduces the potential for errors, adds delay and costs to projects, and makes it difficult to trace the behavior of the final product back to the original requirements. Model-Based Design addresses many of the integration problems through use of executable specification models and automatic code generation. However, connecting the design effectively to the prototype vehicle provides additional integration challenges since it requires specialized hardware interfaces and target-specific software device drivers.

A main focus of development in modern SI engine technology is variable valve timing, which implies a high potential of improvement regarding fuel consumption and emissions. Variable opening, period and lift of inlet and outlet valves enable numerous possibilities to alter gas exchange and combustion. However, this additional variability generates special demands on the calibration process of specific engine control devices, particularly under cold start and warm-up conditions. This paper presents procedures, based on Hardware-in-the-Loop (HiL) simulation, to support the classical calibration task efficiently. An existing approach is extended, such that a virtual combustion engine is available including additional valve timing variability. Engine models based purely on physical first principles are often not capable of real time execution. However, the definition of initial parameters for the ECU requires a model with both real time capability and sufficient accuracy.

In order to reduce engine control strategy development time and cost, the Hardware-In-the-Loop (HIL) simulation technology is developed. This paper establishes a simulation model and control platform based on the HIL structure for studying control strategy development and verification. A 125c.c. engine model verified by the experimental data is established in Matlab/Simulink, which is used as a virtual engine and then implemented in the xPC real-time system. The Motorola MC 68376 controller chip provides control signals included injection duration/timing and ignition timing for the virtual engine. A PCI-6024E input/output board is used as an interface between the controller and the virtual engine. A simulation model, which consists of engine, powertrain, tire, and pitch plane dynamics, is used to evaluate the response of engine dynamics and longitudinal dynamics via HIL simulation.

Noise and vibration are critical to a customer’s overall positive or negative perception of passenger cars. Increasing market demands regarding comfort mean that a vehicle’s acoustic features must demonstrate continuous improvement to remain competitive. In the new model car, the influence of vibration excitation (caused by force) and noise transfer (transfer functions) of suspension should be investigated by considering the three dimensions of noise behavior of the vehicle. Measurement under real operating conditions using a servo-hydraulic multi-channel test rig was chosen. The level of the excitation was chosen in such a way that the coherence on the response signals was mostly above 90%. It was found that noise sensitivity of the upper transfer path (piston rod - upper mount - body – interior) is distinctly higher than the lower transfer path (shock absorber tube - lower mount - wheel carrier - chassis - body – interior).

Electro-Rheological (ER) and Magneto-Rheological (MR) fluid based advanced suspension dampers are emerging to be the next generation of suspension dampers for their attractive features and promising performance potential to overcome the limitations of existing dampers in market. This study compares the vibration and shock isolation performances of ER damper and MR damper with linear passive damper and two-stage asymmetric non-linear damper using a four degrees-of-freedom pitch plane ride model. The study reveals superior vibration and shock isolation performance of ER and MR dampers for sprung mass compared to linear passive and asymmetric non-linear dampers. At higher frequencies (above 10 Hz), these dampers transmit higher load to pavement compared to other two. The study suggests that asymmetricity should be included in the design of these dampers to achieve improved performance over the entire frequency range.

Surround sound provided by stereo and 5.1 systems may not be satisfying all its listeners. Whether in the automobile or in the home, customers complain of “nothing from the rear speakers”, or about the sound “not filing the room”, etc. While 5.1 systems promise more surround, the economics of music production and concerns of music professionals are likely causing stereo to dominate production resources and causing 5.1 mixes to miss their full potential. The author believes that post-processing electronic and acoustic manipulation can produce sound that customers will prefer. A controlled experiment was performed which compared reference stereo and surround systems to ones augmented by extra surround equipment.

This work demonstrates a practical method for predicting vehicle-level automotive steering system NVH performance from component-level NVH measurements of hydraulic steering pumps. For this method, in-vehicle measurements were completed to quantify vehicle noise path characteristics, including steering system structure borne, fluid borne and airborne paths. At the component level, measurements of steering pump reaction forces, sound power and dynamic hydraulic pressure were also completed. The vehicle-level measurement data was used to construct NVH transfer functions for the vehicle. These transfer functions were in turn combined with the pump component data measured on a test stand to create a prediction for steering pump order vehicle interior noise. The accuracy of these predicted values was assessed through comparison with actual vehicle interior noise measurements.

Although automotive audio systems are getting increasingly sophisticated, cooling strategies are still primarily heat sink based. This paper describes the integration of a heat pipe into automotive radios in order to manage the heat in an effective manner. The heat pipe system proposed in this paper enables the heat produced by the devices to move and dissipate at a location outside of radio casing. The effectiveness of the system is validated experimentally by operating the radio with and without the heat pipe in a controlled environment and comparing the CD/media temperature in each case. It was found that heat pipe can be very effective not only in reducing the heat sink temperature, but also the media temperature.