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The motivation of the present work was to understand the mechanism by which alcohols produce less aromatic species in their combustion process than an equal amount of hydrocarbon with similar molecular structure does. Due to its numerous advantages over short-chain alcohols, butanol has been considered very promising in soot reduction. Excluding the influence of spray, vaporization and mixing process in engine cases, an adiabatic constant-pressure reactor model was applied to investigate the effect of butanol additives on aromatic species, which are known to be soot precursors, in fuel-rich butane flames. To keep the carbon flux constant, 5% and 10% oxygen by mass of the fuel were added to butane using butanol additive, respectively. Based on the soot reduction effects proposed in literature, effects on temperature, key radical concentrations and the carbon removal from the pathway to aromatic species were considered to identify the major mechanism of reduction in aromatic species.

With the development of advanced ABE fermentation technology, the volumetric percentage of acetone, butanol and ethanol in the bio-solvents can be precisely controlled. To seek for an optimized volumetric ratio for ABE-diesel blends, the previous work in our team has experimentally investigated and analyzed the combustion features of ABE-diesel blends with different volumetric ratio (A: B: E: 6:3:1; 3:6:1; 0:10:0, vol. %) in a constant volume chamber. It was found that an increased amount of acetone would lead to a significant advancement of combustion phasing whereas butanol would compensate the advancing effect. Both spray dynamic and chemistry reaction dynamic are of great importance in explaining the unique combustion characteristic of ABE-diesel blend. In this study, a semi-detailed chemical mechanism is constructed and used to model ABE-diesel spray combustion in a constant volume chamber.

Artificial ice shapes of various geometric fidelity were tested on a wing model based on the Common Research Model. Low Reynolds number tests were conducted at Wichita State University’s Walter H. Beech Memorial Wind Tunnel utilizing an 8.9% scale model, and high Reynolds number tests were conducted at ONERA’s F1 wind tunnel utilizing a 13.3% scale model. Several identical geometrically-scaled ice shapes were tested at both facilities, and the results were compared at overlapping Reynolds and Mach numbers. This was to ensure that the results and trends observed at low Reynolds number could be applied and continued to high, near-flight Reynolds number. The data from Wichita State University and ONERA F1 agreed well at matched Reynolds and Mach numbers. The lift and pitching moment curves agreed very well for most configurations.

Local nonlinearities can affect the global dynamics of their linear host structures. In the context of fixed-wing aircraft, failure of store mounting can result in strong local nonlinearities. In this work, we experimentally mimic store mounting failure conditions in a model airplane subject to harmonic excitation. Two identical stores are mounted under the wings and are placed symmetrically opposite each other. The configuration where both stores are “locked”, i.e., mounting is very stiff, serves as the baseline linear system. The second configuration involves unlocking one of the stores, enabling a geometrically nonlinear flexure connection between the unlocked store and the wing. The flexure lets the store interact with the first flexible mode of the airplane, resulting in large relative displacements between the store and wing. In addition, the configuration allows for vibro-impacts between the wing and store.

The paper presents a semi-empirical model to predict refrigerant and lubricant inventory in both evaporator and condenser of an automotive air conditioning (MAC) system. In the model, heat exchanger is discretized into small volumes. Temperature, pressure and mass inventory are calculated by applying heat transfer, pressure drop and void fraction correlations to these volumes respectively. Refrigerant and lubricant are treated as a zeotropic mixture with a temperature glide. As refrigerant evaporates or condenses, thermophysical properties are evaluated accordingly with the change of lubricant concentration. Experimental data is used to validate the model. As a result, refrigerant and lubricant mass is predicted within 20% in the evaporator. However, in the condenser, lubricant mass was consistently under-predicted while refrigerant mass was predicted within 15% error. Moreover, the lubricant under-prediction becomes more significant at higher Oil Circulation Ratio (OCR).

This paper reports a meta analysis of all studies located in the literature that have compared head up versus head down display of equivalent information, as these displays support both tracking (e.g., flight path control) and discrete event detection. The data clearly indicate a HUD advantage for most tasks, except tracking during cruise flight and event detection during final approach. The latter HUD cost however is observed only when events to be detected are entirely unexpected, reflecting a form of cognitive tunneling. The meta-analysis also reveals an advantage for conformal over non-conformal HUD imagery.

