scholarly journals PREMIUM YACHT PROPULSION FOR EXCLUSIVE PERFORMANCE

2019 ◽  
Author(s):  
A Witschel
Keyword(s):  
Fuel Consumption ◽  
Low Noise ◽  
Operating Costs ◽  
Shallow Waters ◽  
Propulsion Systems ◽  
Propulsive Efficiency ◽  
Course Stability ◽  
Wide Range ◽  
Overall Efficiency ◽  
Reduced Emissions

SCHOTTEL offers a wide range of main and auxiliary propulsion systems for yachts. This paper will present characteristics of different propulsion solutions: The 5-bladed controllable pitch propeller for highest propulsive efficiency for changing speed or load or the EcoPeller with best values in overall efficiency and course stability. It provides unprecedented performance and ensures that its owners benefit from low fuel consumption and thus reduced emissions and operating costs. Thanks to an installation flush with the hull, the pump jet is ideal for operation in extremely shallow waters. It can be used as manoeuvring aid, additional booster or take-home device. Low-vibration and low-noise rim thruster enables more comfort on board.

APEKS - a method of making decisions

2021 ◽  
Vol 12 (1) ◽  
pp. 45-50
Author(s):  
Jan Szybka ◽  
Sylwester Pabian
Keyword(s):  
Fuel Consumption ◽  
Evaluation Criteria ◽  
Operating Costs ◽  
Passenger Car ◽  
Utility Values ◽  
Decision Method ◽  
Individual Comparison ◽  
Wide Range ◽  
Aesthetic Values ◽  
Selection Of

The APEKS method was developed in the 1970s. It has a wide range of applications for making a decision. The article describes the APEKS method, which is a multi-criteria method and consists of 10 steps. The application of this method was presented in the example of car selection. The problem of choosing a passenger car was analyzed taking into account 6 evaluation criteria: fuel consumption, power, price, annual operating costs, aesthetic values, and utility values. Following the APEKS method, the analysis was completed with the selection of the best variant, using the forced decision method, consisting of an individual comparison of all criteria with one another. The APEKS variant is used for this, which has all the best features of the variants to choose from. This indicates that APEKS is an idealized and fictional variant.

Evolution of the Turboprop for High Speed Air Transportation

1978 ◽  
Author(s):  
G. E. Holbrook ◽  
G. Rosen
Keyword(s):  
Fuel Consumption ◽  
Noise Level ◽  
High Speed ◽  
Cost Effective ◽  
Air Transportation ◽  
Low Noise ◽  
The Other ◽  
Propulsion Systems ◽  
Maintenance Costs ◽  
Passenger Comfort

Since they first entered military and commercial service during the 1950’s, U.S.-manufactured turbopropeller engines have proved to be reliable, fuel-efficient propulsion systems for aircraft. Despite their somewhat greater mechanical complexity when comprared with turbofans, the repair and maintenance costs of the turboprops compare very favorably with those of the other types, and their substantially reduced fuel consumption and low noise level merit serious consideration for aircraft in an energy and environmentally critical future. Advancements in propeller/fan aerodynamic and structural technologies now permit flight speeds up to Mach 0.85, making turly cost-effective aircraft possible, while retaining present standards of passenger comfort and powerplant reliability.

Diesel Traction

1933 ◽  
Vol 125 (1) ◽  
pp. 537-613 ◽  
Author(s):  
G. V. Lomonossoff
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Experimental Work ◽  
Point Of View ◽  
Operating Costs ◽  
Direct Drive ◽  
Diesel Locomotive ◽  
Maintenance Costs ◽  
Overall Efficiency ◽  
Railway Operation

