scholarly journals Bearing Power Losses with Water-Containing Gear Fluids

Lubricants ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 5 ◽  
Author(s):  
Mustafa Yilmaz ◽  
Thomas Lohner ◽  
Klaus Michaelis ◽  
Karsten Stahl
Keyword(s):  
Power Loss ◽  
Stribeck Curve ◽  
Detailed Knowledge ◽  
Power Losses ◽  
Test Rig ◽  
Load Bearing ◽  
Gear Efficiency ◽  
Efficiency Test ◽  
Typical Calculation ◽  
Calculation Procedures

Lubricants have a large influence on gearbox power losses. Recent investigations at a gear efficiency test rig have shown the high potential of water-containing gear fluids in drastically reducing load-dependent gear losses and temperatures. In this study, the bearing power losses with water-containing gear fluids were evaluated at a specific bearing power loss test rig explicitly and compared with mineral and polyalphaolefine oils. For all investigated lubricants, a Stribeck curve behavior of the load-dependent losses is observed. The water-containing gear fluids demonstrate lower no-load bearing losses and higher load-dependent bearing losses at higher rotational speeds. The comparison of measured bearing losses with typical calculation procedures showe partially large differences. The results underline the importance of having detailed knowledge of bearing losses when evaluating gear losses in gearboxes.

scholarly journals Calculating component temperatures in gearboxes for transient operation conditions

2021 ◽  
Author(s):  
Constantin Paschold ◽  
Martin Sedlmair ◽  
Thomas Lohner ◽  
Karsten Stahl
Keyword(s):  
Load Capacity ◽  
Transient Operation ◽  
System Of Differential Equations ◽  
Test Rig ◽  
Operation Conditions ◽  
Network Method ◽  
Gear Efficiency ◽  
Efficiency Test ◽  
Thermal Network Method ◽  
Specific Heat Capacities

AbstractThe knowledge of component temperatures during transient operation conditions is essential for an optimal design of a gearbox. This is because critical peak temperatures limit the transferable power as well as the load capacity. Moreover, understanding the thermal behavior of the gearbox is key to improving its efficiency. Therefore, the Thermal Network Method (TNM) of the calculation program WTplus was extended to calculate component temperatures in gearboxes for transient operation conditions. Specifically, the TNM considers the component masses and specific heat capacities of each node modelling the gearbox structure. This enables the algorithm to compute a corresponding system of differential equations and thus determine the temperature change over time. Therefore, WTplus can be used to identify critical gearbox component temperatures during load cycles. The applied method was validated with measurements collected at the FZG gear efficiency test rig.

Investigation of the power losses of the hybrid transmission DE-REX based on modeling and measurement

2019 ◽  
Vol 233 (14) ◽  
pp. 3646-3657
Author(s):  
Ye Shen ◽  
Andreas Viehmann ◽  
Stephan Rinderknecht
Keyword(s):  
Experimental Data ◽  
Electric Vehicles ◽  
Power Loss ◽  
The Novel ◽  
Power Losses ◽  
Test Rig ◽  
Hybrid Powertrain ◽  
Range Extender ◽  
Hybrid Powertrains ◽  
Hybrid Transmission

Electric and hybrid powertrains are developed to reduce the energy and fuel consumption of vehicles. Recently, multi-speed transmission systems were discussed for further reduction of the energy consumption of electric vehicles. Therefore, analyzing the power losses of such transmissions is of interest. In this paper, the novel powertrain concept DE-REX (Two-Drive-Transmission with Range-Extender) and the experimental investigation of its overall power losses is first introduced. A method is then developed to model and analyze the power losses of this hybrid transmission based on experimental data. After the validation of the method, the overall power loss model is eventually applied to estimate the power losses of the transmission at other driving modes, which were not measured on the test rig. The method is used to understand the characteristics of power losses inside the transmission in a hybrid powertrain and to optimize powertrain power losses in future.

A mixed finite element and analytical method to predict load, mechanical power loss and improved efficiency in non-standard spur gear drives

2017 ◽  
Vol 231 (11) ◽  
pp. 1408-1424 ◽  
Author(s):  
R Prabhu Sekar ◽  
V Edwin Geo ◽  
Leenus Jesu Martin
Keyword(s):  
Power Loss ◽  
Mixed Finite Element ◽  
Mechanical Efficiency ◽  
Spur Gear ◽  
Gear Ratio ◽  
Accurate Estimation ◽  
Power Losses ◽  
Contributing Factors ◽  
Comparative Performance ◽  
Gear Efficiency

A reasonably accurate estimation of gear power loss is desirable to maximize gear performance. The load share by teeth pair, contact stress, sliding speed, elastohydrodynamic film thickness and coefficient of friction are some of the most important contributing factors which determine frictional power losses in gears. This paper presents an improvement concept to minimize the load-related power losses (sliding and rolling power losses), which will lead to an enhancement in gear efficiency by selection of non-standard gears. The tooth thickness at the pitch circle of the pinion and gear is different in non-standard gears (kpπm > 0.5 πm and kgπm < 0.5 πm), whereas it is equal in standard gears (kpπm = kgπm = 0.5 πm). In this work, the load share-based frictional power loss and the respective mechanical efficiency have been determined for comparative performance of standard and non-standard gears. Finally, the influence of various gear and drive parameters such as gear ratio, pressure angle pinion teeth number and addendum height factor on gear efficiency has also been investigated and the results of the parametric study are discussed.