Ejector as a work recovery device offers potential for developing energy efficient heating and cooling systems based on vapor compression technology. For applications like automobile air conditioning, the operating conditions vary significantly which can lead to considerable performance degradation when the system is operated in off-design conditions. Therefore, system designing warrants development of accurate ejector performance models for a wide range of operating conditions. In this paper, a novel methodology for ejector performance maps is proposed using ejector efficiency as performance parameter and volumetric entrainment ratio as characterization parameter. The proposed performance map is developed after conducting experiments to find appropriate performance representation where ejector driven flow can be characterized using ejector motive flow. The developed performance map can predict ejector pressure lift within an accuracy of 20% using an iterative solver.

Due to the increasing consumption of fossil fuels, alternative fuels in internal combustion engines have attracted a lot of attention in recent years. Ethanol is the most common alternative fuel used in spark ignition (SI) engines due to its advantages of biodegradability, positively impacting emissions reduction as well as octane number improvement. Meanwhile, acetone is well-known as one of the industrial waste solvents for synthetic fibers and most plastic materials. In comparison to ethanol, acetone has a number of more desirable properties for being a viable alternative fuel such as its higher energy density, heating value and volatility.

The effect of lubricant on distribution is investigated by relating the flow regime in the horizontal inlet header and the corresponding infrared image of the evaporator. Visualization of the flow regime is performed by high-speed camera. R134a is used as the refrigerant with PAG 46 as lubricant, forming foam in all flow regimes. Quantitative information including foam location, foam layer thickness is obtained using a matlab-based video processing program. Oil circulation rate effect on flow regime is analyzed quantitatively.

HTL is a kind of biodiesel converted from wet biowaste via hydrothermal liquefaction (HTL), which has drawn increasing attention in recent years due to its wide range of raw materials (algae, swine manure, and food processing waste). However, from the previous experiments done in a constant volume chamber, it was observed that the presence of 20% of HTL in the blend produced as much soot as pure diesel at in chamber environment oxygen ratio of 21%, and even more soot at low oxygen ratios. It was also observed that n-butanol addition could reduce the soot emission of diesel significantly under all tested conditions. In this work, the spray and combustion characteristics of HTL and diesel blends with n-butanol added were investigated in a constant volume chamber. The in-chamber temperature and oxygen ranged from 800 to 1200 K and 21% to 13%, respectively, covering both conventional and low-temperature combustion (LTC) regimes.

A new Aircraft Accident Awareness Program (AAAP) was developed, evaluated, and is available to emergency response service provider organizations (firefighters, emergency medical technicians, trauma center personnel, law enforcement, clergy, coroners, and media) who would be called to an aircraft accident scene. Aircraft accident responder training is a critical factor in accident victim crash survivability and successful life-safety outcomes. This program was designed to teach participants about the unique conditions and safety hazards associated with aircraft crashes. A blend of academic classroom investigation, exposure to airworthy/ unairworthy aircraft including operating systems and components, computer accident simulations, “hands-on” (destructive) extrication protocol training, and participation in simulated in-the-field accident scenarios was used as an instructional delivery model.

Using neural networks, an algorithm has been developed to steer a wheel loader vehicle. Mathematical functions have been used in the past in an attempt to model a human in their operation of many types of vehicles. Since such functions can typically only be derived for situations in which the problem domain is thoroughly understood, research continues in an effort to develop a complete “operator model”. Neural Network algorithms were utilized in an attempt to determine the feasibility of accurately modeling the operator of a wheel loader construction vehicle. These algorithms were also used to determine how the control of different vehicle functions might be automated on a wheel loader.

This research compares the responses of a vehicle modeled in the 3D vehicle simulation program SIMON in the HVE simulation operating system against instrumented responses of a 3-axle tractor, 2-axle semi-trailer combination. The instrumented tests were previously described in SAE 2001-01-0139 and SAE 2003-01-1324 as part of a continuous research effort in the area of vehicle dynamics undertaken at the Vehicle Research and Test Center (VRTC). The vehicle inertial and mechanical parameters were measured at the University of Michigan Transportation Research Institute (UMTRI). The tire data was provided by Smithers Scientific Services, Inc. and UMTRI. The series of tests discussed herein compares the modeled and instrumented vehicle responses during quasi-steady state, steady state and transient handling maneuvers, producing lateral accelerations ranging nominally from 0.05 to 0.5 G's.

