Experimental Study of Water Flow in Full-Size Test Rig for Water-Cooled Turbo-Generator Rotor

1966 ◽  
Vol 181 (1) ◽  
pp. 53-73 ◽  
Author(s):  
I. K. Csillag
Keyword(s):  
Operating Conditions ◽  
Experimental Investigations ◽  
Air Cooling ◽  
Test Rig ◽  
Full Size ◽  
Generator Rotor ◽  
Turbo Generator ◽  
Hydrogen Cooling ◽  
Major Factors ◽  
Design And Manufacture

The demand for electric power has doubled in the last decade. The most economical way to meet this demand is by building large-output generating units. The study of the major factors which determine the output of such generators shows that the only effective way to increase the output is by improving the cooling of their windings. For that reason design has progressed from air-cooling to indirect hydrogen-cooling, then to direct hydrogen-cooling. Now the trend is towards direct water-cooling where the water is in direct contact with the copper windings. The introduction of water into the stator winding was established in 1956 (1)† and was in fact directly responsible for the present increase in unit rating. The introduction of water to a rotating winding presents difficult problems in both design and manufacture. The test rig dealt with in this paper was built to study some of these problems and to carry out experimental investigations on a full size model of the special hydraulic features for a water-cooled turbo-generator rotor. The investigations were concentrated around the following five different problems which are dealt with in detail: (1) increase in pressure drop due to rotation; (2) free-rotating seal (inlet seal) (2); (3) vacuum-breaking device (water outlet) (3); (4) loss-distribution in the rotor; (5) measurement of the rotor vibrations in various operating conditions.

scholarly journals Design and Testing of a 10KW Steam Turbine for Steam Turbochargers

1985 ◽  
Author(s):  
M. Rautenberg ◽  
M. Malobabic ◽  
A. Mobarak ◽  
M. Abdel Kader
Keyword(s):  
Waste Heat ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Exhaust Gas ◽  
Test Rig ◽  
Pelton Turbine ◽  
Partial Admission ◽  
Turbine Design ◽  
Design And Testing

A Clausius-Rankine-cycle has been proposed to recover waste heat from a piston engine. This waste heat is then used to supercharge the cylinders by means of a steam turbocharger. The advantage of using this steam turbocharger system is to avoid the losses due to the engine back pressure which accompany the use of the conventional exhaust gas turbocharger. The mass flow rate of turbines for steam turbochargers in the range from 1 to 10 kW is about 0.03 to 0.08 kg/s. This implies a special turbine design, characterised by partial admission and supersonic flow, which unfortunately leads to low turbine efficiencies. A small Pelton turbine for steam has been designed and produced. The turbine is connected to the radial compressor of a conventional exhaust gas turbocharger which works, in this case, as a brake to dissipate the generated turbine power. A special test rig has been built to carry out the experimental investigations on the proposed Pelton turbine. The test rig is supplied with superheated steam from the University’s power plant. Two different rotors for this Pelton turbine have been tested under the same operating conditions (rotor 2 see Fig. 1). Some experimental test results of a special Pelton turbine are presented and discussed in this report.

Evaluation of a New Design Concept for a Ceramic Flame Tube Under Engine Conditions

1996 ◽  
Author(s):  
S. Münz ◽  
A. Schulz ◽  
S. Wittig
Keyword(s):  
Gas Turbine ◽  
Thermal Load ◽  
Operating Conditions ◽  
Design Concept ◽  
Experimental Investigations ◽  
Test Bed ◽  
Test Rig ◽  
Ceramic Structure ◽  
Flame Tube ◽  
Design Concepts