scholarly journals The Power Losses in Cable Lines Supplying Nonlinear Loads

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1374
Author(s):  
Bartosz Rozegnał ◽  
Paweł Albrechtowicz ◽  
Dominik Mamcarz ◽  
Monika Rerak ◽  
Maciej Skaza
Keyword(s):  
Bessel Function ◽  
Cross Section ◽  
Power Loss ◽  
Sine Wave ◽  
Active Power ◽  
New Method ◽  
Power Losses ◽  
Nonlinear Loads ◽  
Current Harmonics ◽  
Cable Lines

This paper presents the skin effect impact on the active power losses in the sheathless single-core cables/wires supplying nonlinear loads. There are significant conductor losses when the current has a distorted waveform (e.g., the current supplying diode rectifiers). The authors present a new method for active power loss calculation. The obtained results have been compared to the IEC-60287-1-1:2006 + A1:2014 standard method and the method based on the Bessel function. For all methods, the active power loss results were convergent for small-cable cross-section areas. The proposed method gives smaller power loss values for these cable sizes than the IEC and Bessel function methods. For cable cross-section areas greater than 185 mm2, the obtained results were better than those for the other methods. There were also analyses of extra power losses for distorted currents compared to an ideal 50 Hz sine wave for all methods. The new method is based on the current penetration depth factor calculated for every considered current harmonics, which allows us to calculate the precise equivalent resistance for any cable size. This research is part of our work on a cable thermal analysis method that has been developed.

scholarly journals An Improved Particle Swarm Optimization Algorithm Using Eagle Strategy for Power Loss Minimization

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Hamza Yapıcı ◽  
Nurettin Çetinkaya
Keyword(s):  
Genetic Algorithm ◽  
Particle Swarm Optimization ◽  
Power System ◽  
Power Loss ◽  
Particle Swarm Optimization Algorithm ◽  
Reactive Power ◽  
Particle Swarm ◽  
Power Losses ◽  
Swarm Optimization ◽  
Eagle Strategy

The power loss in electrical power systems is an important issue. Many techniques are used to reduce active power losses in a power system where the controlling of reactive power is one of the methods for decreasing the losses in any power system. In this paper, an improved particle swarm optimization algorithm using eagle strategy (ESPSO) is proposed for solving reactive power optimization problem to minimize the power losses. All simulations and numerical analysis have been performed on IEEE 30-bus power system, IEEE 118-bus power system, and a real power distribution subsystem. Moreover, the proposed method is tested on some benchmark functions. Results obtained in this study are compared with commonly used algorithms: particle swarm optimization (PSO) algorithm, genetic algorithm (GA), artificial bee colony (ABC) algorithm, firefly algorithm (FA), differential evolution (DE), and hybrid genetic algorithm with particle swarm optimization (hGAPSO). Results obtained in all simulations and analysis show that the proposed method is superior and more effective compared to the other methods.

An Experimental Methodology to Determine Components of Power Losses of a Gearbox

2021 ◽  
Vol 143 (11) ◽  
Author(s):  
A. Dindar ◽  
K. Chaudhury ◽  
I. Hong ◽  
A. Kahraman ◽  
C. Wink
Keyword(s):  
Power Loss ◽  
Spur Gear ◽  
Rolling Element Bearing ◽  
Experimental Methodology ◽  
Total Power ◽  
Gear Pair ◽  
Rolling Element Bearings ◽  
Power Losses ◽  
Rolling Element ◽  
The One

Abstract In this study, an experimental methodology is presented to separate various components of the power loss of a gearbox. The methodology relies on two separate measurements. One is designed to measure total power loss of a gearbox housing a single spur gear pair under both loaded and unloaded conditions such that load-independent (spin) and load-dependent (mechanical) components can be separated. With the assumption that gear pair and rolling element bearings constitute the bulk of the gearbox power loss, a second measurement system designed to quantify rolling element bearing losses is proposed. With this setup, spin and mechanical power losses of rolling element bearings used in the gearbox experiments are measured. Combining the sets of gearbox and bearing data, power loss components attributable to the gear pair and rolling element bearings are quantified as a function of speed and torque. The results indicate that all gear and bearing related components are significant and a methodology such as the one proposed in this study is warranted.

scholarly journals OPTIMASI PENEMPATAN KAPASITOR BANK UNTUK PERBAIKAN RUGI DAYA PADA PENYULANG SABA MENGGUNAKAN ALGORITMA GENETIKA

2019 ◽  
Vol 6 (2) ◽  
pp. 7
Author(s):  
I. K. A. Wijaya ◽  
R. S. Hartati ◽  
I W. Sukerayasa
Keyword(s):  
Genetic Algorithms ◽  
Power Loss ◽  
Voltage Drop ◽  
Electrical Energy ◽  
Total Power ◽  
Network Reconfiguration ◽  
Power Losses ◽  
Combined Method ◽  
Capacitor Banks ◽  
Distribution Transformers

