Decreased resting and nursing in short-finned pilot whales when exposed to louder petrol engine noise of a hybrid whale-watch vessel

Vessel noise is a primary driver of behavioural disturbance in cetaceans, which are targeted during whale-watch activities. Despite the growing, global effort for implementing best-practice principles, to date, there are no regulations on whale-watch vessel noise levels. Here, we test the hypothesis that a whale-watch vessel with a low noise emission will not elicit short-term behavioural responses in toothed whales compared to a vessel with a louder engine. We measured behavioural responses (n = 36) of short-finned pilot whales (Globicephala macrorhynchus) to whale-watch vessel approaches (range 60 m, speed 1.5 kn). Treatment approaches with a quieter electric engine (136–140 dB) compared to the same vessel with a louder petrol engine (151–139 dB) (low-frequency–mid-frequency weighted source levels, re 1 µPa RMS @ 1 m) were examined. Focal whales were resting mother and calves in small group sizes. During petrol engine treatments, the mother’s mean resting time decreased by 29% compared to the control (GLM, p = 0.009). The mean proportion of time nursing for the calf was significantly influenced by petrol engine vessel passes, with a 81% decrease compared to the control (GLM, p = 0.01). There were no significant effects on behaviour from the quieter electric engine. Thus, to minimise disturbance on the activity budget of pilot whales, whale-watch vessels would ideally have source levels as low as possible, below 150 dB re 1 µPa RMS @ 1 m and perceived above ambient noise.

Architecture of Distributed Control System for Gearbox-Free More Electric Turbofan Engine

This article presents the development of the electric turbofan engine in distributed architecture with a design thrust in the range of 3 to 7.5 and from 7.5 to 30 kN for small and medium-sized unmanned aerial vehicles. The engine subsystems are considered as separate smart modules with a built-in control system, exchanging data via a digital channel with the central engine control and diagnostics unit. The key smart engine units are combined in the following subsystems: starter and turbine generators, oil pumps, actuator of guide vanes, fuel pumps, fuel metering unit, control and diagnostic unit. All pumps and guide vane actuator are electrically driven. Control and monitoring signals are transmitted via a digital bus. Functional and reliability analysis and the technical configuration design of each subsystem are presented. Based on analysis of the architecture of distributed control systems for a gearbox-free electric engine, different configurations of described subsystems are proposed.

Design Optimization of Electrodynamic Structure of Permanent Magnet Piston Mechanical Electric Engine

To meet the demand of multiple power requirements, and enhance power utilization, a new type of dual-element electricity unit is designed in this study, which is a permanent magnet piston mechanical electric engine. Based on the analysis method of traditional internal combustion engines and linear generators, the working principle of the engine and the magnetic field distribution in the electrodynamic structure are analyzed, the machine dynamics model and electrodynamics model of the engine are established, then the theoretical evaluation is additionally established using finite elements. Based on this, an optimization model is constructed with the electrodynamic shape dimension as the optimization variable, with the intention of growing the output power. The optimization of the engine electrodynamic shape is executed via the use of the finite aspect approach and the NLPQL optimization algorithm integrated. The results show that the optimized engine output electricity expanded to 8.40 w, which is 18.81% greater than before optimization. An experimental prototype is developed, and the output voltage of the prototype is measured to verify the precept and overall performance of the new structure.

Architecture of Distributed Control System for Gearbox-Free More Electric Turbofan Engine

The article presents development of the more electric turbofan engine in distributed architecture with a design thrust in the range from 3 to 7.5 and from 7.5 to 30 kN for small and medium-sized unmanned aerial vehicles. The engine subsystems are considered as separate smart modules with a built-in control system, exchanging data via a digital channel with the central engine control and diagnostics unit. The key smart engine units are combined in the following subsystems: starter and turbine generators, oil pumps, actuator of guide vanes, fuel pumps, fuel metering unit, control and diagnostic unit. All pumps and guide vane actuator are electrically driven. Control and monitoring signals are transmitted via a digital bus. Functional and reliability analysis, technical configuration design of each subsystem are presented. Based on analysis of the architecture of distributed control system for gearbox-free more electric engine, different configurations of described subsystems are proposed.