Aerodynamic assessment of icing effects on swept wings is an important component of a larger effort to improve three-dimensional icing simulation capabilities. An understanding of ice-shape geometric fidelity and Reynolds and Mach number effects on iced-wing aerodynamics is needed to guide the development and validation of ice-accretion simulation tools. To this end, wind-tunnel testing was carried out for 8.9% and 13.3% scale semispan wing models based upon the Common Research Model airplane configuration. Various levels of geometric fidelity of an artificial ice shape representing a realistic glaze-ice accretion on a swept wing were investigated. The highest fidelity artificial ice shape reproduced all of the three-dimensional features associated with the glaze ice accretion. The lowest fidelity artificial ice shapes were simple, spanwise-varying horn ice geometries intended to represent the maximum ice thickness on the wing upper surface.

Understanding the aerodynamic impact of swept-wing ice accretions is a crucial component of the design of modern aircraft. Computer-simulation tools are commonly used to approximate ice shapes, so the necessary level of detail or fidelity of those simulated ice shapes must be understood relative to high-fidelity representations of the ice. Previous tests were performed in the NASA Icing Research Tunnel to acquire high-fidelity ice shapes. From this database, full-span artificial ice shapes were designed and manufactured for both an 8.9%-scale and 13.3%-scale semispan wing model of the CRM65 which has been established as the full-scale baseline for this swept-wing project. These models were tested in the Walter H. Beech wind tunnel at Wichita State University and at the ONERA F1 facility, respectively. The data collected in the Wichita St.

This paper presents the experimentally obtained performance characteristics of an air conditioning-heat pump system that uses heat exchangers from a commercially available Nissan Leaf EV. It was found that refrigerant charge needed for cooling operation was larger than that for heating function with the test setup. The effects of: a). indoor air flow rate, b). outdoor air flow rate, and c). compressor speed on heating capacity and energy efficiency were explored and presented. Appropriate opening size of expansion valve that controlled subcooling for better energy efficiency was discussed and results were presented. Expansion valve opening size also strongly affected charge migration. Warm-up tests at different ambient conditions showed the necessity of a secondary heater to be reserved for very low ambient temperature.

This paper develops a model for a parallel microchannel evaporator that incorporates quality variation at the tube inlets and variable mass flow rates among tubes. The flow distribution is based on the equal pressure drop along each flow path containing headers and tubes. The prediction of pressure drop, cooling capacity, and exit superheat strongly agree with 48 different experimental results obtained in four configurations using R134a. Predicted temperature profiles are very close to infrared images of actual evaporator surface. When compared to the uniform distribution model (that assumes uniform distribution of refrigerant mass flow rate and quality) results from the new model indicate superior prediction of cooling capacity, and exit superheat. Model results indicate maldistribution of refrigerant mass flow rate among the parallel tubes, caused primarily by pressure drop in the outlet header.

Six, one hundred eighty horsepower aircraft piston engines have been operated through their normal overhaul life using three different ashless dispersant multi-viscosity aircraft oils. Two of these oils achieved their multi-viscosity characteristics by utilizing some synthetic base stock while the third utilized additional viscosity-index (V-I) improver. The performance of these three oils was compared with that of a conventional, single-grade AD oil in six identical control aircraft engines. The results of this test indicates that multi-viscosity oils provide improved cold-weather starting, less consumption, and comparable wear rates to the six control engines.

Air source heat pumps as the heating system for full electric vehicles are drawing more and more attention in recent years. Despite the high energy efficiency, frost accumulation on the heat pump evaporator is one of the major challenges associated with air source heat pumps. The evaporator needs to be actively defrosted periodically and heat pump heating will be interrupted during defrosting process. Proper defrost control is needed to obtain high average heat pump energy efficiency. In this paper, a new method for generating air source heat pump defrost control policy using reinforcement learning is introduced. This model-free method has several advantages. It can automatically generate optimal defrost control policy instead of requiring manually determination of the control policy parameters and logics.

As international markets and competitiveness gain importance in the automobile industry, interest in the issue of standards harmonization is growing. Currently, the main efforts aimed at harmonizing standards are run through the Economic Commission for Europe (ECE). One major area of ongoing progress is safety standard harmonization. One main conflict affecting resolution of this issue is the fundamental difference in regulation administration between the United States, Europe, and Japan for safety standards. Of these regions, Europe and Japan follow type approval methods, while the United States adheres to self-certification. This difference bars the United States from participating in efforts to develop a globally accepted type approval system. Key policy alternatives presented are the continuation of U.S. support for current harmonization efforts, the worldwide acceptance of one set of already-existing regulations, and non-harmonization.