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The purpose of this paper is to analyze and compare the performances of novel roadable personal air vehicle (PAV) concepts that meet established operational requirements with different types of engines.

The vehicle configuration was devised considering the dimensions and operational restrictions of the roads, runways and parking lots in South Korea. A folding wing design was adopted for road operations and parking. The propulsion designs considered herein use gasoline, diesel and hybrid architectures for longer-range missions. The sizing point of the roadable PAV that minimizes the wing area was selected, and the rate of climb, ground roll distance, cruise speed and service ceiling requirements were met. For various engine types and mission profiles, the performances of differently sized PAVs were compared with respect to the MTOW, wing area, wing span, thrust-to-weight ratio, wing loading, power-to-weight ratio, brake horsepower and fuel efficiency.

Unlike automobiles, the weight penalty of the hybrid system because of the additional electrical components reduced the fuel efficiency considerably. When the four engine types were compared, matching the total engine system weight, the internal combustion (IC) engine PAVs had better fuel efficiency rates than the hybrid powered PAVs. Finally, a gasoline-powered PAV configuration was selected as the final design because it had the lowest MTOW, despite its slightly worse fuel efficiency compared to that of the diesel-powered engine.

Although an electric aircraft powered only by batteries most capitalizes on the operating cost, noise and emissions benefits of electric propulsion, it also is most hampered by range limitations. Air traffic integration or any safety, and noise issues were not accounted in this study.

Aircraft sizing is a critical aspect of a system-level study because it is a prerequisite for most design and analysis activities, including those related to the internal layout as well as cost and system effectiveness analyses. The results of this study can be implemented to design a PAV.

This study can contribute to the establishment of innovative PAV concepts that can alleviate today’s transportation problems.

This study compared the sizing results of PAVs with hybrid engines with those having IC engines.

The aim of this paper is to find the optimal values of the reaction rates coefficients for the combustion of a methane/air mixture for a given reduced reaction mechanism which has a high appropriateness with full reaction mechanism.

A multi‐objective genetic algorithm (GA) was used to determine new reaction rate parameters (A's, β's, and E_a's in the non‐Arrhenius expressions). The employed multi‐objective structure of the GA allows for the incorporation of perfectly stirred reactor (PSR), laminar premixed flames, opposed flow diffusion flames, and homogeneous charge compression ignition (HCCI) engine data in the inversion process, thus enabling a greater confidence in the predictive capabilities of the reaction mechanisms obtained.

The results of this study demonstrate that the GA inversion process promises the ability to assess combustion behaviour for methane, where the reaction rate coefficients are not known. Moreover it is shown that GA can consider a confident method to be applied, straightforwardly, to the combustion chambers, in which complex reactions are occurred.

In this paper, GA is used in more complicated combustion models with fewer assumptions. Another consequence of this study is less CPU time in converging to final solutions.

The integrated course of study leading to an honours degree, which generally consists of alternate periods in college and in industry totalling four years, is more than a conventional three‐year full‐time course with a period of industrial training added. The significant difference is that in the integrated course a student is educated partly in an academic and partly in an industrial environment and these environments alternate throughout the student's educational development. This arrangement, which is particularly suited to the education of professional engineers, involves collaboration between the college and industry throughout a student's education and assumes that students work at university undergraduate level both in industry and in college.

This chapter provides an overview of the case and draws attention to the types of teams who respond to disasters, specifically a structure fire. We then provide a detailed recounting of the case, what resources were at play, and how the incident resolved.

There have been a number of case studies that have documented the challenges organizations face in monitoring complex and turbulent environments and the anomalous events that characterize them combined with multiteam systems’ unique combination of intricacy, propensity toward hazards, and necessary team cohesion makes it particularly difficult to foreshadow – and subsequently train for – all possible contingencies. The majority of the cases reported here is based on the official National Institute for Occupational Safety and Health report that occurred shortly after the event and which is a required investigation by both State and Federal laws. Although the report is publicly available, specific identifying information was removed to allow for ease of comparison and to emphasize the multiteam system processes of interest.

As outlined in the case study above, there are many challenges that were faced in this multiteam system response to the supermarket structure fire. We discuss the response of the multiteam systems and attempt to identify a few key areas where miss-steps occurred and how the response would be different when multiteam systems function properly. We conclude with some practical implications from the incident as well as how multiteam systems can be improved based on this case study.