The author points out the difficulty in designing steam locomotives of high overall efficiency, no matter to what type they may belong, and shows that the efficiency of Diesel locomotives is considerably higher, while they also possess certain other advantages, particularly in bringing about a reduction in permanent way maintenance costs. Early Diesel locomotives are described and an account is given of the collaboration between the German and Russian railways, to investigate various types of transmission, and of the transportable locomotive laboratory which was built for carrying out the necessary tests. The economic aspect of railway operation is carefully analysed, and the results of extended trials in Russia of steam, Diesel-electric, and Diesel geared locomotives are given and compared with the latest available figures for operating costs in this country, and with figures for sparsely populated regions in Asia. The author, while not advocating wholesale adoption of Diesel locomotives everywhere, arrives at the conclusion that they have a definite sphere of usefulness, particularly in regions where water is scarce or of bad quality. He also emphasizes the necessity for standardized types of Diesel locomotives, and suggests that owing to the inherent drawbacks in the transmissions both of the Diesel-electric and Diesel geared types, there may be a future for the Diesel locomotive with direct drive with an enlarged engine, provided that, by research and experimental work, the difficulties previously encountered with direct drive can be removed. The author also notes that from the point of view of fuel consumption and simplicity the speed of the Diesel engine and the number of cylinders should not exceed certain limits.

scholarly journals Measurements of Basic Performances for Waterjet Propulsion Systems in Water Tunnel

1995 ◽  
Vol 2 (1) ◽  
pp. 43-50 ◽  
Author(s):  
Nobuyuki Fujisawa
Keyword(s):  
Field Experiment ◽  
Reasonable Agreement ◽  
Model Systems ◽  
Experimental Techniques ◽  
Water Tunnel ◽  
Nozzle Outlet ◽  
Propulsion Systems ◽  
Propulsive Efficiency ◽  
Optimization Study ◽  
Wide Range

Experimental techniques are described in detail for evaluating the system and the unit performances of waterjet propulsion systems in a water tunnel. The measured performances of pump and propulsion of the model systems are in reasonable agreement with the field experiment with prototype craft. Measurements are also made for the losses in the intake and the nozzle. The optimization study of the water jet systems is conducted by simulating the change of the nozzle outlet diameter with the variable nozzle arrangement. It is suggested that the nozzle outlet diameter should be decreased as the craft velocity increases to obtain an optimum propulsive efficiency in a wide range of craft velocity.

scholarly journals Evaluation and Comparison of Hybrid Wing VTOL UAV with Four Different Electric Propulsion Systems

Aerospace ◽  
2021 ◽  
Vol 8 (9) ◽  
pp. 256
Author(s):  
Jianan Zong ◽  
Bingjie Zhu ◽  
Zhongxi Hou ◽  
Xixiang Yang ◽  
Jiaqi Zhai
Keyword(s):  
Fuel Consumption ◽  
Electric Propulsion ◽  
Low Noise ◽  
Urban Traffic ◽  
Aviation Industry ◽  
Propulsion Systems ◽  
Performance Requirements ◽  
Vtol Uav ◽  
Battery Energy ◽  
Selection Of

Electric propulsion technology has attracted much attention in the aviation industry at present. It has the advantages of environmental protection, safety, low noise, and high design freedom. An important research branch of electric propulsion aircraft is electric vertical takeoff and landing (VTOL) aircraft, which is expected to play an important role in urban traffic in the future. Limited by battery energy density, all electric unmanned aerial vehicles (UAVs) are unable to meet the longer voyage. Series/parallel hybrid-electric propulsion and turboelectric propulsion are considered to be applied to VTOL UAVs to improve performances. In this paper, the potential of these four configurations of electric propulsion systems for small VTOL UAVs are evaluated and compared. The main purpose is to analyze the maximum takeoff mass and fuel consumption of VTOL UAVs with different propulsion systems that meet the same performance requirements and designed mission profiles. The differences and advantages of the four types propulsion VTOL UAV in the maximum takeoff mass and fuel consumption are obtained, which provides a basis for the design and configuration selection of VTOL UAV propulsion system.

scholarly journals Feasibility of a Helium Closed-Cycle Gas Turbine for UAV Propulsion

