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Small, turbine-powered eAPUs (electric Auxiliary Power Unit) have poor off-design performance and efficiency. Turbo eAPUs remain competitive where efficiency is sacrificed to lightness and compactness. The first part of this paper summarizes the transformation of a very efficient, very large automotive turbocharger into an eAPU. A satisfactory solution for the design of the heavy fuel combustor has been found on the Giandomenico’s site. The performance of the APU is evaluated at the Garrett nominal air conditions (T0=302.6 K, p0=0.962 bar, dry air). The turbogas has an approximately linear braking torque from 50% to 100% load at nearly maximum efficiency. Below 50% load, it is more convenient to vary the maximum temperature of the cycle and adjust the generator torque. However, a better compromise can be obtained by coupling the APU with a battery that would supply the electric power under 50% load. The use of a recuperator is not convenient due to the increase in volume and the additional complication. The problem of the intake air filtering is particularly serious in dirty/sandy ground applications. Regarding efficiency, the turbogas is no match for the diesel eAPUs.

A feasibility study for the installation of a CRDID (Common Rail Direct Injection Diesel) on a light helicopter is introduced. The total mass available for the CRDID is evaluated starting from fuel consumption and helicopter data. The conversion of an automotive unit was discarded to excessive mass and excessive costs of the conversion. A derivative of an automotive engine was then considered. This solution proved to be feasible. The installation of the new CRDID was then studied. The turbocharger and the cooling system were defined for the application. The result was the evaluation of the power plant installation mass that proved to be much lower than the maximum admissible. The installation is then possible. La Se presenta un estudio de factibilidad para la instalación de un CRDID ( Common Rail Direct Injection Diesel por sus siglas en ingles) en un helicóptero ligero . La masa total disponible para el CRDID se calcula a partir de los datos de consumo de combustible y datos de helicópteros. La conversión de una unidad de automoción se descartó debido a los costos excesivos en masa, y costos excesivos en conversión. A continuación se considera un derivado de un motor de automóvil . Esta solución ha demostrado ser factible. Posteriormente, se estudió la instalación de la nueva CRDID . El sistema de refrigeración y el turbocompresor se definieron para la aplicación. El resultado fue el calculo de la masa de instalación de la planta de energía que resultó ser mucho menor que el máximo admisible. La instalación es entonces realizable.

The large majority of current trainers are piston engine aircrafts. Their engine lasts 2,000 hours maximum. The idea is to substitute the engine with a green electric powerpack with the same performance of the original unit, but with no emission and basically with no maintenance. The powerpack should be easy to install, safe and should provide sufficient autonomy. This last part is particularly easy for trainers, since they fly in a very standard way. At morning, with the battery fully charged, the instructor and the student perform a flight that lasts typically from 20 minutes to 2 hours. On landing a de-briefing of the student takes place. This phase is followed by the briefing of the new student. These two steps take at minimum of 30 minutes. During this time the battery can be partially recharged. The process will continue for a full day, with a longer recharge during break times. Therefore, it is perfectly possible to have a one day autonomy (about 10 hours). This project is intended to develop an experimental green trainer to validate the best configuration for this power pack and to find-out critical issues on installation, safety, reliability and maintenance. Finally, a minimum number of 300 hours of flight will be performed to perform an accelerated test to individuate critical safety issues on the new proposal. This part should be considered as in integral part of the University Career for those aviation students who want to get involved in testing and engineering, rather than only flying. At the same time, converting powerplants from the combustion ones into the electric ones will contribute to reduce the polluting emissions in the air that produce micro-climate changes.