At the Institut für Thermische Strömungsmaschinen in Karlsruhe new design concepts for thermally high-loaded ceramic gas turbine components were developed. The present concept is based on a load-oriented segmentation in combination with a flexible suspension and thermal insulation of the ceramic structure. The concept was applied to a flame tube for a small gas turbine. In order to ensure real operating conditions, a Klöckner Humboldt Deutz T216 type gas turbine was used as test bed for the ceramic combustor. The paper gives a description of the combustor and the test rig. Furthermore, experimental results of the engine tests with special emphasis on the liner wall temperature distribution for various steady and transient operating conditions are presented. A major result of the tests is that the design concept proved to be reliable under real engine conditions. After more than 100 hours no failure of the ceramic parts occured. In order to determine the thermal load of the ceramic flame tube under real conditions, the experimental investigations are supported by numerical calculations.

scholarly journals Experimental investigations and analysis on churning losses of splash lubricated spiral bevel gears

2017 ◽  
Vol 18 (4) ◽  
pp. 412 ◽  
Author(s):  
S. Laruelle ◽  
C. Fossier ◽  
C. Changenet ◽  
F. Ville ◽  
S. Koechlin
Keyword(s):  
Experimental Tests ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Spiral Bevel Gear ◽  
Power Losses ◽  
Test Rig ◽  
Specific Test ◽  
Spiral Bevel Gears ◽  
Bevel Gears ◽  
Spiral Bevel

Churning losses are a complex phenomenon which generates significant power losses when considering splash lubrication of gear units. However, only few works deal with bevel gears dipped lubrication losses. The objective of this study is to provide a wide variety of experimental tests on churning losses, especially getting interested in geometry of spiral bevel gears influence. A specific test rig was used in order to study a single spiral bevel gear partially immersed in an oil bath. Experiments have been conducted for several operating conditions in terms of speeds, lubricants, temperatures and gear geometries to study their impact on splash lubrication power losses. These experimental results are compared with the predictions from various literature sources. As the results did not agree well with the predictions for all operating conditions, an extended equation derived from previous works is introduced to estimate churning losses of bevel gears.

DLC-coated spur gears – part I: friction reduction

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Andreas Schwarz ◽  
Martin Ebner ◽  
Thomas Lohner ◽  
Karsten Stahl ◽  
Kirsten Bobzin ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Operating Conditions ◽  
Friction Reduction ◽  
Experimental Investigations ◽  
Bulk Temperature ◽  
Test Rig ◽  
Dlc Coatings ◽  
Content Type ◽  
Temperature Reduction ◽  
Insulation Effect

Purpose This paper aims to address the influence of diamond-like carbon (DLC) coatings on the frictional power loss of spur gears. It shows potentials for friction and bulk temperature reduction in industrial use. From a scientific point of view, the thermal insulation effect on fluid friction is addressed, which lowers viscosity in the gear contact due to increasing contact temperature. Design/methodology/approach Thermal insulation effect is analyzed in detail by means of the heat balance and micro thermal network of thermal elastohydrodynamic lubrication contacts. Preliminary results at a twin-disk test rig are summarized to categorize friction and bulk temperature reduction by DLC coatings. Based on experiments at a gear efficiency test rig, the frictional power losses and bulk temperatures of DLC-coated gears are investigated, whereby load, speed, oil temperature and coatings are varied. Findings Experimental investigations at the gear efficiency test rig showed friction and bulk temperature reduction for all operating conditions of DLC-coated gears compared to uncoated gears. This effect was most pronounced for high load and high speed. A reduction of the mean gear coefficient of friction on average 25% and maximum 55% was found. A maximum reduction of bulk temperature of 15% was observed. Practical implications DLC-coated gears show a high potential for reducing friction and improving load-carrying capacity. However, the industrial implementation is restrained by the limited durability of coatings on gear flanks. Therefore, a further and overall consideration of key durability factors such as substrate material, pretreatment, coating parameters and gear geometry is necessary. Originality/value Thermal insulation effect of DLC coatings was shown by theoretical analyses and experimental investigations at model test rigs. Although trial tests on gears were conducted in literature, this study proves the friction reduction by DLC-coated gears for the first time systematically in terms of various operating conditions and coatings. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0257/

scholarly journals The Flex-OeCoS—a Novel Optically Accessible Test Rig for the Investigation of Advanced Combustion Processes under Engine-Like Conditions