2020 ◽  
Vol 11 (1) ◽  
pp. 28
Author(s):  
Emmanuel O. Osigwe ◽  
Arnold Gad-Briggs ◽  
Theoklis Nikolaidis
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Pressure Ratio ◽  
Low Noise ◽  
Closed Cycle ◽  
Propulsion Systems ◽  
Component Design ◽  
Readiness Level ◽  
Aerial Vehicle ◽  
Turbine Design

When selecting a design for an unmanned aerial vehicle, the choice of the propulsion system is vital in terms of mission requirements, sustainability, usability, noise, controllability, reliability and technology readiness level (TRL). This study analyses the various propulsion systems used in unmanned aerial vehicles (UAVs), paying particular focus on the closed-cycle propulsion systems. The study also investigates the feasibility of using helium closed-cycle gas turbines for UAV propulsion, highlighting the merits and demerits of helium closed-cycle gas turbines. Some of the advantages mentioned include high payload, low noise and high altitude mission ability; while the major drawbacks include a heat sink, nuclear hazard radiation and the shield weight. A preliminary assessment of the cycle showed that a pressure ratio of 4, turbine entry temperature (TET) of 800 °C and mass flow of 50 kg/s could be used to achieve a lightweight helium closed-cycle gas turbine design for UAV mission considering component design constraints.

A Variable-Geometry Power Turbine for Marine Gas Turbines

1989 ◽  
Author(s):  
Karl W. Karstensen ◽  
Jesse O. Wiggins
Keyword(s):  
Fuel Consumption ◽  
Gas Turbines ◽  
Part Load ◽  
Surface Ship ◽  
Marine Propulsion ◽  
Medium Speed ◽  
Power Turbine ◽  
Wide Range ◽  
Electrical Generator ◽  
Variable Power

Gas turbines have been accepted in naval surface ship applications, and considerable effort has been made to improve their fuel consumption, particularly at part-load operation. This is an important parameter for shipboard engines because both propulsion and electrical-generator engines spend most of their lives operating at off-design power. An effective way to improve part-load efficiency of recuperated gas turbines is by using a variable power turbine nozzle. This paper discusses the successful use of variable power turbine nozzles in several applications in a family of engines developed for vehicular, industrial, and marine use. These engines incorporate a variable power turbine nozzle and primary surface recuperator to yield specific fuel consumption that rivals that of medium speed diesels. The paper concentrates on the experience with the variable nozzle, tracing its derivation from an existing fixed vane nozzle and its use across a wide range of engine sizes and applications. Emphasis is placed on its potential in marine propulsion and auxiliary gas turbines.

LOW-NOISE SILICON-ON-INSULATOR HALL DEVICES

2004 ◽  
Vol 04 (02) ◽  
pp. L345-L354 ◽  
Author(s):  
Y. HADDAB ◽  
V. MOSSER ◽  
M. LYSOWEC ◽  
J. SUSKI ◽  
L. DEMEUS ◽  
...  
Keyword(s):  
Noise Level ◽  
Low Voltage ◽  
Silicon Layer ◽  
Electrical Current ◽  
Low Noise ◽  
Silicon On Insulator ◽  
Technological Parameters ◽  
Wide Range ◽  
Hall Sensors ◽  
Soi Technology

Hall sensors are used in a very wide range of applications. A very demanding one is electrical current measurement for metering purposes. In addition to high precision and stability, a sufficiently low noise level is required. Cost reduction through sensor integration with low-voltage/low-power electronics is also desirable. The purpose of this work is to investigate the possible use of SOI (Silicon On Insulator) technology for this integration. We have fabricated SOI Hall devices exploring the useful range of silicon layer thickness and doping level. We show that noise is influenced by the presence of LOCOS and p-n depletion zones near the edges of the active zones of the devices. A proper choice of SOI technological parameters and process flow leads to up to 18 dB reduction in Hall sensor noise level. This result can be extended to many categories of devices fabricated using SOI technology.