Material behavior depends on average peak temperature, stress magnitude and stress gradient. This assumption is valid since temperatures varies slowly when compared to pressure (stress). In this paper, a RR Merlin head is simulated with a few mathematical models used in Formula 1 racing. These extremely simplified models make it possible to evaluate temperatures and pressures starting from very few data. The method is described in detail, along with the many experimental coefficients available from several years of design activity. A step by step approach is used to allow the comprehension of this method that was developed by the Authors. The choice of the RR Merlin was dictated by the public availability of experimental data on temperatures. In fact, in the case of the RR Merlin XX, very reliable experimental results are available in NACA TN 2069. A reverse engineering process was applied on a rescued RR Merlin XX head. An accurate redesign was performed to obtain a 3D model. Assembly instructions and tolerances were found on original Rolls Royce overhaul manuals. In this way assembly and working loads were calculated and simulated. Nonlinear FEA analysis was performed on this CAD model with extremely satisfactory results for the thermal loads. Well known criticalities of the original design were found. The results were compared with NACA results both for heat rejection and temperatures. However, the mechanical stresses proved to be more critical for simulation and evaluation. Therefore, they will be discussed in another, dedicated paper.

This paper introduces a method to efficiently monitor the status of a piston engine during flight. ECUs (Electronic Control Units) make it possible to fly safely without emergencies or urgencies with random electronic failures of components and connections. The same can be easily done on older engines by adding a reliable digital monitoring system and an automated calibration of the carburetors. In fact, their reliability is several order of magnitude inferior to modern turboshafts. In modern engines with FADEC (Full Authority Digital Electronic Control) as the “on” button is pressed the sensors and actuators are checked. The CPUs will then run start-up during the cranking phase (engine running without ignition). If everything is all right, then the engine starts and the post start checks are also performed. During flight, the ECU checks CPUs, sensors and actuators. Therefore, the electronic system can be monitored with high reliability without much effort. The sensors may crosscheck the engine situation and may output very reliable early diagnosis of incoming failures. Statistical data on spare parts are invaluable for monitoring application, signaling weak or not-lasting components and failure modes. This is another advantage of automotive piston engines conversions to aircraft use.

Multiple-speed gearboxes with computer controlled automatic gear selection devices are a common possible choice in cars. Robotized gear insertion of one tenth of a second is possible. Economical and weight consideration are to be made to verify if it is convenient to use a smaller engine and a larger gearbox with a wider choice of speeds. In this paper, an automotive application for a public transport vehicle based on a Class S chassis with the choice of common-rail direct injection engines. This choice is particular unfavorable for the multispeed gearbox since common-rail engines have very flat specific fuel consumption curves. The lumped mass model implemented is conceived to estimate velocity, acceleration and fuel consumption starting from aerodynamic, inertia and thermodynamic data of the vehicle. The estimated data of performance and fuel consumption were compared with measured values. A Genetic elitarian Algorithm (GA) was used to optimise the engine choice and the gearbox speeds distribution. A maximum reduction of 15% was then calculated with a 16-speeds gearbox and a 140 HP/300Nm engine in comparison with the standard 5-speeds 204 HP/500Nm engine. This fuel reduction was obtained on the mixed city-motorway cycle. In this case, maximum speed is limited to 180km/h and the 0-100km/h acceleration is reduced to 11s (from the original 8.6s). The weight remains almost unaltered since the 204 HP engine is heavier than the 140 HP and this largely compensates the gearbox weight increase. The multiple speed solution seems to be very interesting also for public transports vehicles and for trucks. © 2015 Pushpa Publishing House, Allahabad, India.