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1794
Author(s):  
Bruno Schneider ◽  
Christian Schürch ◽  
Konstantinos Boulouchos ◽  
Stefan Herzig ◽  
Marc Hangartner ◽  
...  
Keyword(s):  
Combustion Chamber ◽  
Modular Design ◽  
Operating Conditions ◽  
Valve Train ◽  
Experimental Investigations ◽  
Test Rig ◽  
Optical Engine ◽  
Advanced Combustion ◽  
Wide Range ◽  
Combustion Processes

A new test rig has been designed, built and commissioned, and is now jointly pursued to facilitate experimental investigations into advanced combustion processes (i.e., dual fuel, multi-mode) under turbulent conditions at high, engine-like temperature and pressure levels. Based on a standard diesel engine block, it offers much improved optical access to the in-cylinder processes due to its separated and rotated arrangement of the compression volume and combustion chamber, respectively. A fully variable pneumatic valve train and the appropriate preconditioning of the intake air allows it to represent a wide range of engine-like in-cylinder conditions regarding pressures, temperatures and turbulence levels. The modular design of the test rig facilitates easy optimizations of the combustion chamber/cylinder head design regarding different experimental requirements. The name of the new test rig, Flex-OeCoS, denotes its Flexibility regarding Optical engine Combustion diagnostics and/or the development of corresponding Sensing devices and applications. Measurements regarding in-cylinder gas pressures, temperatures and the flow field under typical operating conditions are presented to complete the description and assessment of the new test rig.

Experimental Investigations to Use Splash Lubrication for High-Speed Gears

2017 ◽  
Vol 139 (6) ◽  
Author(s):  
A. Neurouth ◽  
C. Changenet ◽  
F. Ville ◽  
M. Octrue ◽  
E. Tinguy
Keyword(s):  
High Speed ◽  
Helical Gear ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Automotive Applications ◽  
Test Rig ◽  
Specific Test ◽  
Lubricant Oil ◽  
Speed Up ◽  
Run Up

In order to use electric motors which run up to 40,000 rpm in future automotive applications, this study aims to experimentally investigate if splash lubrication technique is worth considering for high-speed gears, i.e., for tangential gear speed up to 60 m/s. To this end, a specific test rig has been used to operate a single spur or helical gear in various operating conditions (lubricant, oil sump volume, temperature, etc.). Churning loss is measured and, as the fraction of air in the lubricant (namely, oil aeration) can be influential on this source of dissipation, a specific sensor is also employed for online monitoring of oil sump aeration. By inserting some moveable walls in the gearbox, it is demonstrated that churning losses and oil aeration can be significantly reduced by mounting these flanges at an appropriate distance to the gear lateral faces. Based on dimensional analysis, an engineering criterion is proposed to properly choose the clearance between the tested gear and the flanges.

Investigations of Road Wear Caused by Studded Tires

2014 ◽  
Vol 42 (1) ◽  
pp. 2-15
Author(s):  
Johannes Gültlinger ◽  
Frank Gauterin ◽  
Christian Brandau ◽  
Jan Schlittenhard ◽  
Burkhard Wies
Keyword(s):  
Traffic Safety ◽  
Test Bench ◽  
Operating Conditions ◽  
Test Method ◽  
Analytical Models ◽  
The Road ◽  
Driving Speed ◽  
Major Factors ◽  
Tire Friction ◽  
Variable Operating Conditions

ABSTRACT The use of studded tires has been a subject of controversy from the time they came into market. While studded tires contribute to traffic safety under severe winter conditions by increasing tire friction on icy roads, they also cause damage to the road surface when running on bare roads. Consequently, one of the main challenges in studded tire development is to reduce road wear while still ensuring a good grip on ice. Therefore, a research project was initiated to gain understanding about the mechanisms and influencing parameters involved in road wear by studded tires. A test method using the institute's internal drum test bench was developed. Furthermore, mechanisms causing road wear by studded tires were derived from basic analytical models. These mechanisms were used to identify the main parameters influencing road wear by studded tires. Using experimental results obtained with the test method developed, the expected influences were verified. Vehicle driving speed and stud mass were found to be major factors influencing road wear. This can be explained by the stud impact as a dominant mechanism. By means of the test method presented, quantified and comparable data for road wear caused by studded tires under controllable conditions can be obtained. The mechanisms allow predicting the influence of tire construction and variable operating conditions on road wear.