Saba feeder is a feeder who supplies 78 distribution transformers with feeder length 38,959 kms, through this Saba feeder electrical energy is channeled radially to each distribution substation. In 2017 the voltage shrinkage at Saba feeder was 9.88% (18,024 kV) while the total power loss was 445.5 kW. In this study an attempt was made to overcome the voltage losses and power losses using the method of optimizing bank capacitors with genetic algorithms and network reconfiguration. The best solution obtained from this study will be selected for repair of voltage losses and power losses in Saba feeders. The results showed that by optimizing bank capacitors using genetic algorithms, the placement of capacitor banks was placed on bus 23 (the channel leading to the BB0024 transformer) and successfully reduced the power loss to 331.7 kW. The network reconfiguration succeeded in fixing the voltage on the Saba feeder with a voltage drop of 4.75% and a total power loss of 182.7 kW. With the combined method, reconfiguration and optimization of bank capacitors with genetic algorithms were obtained on bus 27 (channel to transformer BB0047) and managed to reduce power losses to 143 kW.

Reducing friction power losses of flywheel energy storage systems using PTFE composites: A technical note

2019 ◽  
Vol 233 (10) ◽  
pp. 1616-1621
Author(s):  
Shuyun Jiang ◽  
Yujiang Qiu
Keyword(s):  
Energy Storage ◽  
Power Loss ◽  
Magnetic Bearing ◽  
Technical Note ◽  
Flywheel Energy Storage ◽  
Power Losses ◽  
Spiral Groove ◽  
Friction Power ◽  
Ptfe Composites ◽  
Spiral Groove Bearing

This technical note aims to reduce friction power loss of flywheel energy storage system (FESS) supported by hydrodynamic spiral groove bearing and permanent magnetic bearing (PMB). An approach is proposed to fabricate the spiral groove bearing using polytetrafluoroethylene (PTFE) composite. A test rig is developed to test tribological properties of the spiral groove PTFE bearings. Also, two PTFE composites (C-PTFE: 80 vol.% PTFE filled with 20 vol.% graphite; C-Cu-PTFE 50 vol.% PTFE filled with 20 vol.% graphite and 30 vol.% copper powder) are tested. Results show that the friction power losses of the C-PTFE and C-Cu-PTFE bearings are lower than that of the traditional albronze (CuAl) bearing in the whole speed range. In addition, the spiral groove PTFE bearings show an excellent friction-reducing property under boundary or mixed lubrication condition. Finally, a case study is given to show the spiral groove PTFE bearing is capable of reducing the friction power loss of the FESS.

Thermal Analysis and Test for a High Speed PM Machine for Fan Application

2011 ◽  
Vol 383-390 ◽  
pp. 4727-4734 ◽  
Author(s):  
Ji Qiang Wang ◽  
Feng Xiang Wang
Keyword(s):  
Thermal Analysis ◽  
Temperature Rise ◽  
Power Loss ◽  
High Speed ◽  
Heat Dissipation ◽  
Machine Design ◽  
Test Results ◽  
Power Losses ◽  
Running Speed ◽  
High Speed Machine

For a give air flux, the higher speed the fanner is running, the smaller the fanner’s size is. It is also well known that for a given power, the higher the machine’s running speed, the smaller the machine’s size has. If the fanner is geared to a high speed machine directly, the fan set’s volume will be sharply decreased. However, the heat dissipation of the high speed machine becomes a serious problem also due to the small size and high power loss density. Therefore, how to estimate accurately the power losses and temperature rise is a key issue for the high speed machine design. In this paper, the power losses and temperature of high speed PM machine for a fanner application are thoroughly investigated. And the test results of a prototype fan set partly shown the validity of the calculation method.

Reducing Gear Windage Losses From High Speed Gears

2000 ◽  
Author(s):  
Don D. Winfree
Keyword(s):  
Power Loss ◽  
High Speed ◽  
Total Power ◽  
Fort Worth ◽  
Trial And Error ◽  
Test Rig ◽  
Cost Overruns ◽  
Basic Set ◽  
Drive Trains ◽  
Reducing Gear

Abstract Windage losses in gearboxes account for a large portion of the total power loss in high-speed drive trains. Very little actual data has been collected specifically quantifying these losses. Traditional techniques to measure the effects of baffles in high speed gearing applications have been done by trial and error on very complex systems. This trial and error technique is used throughout the gearing industry to solve problems without isolating each individual gear windage effect. These solutions are usually sub-optimum. They cause time-consuming delays and cost overruns in many programs. This paper describes a gear baffle test rig that was built to quantify and minimize the gear windage losses in high-speed drive trains. These tests were conducted at the Lockheed Martin Aeronautics Company, Fort Worth Texas Facility. The intent of the gearbox baffle test rig was to isolate and measure the windage effects on a single high-speed bevel gear with various baffle configurations. Results of these tests were used to define a basic set of ground rules for designing baffles. Finally the set of ground rules was used to design an optimum baffle configuration.

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