Starting from a good automotive engine is always a good idea, also for brand new automotive design. In the case of automotive to aircraft conversions, the automotive engine is modified as little as possible. This approach has several advantages: reduced development time, good reliability and availability of cheap and worldwide spare parts. What it may appear a good idea is to tune up the original ECU (electronic control unit) by using one of the several softwares available on the market. However, this approach is not feasible even for ultra light aircrafts. This is due to the lack of control on the software of these ECUs. In fact, automotive software timing or ECU set-up is performed in the following way. The final ECU manufacturer (who holds the responsibility of the hardware and the software in the final car ECU) supplies to the car manufacturer a “development ECU” with a “development Software”. This system is tuned on the engine and on the car to fulfill the car manufacturer requirement. When the tuning is considered satisfactory, the “maps” (the data inputted by the manufactured) are given to the ECU manufacturer. This later translates the data into the software of a “production ECU”, that is given back to the car manufacturer for final validation prior to serial production of ECU and car. In this case, even the car manufacturer does not have a full control of what happens inside his ECU. This is logical since the full responsibility is given to the ECU part supplier. So the tuning of a serial production ECU is more than a true programming. Results are unpredictable to a certain extent that depends on the level of knowledge of the person who performed the tuning and of the software house that implemented the software. The software that truly runs on serial production ECU is a well kept secret of the ECU manufacturer, since it is the knowledge of ECU. The simpler is the software the less expensive will be the ECU and the larger the profits of the ECU supplier. Tricks are hidden inside the ECU to obtain these results; these tricks multiplied per millions of ECU give the supplier a competitive advantage. So, even the car manufacturer has a limited control on what happens inside the real-time software of the ECU, what emerges is the engine and the car behavior. Aircraft conversions require the replacement of ECU, wirings and sensors with appropriate units. This assembly with its own software constitutes the aircraft FADEC.

This paper describes a handheld application to help pilots when entering degraded visibility conditions. In this case, the loss of control is a typical emergency situation from which a pilot should be able to recover, but often he/she doesn’t do owing to problems of situation awareness. A new instrument, based on the use of accelerometers/GPS equipping modern handheld devices has been designed, virtually tested in flight simulators and finally tested in flight. Attention has been given to show essential information in a very simple and intuitive way, so that the instrument can be useful in case of pilot disorientation, panic or high stress levels. After a testing phase, the instrument showed useful to provide an indication about the attitude of the plane and to provide the pilot an indication of the stick and throttle movements needed to restore a safe levelled flight. The use of this application by pilots in emergency situation can enhance the survivability in Instrument Meteorological Conditions also without a specific training. This paper shows how the high computation capability and advanced visualization devices typical of smartphones can be useful to increase the flight safety by developing a new class of emergency not-certified instruments. A further testing phase of the instrument in critical conditions like gusty environment or deteriorated weather will be carried out as a future development of this work to better evaluate the limits of the instrument herein described. Copyright © 2016 Praise Worthy Prize - All rights reserved.

This paper presents a novel concept of container mobile housing system denominated ZETHa (Zero Energy Temporary Habitation). It is based on the LESP (Low Exergy Structured Panel) concept, in which the acclimatization is realized by water recirculation inside the external walls of the building and the ZEBRA concept (Zero Energy Consumption Building totally Renewable Addicted). A general plant and building design has been produced with the aim to minimize the presence of thermal bridges. The calculations of energy dispersion have been performed both in the wall and in the whole building. The energetic contribution of renewable energy plants has been evaluated to obtain a totally passive building. This evaluation will also consider energy needs by appliances.Copyright © 2012 by ASME