Experimental investigations to predict optimistic biodiesel(s) and its optimistic operating conditions by varying ignition delay period and fuel spray pressures for lower emissions and better performance

2020 ◽  
Vol 234 (19) ◽  
pp. 3890-3902
Author(s):  
Vishal V Patil ◽  
Ranjit S Patil
Keyword(s):  
Methyl Ester ◽  
Ignition Delay ◽  
Seed Oil ◽  
Delay Period ◽  
Operating Conditions ◽  
Experimental Investigations ◽  
Rubber Seed Oil ◽  
Rubber Seed ◽  
Neem Seed Oil ◽  
Ignition Delay Period

In this study, different characteristics of sustainable renewable biodiesels (those have a high potential of their production worldwide and in India) were compared with the characteristics of neat diesel to determine optimistic biodiesel for the diesel engine at 250 bar spray pressure. Optimistic fuel gives a comparatively lower level of emissions and better performance than other selected fuels in the study. Rubber seed oil methyl ester was investigated as an optimistic fuel among the other selected fuels such as sunflower oil methyl ester, neem seed oil methyl ester, and neat diesel. To enhance the performance characteristics and to further decrease the level of emission characteristics of fuel ROME, further experiments were conducted at higher spray (injection) pressures of 500 bar, 625 bar, and 750 bar with varying ignition delay period via varying its spray timings such as 8°, 13°, 18°, 23°, 28°, and 33° before top dead center. Spray pressure 250 bar at 23° before top dead center was investigated as an optimistic operating condition where fuel rubber seed oil methyl ester gives negligible hydrocarbon emissions (0.019 g/kW h) while its nitrogen oxide (NOX) emissions were about 70% lesser than those observed with neat diesel, respectively.

Modeling and Experimental Validation of the Effective Bulk Modulus of a Mixture of Hydraulic Oil and Air

2014 ◽  
Vol 136 (5) ◽  
Author(s):  
Hossein Gholizadeh ◽  
Doug Bitner ◽  
Richard Burton ◽  
Greg Schoenau
Keyword(s):  
Experimental Data ◽  
Bulk Modulus ◽  
Theoretical Models ◽  
Operating Conditions ◽  
Air Bubbles ◽  
Pressure Sensitivity ◽  
Hydraulic Oil ◽  
Effective Bulk Modulus ◽  
Experimental Apparatus ◽  
Major Factors

It is well known that the presence of entrained air bubbles in hydraulic oil can significantly reduce the effective bulk modulus of hydraulic oil. The effective bulk modulus of a mixture of oil and air as pressure changes is considerably different than when the oil and air are not mixed. Theoretical models have been proposed in the literature to simulate the pressure sensitivity of the effective bulk modulus of this mixture. However, limited amounts of experimental data are available to prove the validity of the models under various operating conditions. The major factors that affect pressure sensitivity of the effective bulk modulus of the mixture are the amount of air bubbles, their size and the distribution, and rate of compression of the mixture. An experimental apparatus was designed to investigate the effect of these variables on the effective bulk modulus of the mixture. The experimental results were compared with existing theoretical models, and it was found that the theoretical models only matched the experimental data under specific conditions. The purpose of this paper is to specify the conditions in which the current theoretical models can be used to represent the real behavior of the pressure sensitivity of the effective bulk modulus of the mixture. Additionally, a new theoretical model is proposed for situations where the current models fail to truly represent the experimental data.

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