A Discussion of Pod Drives and Their Application In the Pleasure Boat Market

2009 ◽  
Author(s):  
Christopher Swanhart
Keyword(s):  
North America ◽  
General Information ◽  
Low Noise ◽  
Noise Levels ◽  
Propulsion Systems ◽  
Fully Integrated ◽  
Operator Interface ◽  
Performance System ◽  
Hull Forms

Since being introduced to North America at the Miami Boat Show in 2005, Volvo Penta Inboard Performance System, or IPS has established itself as a leading propulsion choice among pleasure boat owners and builders. Other suppliers are following suit including the Cummins Mercruiser Zeus system. Pod propulsion offers benefits like increased efficiency, better performance, nimble handling, and low noise levels while allowing more people to successfully operate their vessel due to a friendly operator interface. Features of these commercial pod systems that also benefit builders include ease of installation and the integral underwater exhaust which helps to meet CE requirements, for both exhaust and noise levels. Both IPS and Zeus are fully integrated pod propulsion systems. Existing vessels can be retro-fitted with these systems while many new vessels are being designed specifically for IPS or Zeus. Donald L. Blount and Associates provides consulting in regards to IPS integration with existing and new designs and has also been involved with designs employing the Zeus system. The first portion of this paper discusses pod drives, particularly IPS itself. (Because the author has substantially more experience and background with IPS, much of the information herein is IPS specific). General information on IPS and Zeus is offered as well as some operational specifics. The paper then focuses on the application of pod drives in existing and new vessel designs. The discussion includes how hull forms can be evaluated for use with pod drives. A look at the integration of pod systems into various types of pleasure boats (cruiser, day boat, fishing yacht, etc) is also covered including the challenges which exist for each specific vessel type.

scholarly journals Real-World Measurement of Hybrid Buses’ Fuel Consumption and Pollutant Emissions in a Metropolitan Urban Road Network

Energies ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2569 ◽  
Author(s):  
Christos Keramydas ◽  
Georgios Papadopoulos ◽  
Leonidas Ntziachristos ◽  
Ting-Shek Lo ◽  
Kwok-Lam Ng ◽  
...  
Keyword(s):  
Fuel Consumption ◽  
Road Network ◽  
Pollutant Emissions ◽  
Emission Measurement ◽  
Body Type ◽  
Urban Road Network ◽  
Urban Road ◽  
Wide Range ◽  
The Mean ◽  
Consumption Benefits

This study investigates pollutant emissions and fuel consumption of six Euro VI hybrid-diesel public transport buses operating on different scheduled routes in a metropolitan urban road network. Portable emission measurement systems (PEMS) are used in measurements and results are compared to those obtained from a paired number of Euro V conventional buses of the same body type used as control over the same routes. The selected routes vary from urban to highway driving and the experimentation was conducted over the first half of 2015. The available emissions data correspond to a wide range of driving, operating, and ambient conditions. Fuel consumption, distance- and energy-based emission levels are derived and presented in a comparative manner. The effect of different factors, including speed, ambient temperature, and road grade on fuel consumption and emissions performance is investigated. Mean fuel consumption of hybrid buses was found 6.1% lower than conventional ones, from 20% lower up to 16% higher, over six routes tested in total. The mean route difference between the two technologies was not statistically significant. Air conditioning decreased consumption benefits of the hybrid buses. Decrease of the mean route speed from 15 km h−1 tο 8 km h−1 increased the hybrid buses consumption by 63%. Nitrogen oxides (NOx) emissions of the Euro VI hybrid buses were 93 ± 5% lower than conventional Euro V ones. Nitrous oxide (N2O) emissions from hybrid Euro VI buses made up 5.9% of total greenhouse gas emissions and largely offset carbon dioxide (CO2) benefits. The results suggest that hybrid urban buses need to be assessed under realistic operation and environmental conditions to assess their true environmental and fuel consumption benefits.

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