A new generation of aircraft piston engines is currently being introduced on the market. These new engines come directly from the huge experience achieved in the motorcycle and automotive racing and production. However direct use of automotive power unit is not advisable, since car engines work mainly in the first quarter of the power output, while sport motorcycles are used in a very "light" way, with the engines that span several times through the entire range of power outputs and rpm. The other problem is fuel. Aircraft spark ignition engine for ultralight and light aircrafts may continue to use automotive gasoline, while diesel engines for light up to cargo aircraft should use jet(A1) and jp4. However, the large experience obtained from racing/high-performance motorcycles, racing/high-performance cars and common rail engines cannot be ignored. Thousand of hours and billion of Euros have been spent for this development and the results are interesting. This paper tries to calculate the future aircraft engine performance from the many experimental data already available on a certain type of combustion chamber or better from a well defined and experimented cylinder unit. On the other side the "lean-thinking" approach to aircraft engine design may be not applicable. The lean thinking approach tends to prefer the time-to-market to the optimization of the engine unit. With engines that will probably stay on the market for 30 years this approach is not convenient. An important optimization during the design phase is possible with modern CAD tools. Mass and cost reduction may easily reach the 30%. On the other side the "brain storming approach" is not applicable to the heavily-constrained aircraft-engine design, where it is common that inapplicable solutions and ideas seem to be the best during the initial phase even to experts. Our research team developed three different families of engines: the first family uses the cylinder unit of a well proven motorcycle engine, which comes directly from racing and was sold in tenth of thousands in the world market. These spark ignition engines have 4 up to 16 cylinders (Figg. 1, 2), with power from 150 HP to 800 HP. This type of engines have very brilliant power to weight ratios with not superlative fuel consumptions. They are conceived for ultralight aircrafts and helicopters, tilt rotor, tilt shaft and tilt motor power lift V/STOL aircrafts. The second cylinder unit comes directly from the 2 valves FIAT 1900 jtd, that is one of the best two valves turbocharged common rail diesel available on the market. These units span from 4 up to 16 cylinders with power outputs from 175 HP (Fig. 3) up to 1000 HP. They run with jp4, jp8 or jet (A1) and can be bolted directly to the original engine mount of existing light aircraft like Cessna 172/182/337 or can be used in new light aircrafts. The third one is an originally conceived twin combustion chamber diesel family with output power from 600 HP to 4000 HP (hybrid engine) originally conceived for the Hercules C130J, ATR42 or ATR72 aircrafts (Figg. 4, 5). Our hybrid engine is composed by two separate engines: the VD007 diesel and a turboshaft. Each engine moves a separate contra rotating propeller. In ordinary flight the turboshaft works as a turbocharger. In this case the rear propeller is nearly idle. During take off or emergency the turboshaft combustion chamber is activated and additional power is available. In this case pitch is given to the rear propeller that outputs additional useful thrust. All these engines use only the thermo-fluid-dynamics and a few parts of the original cylinder unit, since aircraft application need extended modifications and, in many cases, complete redesign. However on all these engines a large amount of experimental, road and reliability data are available. Their direct application in the aircraft field is a plain mistake, since automotive and motorcycle are very different, but it is not the case to discard all this data that are available for free. For this reason innovative simulation methods were used to obtain engine performance envelope, with the possibility to choose the most convenient off-design solution on a certain aircraft, depending on the use and on the requirements. It is also possible to obtain reliability data for the aircraft FADEC (Full Authority Digital Engine Control) that controls all these new units. It is important to underline that airborne FADECs should be completely different from ground borne FADECs since in the aircraft application recovery strategies are to be chosen by the well trained pilot, while in the automotive field recovery is usually applied automatically in order to preserve engine integrity. A new method for the determination of the engine performance envelope is introduced as an example on the turbo/hybrid diesel unit for the C130J; this engine is called VD007. This approach has been successfully applied on the small diesel jtd family and also to the spark ignition family. © 2008 by the American Institute of Aeronautics and Astronautics, Inc.

The KAD (Knowledge Aided Design) tool is developed to predict the performance of an F1 car in different driving conditions and with different configurations. The regulations to put in trimming a car, also in the exasperated technology of the competitions, still demand a remarkable dose of luck and an elevated number of tests. It is then important to know a set of regulations close to the optimal trim before testing the car on the track. The difficult phase of this process is to evaluate the lap time. As a matter of fact driving style, track conditions and car behavior should be simulated. The optimisation of the fuzzy controller that simulates the pilot for an F1 racing car is difficult due to handling problems and velocity of response. For this purpose a specific Genetic Algorithm (GA) was conceived and tuned to work with a lumped mass model of an F1 racing car for the optimization of the fuzzy controller that simulates the pilot. A new mutation and a new crossover operator were defined to complement the standard crossover and mutation operators of the basic Holland’s GA. This was necessary in order to increase the overall performance of the fuzzy pilot. This approach was tested on an F1 car due to the huge amount of data available ( Donnarumma, 1998 , Moelenbein, 1989 ; Lee and Takagi, 1993 ).