This chapter provides a real-world example of a disaster and systematically analyzes the steps and decisions that were utilized during the process from a multiteam perspective. Hopefully, the analysis of the case presented here will assist in developing increased awareness during high-stress encounters and offer an unbiased evaluation of what is required to properly train and therefore mitigate such tragedies in the future.

The purpose of this paper is to study the fault diagnosis of internal combustion (IC) engine gearbox using vibration signals with signal processing and machine learning (ML) techniques.

Vibration signals from the gearbox are acquired for healthy and induced faulty conditions of the gear. In this study, 50% tooth fault and 100% tooth fault are chosen as gear faults in the driver gear. The acquired signals are processed and analyzed using signal processing and ML techniques.

The obtained results show that variation in the amplitude of the crankshaft rotational frequency (CRF) and gear mesh frequency (GMF) for different conditions of the gearbox with various load conditions. ML techniques were also employed in developing the fault diagnosis system using statistical features. J48 decision tree provides better classification accuracy about 85.1852% in identifying gearbox conditions.

The proposed approach can be used effectively for fault diagnosis of IC engine gearbox. Spectrum and continuous wavelet transform (CWT) provide better information about gear fault conditions using time–frequency characteristics.

In this paper, experiments are conducted on real-time running condition of IC engine gearbox while considering combustion. Eddy current dynamometer is attached to output shaft of the engine for applying load. Spectrum, cepstrum, short-time Fourier transform (STFT) and wavelet analysis are performed. Spectrum, cepstrum and CWT provide better information about gear fault conditions using time–frequency characteristics. ML techniques were used in analyzing classification accuracy of the experimental data to detect the gearbox conditions using various classifiers. Hence, these techniques can be used for detection of faults in the IC engine gearbox and other reciprocating/rotating machineries.

This paper seeks to evaluate the potential of heat exchanged aeroengines for future Unmanned Aerial Vehicle (UAV), helicopter, and aircraft propulsion, with emphasis placed on reduced emissions, lower fuel burn, and less noise.

Aeroengine performance analyses were carried out covering a wide range of parameters for more complex thermodynamic cycles. This led to the identification of major component features and the establishing of preconceptual aeroengine layout concepts for various types of recuperated and ICR variants.

Novel aeroengine architectures were identified for heat exchanged turboshaft, turboprop, and turbofan variants covering a wide range of applications. While conceptual in nature, the results of the analyses and design studies generally concluded that heat exchanged engines represent a viable solution to meet demanding defence and commercial aeropropulsion needs in the 2015‐2020 timeframe, but they would require extensive development.

As highlighted in Parts I and II, early development work was focused on the use of recuperation, but this is only practical with compressor pressure ratios up to about 10. For today's aeroengines with pressure ratios up to about 50, improvement in SFC can only be realised by incorporating intercooling and recuperation. The new aeroengine concepts presented are clearly in an embryonic stage, but these should enable gas turbine and heat exchanger specialists to advance the technology by conducting more in‐depth analytical and design studies to establish higher efficiency and “greener” gas turbine aviation propulsion systems.

It is recognised that meeting future environmental and economic requirements will have a profound effect on aeroengine design and operation, and near‐term efforts will be focused on improving conventional simple‐cycle engines. This paper has addressed the longer‐term potential of heat exchanged aeroengines and has discussed novel design concepts. A deployment strategy, aimed at gaining confidence with emphasis placed on assuring engine reliability, has been suggested, with the initial development and flight worthiness test of a small recuperated turboprop engine for UAVs, followed by a larger recuperated turboshaft engine for a military helicopter, and then advancement to a larger and far more complex ICR turbofan engine.

Nanoparticles have been studied as additives to lubrication oils for reducing friction and wear. The purpose of this paper is to investigate the effect of nanofluid on engine oil and friction reduction in a real engine.

The nanoparticles were prepared using a high‐temperature arc in a vacuum chamber to vaporize the Ti metal, and then condensed into a dispersant to form the TiO₂ nanofluid, which was used as lubricant additive. Experiments were performed in both real engine running and test rig.