Subsystems of Electric Vehicle: Overview

Not long prior to entering the 20th Century, the most popular sort of transport at this point was the horse. Be that as it may, as individuals’ wages expanded and developments progressed, some were starting to explore different ways regarding more up-to-date types of transport. Presently, gas, steam, and electrical power were all available, with each following strength watching out. Steam development was grounded as of now and was generally seen and trusted by individuals all in all. It had, in light of everything, showing its worth driving assembling plants, mines, get ready, and conveys – it had all the earmarks of being only a trademark development to collect more unobtrusive kinds of transport using steam engines. There was an issue – steam motors were too slow to warm up and especially during winters it was particularly very tough to start them and once started the person had to continuously supply water for its cooling. They likewise had a restricted reach and should have been continually taken care of with water. Electric vehicles, or EVs for short, work using an electric engine rather than an interior ignition motor, similar to gas-fueled vehicles. Much of the time, EVs utilize an enormous footing battery pack to control the engine. This battery pack is charged by being connected to an exceptionally planned charging station or outlet at the clients’ homes. As EVs run on power, they have no fumes and don’t contain parts like the fuel siphon, fuel line, carburetor, and gas tank, which are required in gas-controlled vehicles. But the evidence of the positives has gotten amazingly clear, there are also a couple of hindrances that every individual needs to consider before they choose to make an electric vehicle their next tremendous undertaking. The reasons being: – Recharge Points, The Initial Investment is Steep, Short Driving Range and Short Driving Speed, Not Suitable for Cities, Facing Shortage of Power. To overcome the challenges more and more research and development work has been carried out and most of the above-stated challenges have been resolved. Higher battery density for longer range, alternate Li-ion batteries to increase the efficiency and to reduce the initial cost, and powerful chargers for fast charging is going under continuous development. Li-ion batteries undergo performance degradation and cycle aging, and it needs to be identified as soon as possible, i.e., using a Recommended Architecture to improve the performance of an EV. Apart from these, EV offers easy and efficient testing and verification model.

The Influence of Technological and Operational Factors on the Durability of the Shafts of Air-Cooler Unit Electric Motors

The paper presents the results of the study of fragments of the electric engine rotor shafts of the air-cooled units in order to establish the causes of its destruction. Chemical composition, type of the fracture, macro-and microstructure, as well as the mechanical properties of the metal are studied. Structural and technological factors contributed to the destruction are identified.

Design and Performance of a Compact Air-Breathing Jet Hybrid-Electric Engine Coupled With Solid Oxide Fuel Cells

A compact air-breathing jet hybrid-electric engine coupled with solid oxide fuel cells (SOFC) is proposed to develop the propulsion system with high power-weight ratios and specific thrust. The heat exchanger for preheating air is integrated with nozzles. Therefore, the exhaust in the nozzle expands during the heat exchange with compressed air. The nozzle inlet temperature is obviously improved. SOFCs can directly utilize the fuel of liquid natural gas after being heated. The performance parameters of the engine are acquired according to the built thermodynamic and mass models. The main conclusions are as follows. 1) The specific thrust of the engine is improved by 20.25% compared with that of the traditional jet engine. As pressure ratios rise, the specific thrust increases up to 1.7 kN/(kg·s−1). Meanwhile, the nozzle inlet temperature decreases. However, the temperature increases for the traditional combustion engine. 2) The power-weight ratio of the engine is superior to that of internal combustion engines and inferior to that of turbine engines when the power density of SOFC would be assumed to be that predicted for 2030. 3) The total pressure recovery coefficients of SOFCs, combustors, and preheaters have an obvious influence on the specific thrust of the engine, and the power-weight ratio of the engine is strongly affected by the power density of SOFCs.

Electric Power Transfer Concept for Enhanced Performance of the More Electric Engine

In future electrified aircraft, multi-spool more electric engines (MEEs) are expected to be equipped with electric generators connected to each shaft for power offtake and supplying onboard electrical loads. These can be interfaced to a common high-voltage DC bus architecture via power electronic converters. Such system architecture enables the establishment of an "electrical bridge" to circulate the desired amount of power between the engine shafts, and decouple their speeds. This paper introduces the possible benefits from the Electric Power Transfer (EPT) for engine performance and scrutinizes a novel EPT-Adopted Design (EPTAD) for future MEEs. For this purpose, a 0-dimensional engine model has been developed by using the inter-component-volume (ICV) method. By using the engine model, the CFM56-3 engine is redesigned to realize the EPTAD. Comparing the simulation results for the EPTAD and baseline CFM56-3 engines shows significant improvement for engine performance in terms of SFC and surge margin, mainly at cruise condition. Results show that almost 3.2% and 2.2% of fuel burn reduction is achieved for the short- and medium-haul flights respectively, with a 1150 kW EPT system. It is also shown that Variable Bleed Valves (VBVs) can be eliminated in the EPTAD engine with a 1150 kW EPT system.