Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
A comparison was made between computer model predictions of gear dynamic behaviour and experimental results. The experimental data were derived from the NASA near noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the DSTO Aeronautical Research Laboratory's gear dynamics code for a matrix of 28 load- speed points. At high torque the peak dynamic load predictions agree with experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light-torque, high-speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple-tooth contact region.
A Comparison Between Theoretical Prediction and Experimental Measurement of the Dynamic Behaviour of Spur Gears
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
A comparison was made between computer model predictions of gear dynamic behaviour and experimental results. The experimental data were derived from the NASA near noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the DSTO Aeronautical Research Laboratory's gear dynamics code for a matrix of 28 load- speed points. At high torque the peak dynamic load predictions agree with experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light-torque, high-speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple-tooth contact region.
Publisher:
ISBN:
Category :
Languages : en
Pages : 10
Book Description
A comparison was made between computer model predictions of gear dynamic behaviour and experimental results. The experimental data were derived from the NASA near noise rig, which was used to record dynamic tooth loads and vibration. The experimental results were compared with predictions from the DSTO Aeronautical Research Laboratory's gear dynamics code for a matrix of 28 load- speed points. At high torque the peak dynamic load predictions agree with experimental results with an average error of 5 percent in the speed range 800 to 6000 rpm. Tooth separation (or bounce), which was observed in the experimental data for light-torque, high-speed conditions, was simulated by the computer model. The model was also successful in simulating the degree of load sharing between gear teeth in the multiple-tooth contact region.
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 602
Book Description
Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Proceedings of the ... International Power Transmission and Gearing Conference
International Aerospace Abstracts
An Experimental and Theoretical Study of Subharmonic Resonances of a Spur Gear Pair
Author: Cihan Alper Celikay
Publisher:
ISBN:
Category : Gearing
Languages : en
Pages : 0
Book Description
Nonlinear dynamic behavior of a spur gear pair has been a major topic in both gear dynamics and nonlinear vibration fields. A spur gear pair can exhibit a wide range of nonlinear behavior primarily due to its backlash and periodically time-varying mesh stiffness. While a number of theoretical studies pointed to the possibility of severe subharmonic resonances at integer multiples of the primary resonance of the gear pair, past experimental investigations focused overwhelmingly on the behavior within the speed ranges where primary and super-harmonic resonance peaks occur. There has been very little experimental evidence of such subharmonic resonances, perhaps because such investigations require very high-speed experiments pushing the limits of test machine and measurement system capabilities. In this study, a test gear pair design is implemented to reduce the primary resonance frequency significantly such that the first three subharmonic resonances can be studied using an existing test machine and a conventional gear transmission error measurement method. Transient and steady-state data are collected at different transmitted torque values to show softening type of nonlinear behavior at super-harmonic and primary resonance peaks along with a well-defined first subharmonic resonance peak dictated by period-2 motions. Other subharmonic motions up to period-4 are also demonstrated experimentally. At the end, two different dynamic models, a discrete torsional model and a deformable-body model, are employed to simulate the experiments, focusing on the subharmonic resonance regions. Both models are shown to be effective in correlating to experiments.
Publisher:
ISBN:
Category : Gearing
Languages : en
Pages : 0
Book Description
Nonlinear dynamic behavior of a spur gear pair has been a major topic in both gear dynamics and nonlinear vibration fields. A spur gear pair can exhibit a wide range of nonlinear behavior primarily due to its backlash and periodically time-varying mesh stiffness. While a number of theoretical studies pointed to the possibility of severe subharmonic resonances at integer multiples of the primary resonance of the gear pair, past experimental investigations focused overwhelmingly on the behavior within the speed ranges where primary and super-harmonic resonance peaks occur. There has been very little experimental evidence of such subharmonic resonances, perhaps because such investigations require very high-speed experiments pushing the limits of test machine and measurement system capabilities. In this study, a test gear pair design is implemented to reduce the primary resonance frequency significantly such that the first three subharmonic resonances can be studied using an existing test machine and a conventional gear transmission error measurement method. Transient and steady-state data are collected at different transmitted torque values to show softening type of nonlinear behavior at super-harmonic and primary resonance peaks along with a well-defined first subharmonic resonance peak dictated by period-2 motions. Other subharmonic motions up to period-4 are also demonstrated experimentally. At the end, two different dynamic models, a discrete torsional model and a deformable-body model, are employed to simulate the experiments, focusing on the subharmonic resonance regions. Both models are shown to be effective in correlating to experiments.
An Experimental Study of the Dynamic Response of Spur Gears Having Tooth Index Errors
Author: Allen Y. Sun
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
While there are numerous theoretical and experimental investigations of dynamic behavior of gear pairs of higher quality grades, very little is known about the same when certain classes of manufacturing errors are present. This study aims at investigating the effects of tooth index errors, one of the most common types of manufacturing errors. Using the changes in stresses along the tooth root regions as the metric, an experimental study is executed here to (i) establish a baseline dynamic behavior under no tangible index error and (ii) characterize the changes caused by tightly-controlled intentional index errors to this baseline dynamic behavior. For this, various gears having different forms of index errors are paired with an instrumented gear having no such errors. For each gear pair, tests are performed within wide ranges of torque and speed. A data processing scheme is proposed to normalize the measured stress signals to multiplication factor. It is shown that the baseline dynamic response represented solely by the dynamic stress factor is altered significantly by transient vibrations induced by the indexing errors, in some cases fully altering the baseline dynamic behavior and increasing the stress multiplication factors significantly. The experimental database formed in this study is expected to guide much needed theoretical studies on this topic.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
While there are numerous theoretical and experimental investigations of dynamic behavior of gear pairs of higher quality grades, very little is known about the same when certain classes of manufacturing errors are present. This study aims at investigating the effects of tooth index errors, one of the most common types of manufacturing errors. Using the changes in stresses along the tooth root regions as the metric, an experimental study is executed here to (i) establish a baseline dynamic behavior under no tangible index error and (ii) characterize the changes caused by tightly-controlled intentional index errors to this baseline dynamic behavior. For this, various gears having different forms of index errors are paired with an instrumented gear having no such errors. For each gear pair, tests are performed within wide ranges of torque and speed. A data processing scheme is proposed to normalize the measured stress signals to multiplication factor. It is shown that the baseline dynamic response represented solely by the dynamic stress factor is altered significantly by transient vibrations induced by the indexing errors, in some cases fully altering the baseline dynamic behavior and increasing the stress multiplication factors significantly. The experimental database formed in this study is expected to guide much needed theoretical studies on this topic.
Monthly Catalog of United States Government Publications
Author: United States. Superintendent of Documents
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1072
Book Description
February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1072
Book Description
February issue includes Appendix entitled Directory of United States Government periodicals and subscription publications; September issue includes List of depository libraries; June and December issues include semiannual index
Monthly Catalogue, United States Public Documents
Author:
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1786
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 1786
Book Description