It was found that the engine oil with nanofluid additive with an ethylene glycol dispersant of nanoparticles, had gelled after 10‐h of engine running. The problem of oil gelation (jelly‐like) was solved by replacing the dispersant with paraffin oil. The engine oil with TiO₂ nanoparticle additive exhibited lower friction force as compared to the original oil. The experiment showed that a smaller particle size exhibits better friction reduction with particle size ranging from 59 to 220 nm.

The paper is restricted to findings based on the dispersed nanoparticles in fluid as additive for engine lubrication oil.

The test results are useful for the application of nanofluid additive for engine oil.

Most previous researches in this field were executed on tribotester, rather than the actual engine. This paper describes experimental methods and equipment designed to investigate the application of TiO₂ nanofluid as lubricant additive in internal combustion engine.

The present work aims at improving the performance of the engine using optimized fuel injection strategies and operating parameters for plastic oil ethanol blends. To optimize and predict the engine injection and operational parameters, response surface methodology (RSM) and artificial neural networks (ANN) are used respectively.

The engine operating parameters such as load, compression ratio, injection timing and the injection pressure are taken as inputs whereas brake thermal efficiency (BTHE), brake-specific fuel consumption (BSFC), carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NO_x) and smoke emissions are treated as outputs. The experiments are designed according to the design of experiments, and optimization is carried out to find the optimum operational and injection parameters for plastic oil ethanol blends in the engine.

Optimum operational parameters of the engine when fuelled with plastic oil and ethanol blends are obtained at 8 kg of load, injection pressure of 257 bar, injection timing of 17° before top dead center and blend of 15%. The engine performance parameters obtained at optimum engine running conditions are BTHE 32.5%, BSFC 0.24 kg/kW.h, CO 0.057%, HC 10 ppm, NO_x 324.13 ppm and smoke 79.1%. The values predicted from ANN are found to be more close to experimental values when compared with the values of RSM.

In the present work, a comparative analysis is carried out on the prediction capabilities of ANN and RSM for variable compression ratio engine fuelled with ethanol blends of plastic oil. The error of prediction for ANN is less than 5% for all the responses such as BTHE, BSFC, CO and NO_x except for HC emission which is 12.8%.

This paper aims to present experimental results of gasoline-fuelled engine operation of a crankcase-scavenged two-stroke cycle engine used for unmanned air vehicle (UAV)/unmanned air system application and to cross correlate with computational fluid dynamic modelling results.

Computational modelling of the engine system was conducted using the WAVE software supported by the experimental research and development via dynamometer testing of a spark ignition UAV engine to construct a validated computational model exploring a range of fuel delivery options.

Experimental test data and computational simulation have allowed an assessment of the potential advantages of applying direct in-cylinder fuel injection.

The ability to increase system efficiency offers significant advantages in terms of maximising limited resources and extending mission duration capabilities. The computational simulation and validation via experimental test experience provides a means of assessment of possibilities that are costly to explore experimentally and offers added confidence to be able to investigate possibilities for the development of similar future engine designs.

The software code used has not been applied to such crankcase-scavenged two-stroke cycle engines and provides a valuable facility for further simulation of the twin cylinder horizontally opposed design to offer further system optimisation and exploration of future possibilities.

Automobiles have always been a major cause of air pollution. The vehicular emission contains several harmful pollutants that affect the surroundings and living beings. Mild CO exposure leads to headaches or unconsciousness. CO is also responsible for the global warming as well. CO is mainly generated in the IC engine due to incomplete combustion of the fuel. The purpose of this paper is to implement a CO absorption mechanism inside the exhaust pipe of vehicle.

In this research work the single cylinder four stroke spark-ignition engine is intended to run on petroleum and petroleum blended fuels. A new post-combustion emission control device called cobalt scrubber is employed to reduce the emission of CO during idling which absorb and later release it under transient conditions.

The emission of CO when the engine runs at petroleum is reduced from 6.24 to 3.02 per cent. Methanol 40 per cent+petrol 60 per cent gives a better emission result of 0.98 per cent of CO emission. So, the authors can implement the cobalt scrubber in automobiles to avoid CO emission during idling.

The scrubber clearly overcomes the drawbacks of the existing control techniques. The cobalt scrubber is a cheap, non-radioactive. It can be employed in any kind of vehicle irrespective of its engine.

The use of the scrubber design presented in this article, effectively reduces the emission of CO.