Optimal Design of a Vibration Isolation Mount Using Physical Programming

1999 ◽  
Vol 121 (2) ◽  
pp. 171-178 ◽  
Author(s):  
Bruce H. Wilson ◽  
Cem Erin ◽  
Achille Messac
Keyword(s):  
Vibration Isolation ◽  
Integrated Design ◽  
Design Metrics ◽  
New Model ◽  
Physical Programming ◽  
Optimization Framework ◽  
Simultaneous Control ◽  
Research Environments ◽  
Physical Insight ◽  
Overall Performance

Vibration isolation tables find application in diverse production and research environments. The structure of a table is such that a designer is forced to compromise among design metrics such as transmissibility, force-disturbance rejection, and controller effort. As both structural and controller parameters impact these design metrics, we chose to perform simultaneous control-structure integrated design (CSID) to optimize the overall performance. We employed a new model that enhances physical insight and used physical programming as the optimization framework. We explored several design scenarios and effectively uncovered the appropriate compromises among the competing objectives. The results highlight the utility of the new model in this design context and the usefulness of physical programming in performing simultaneous CSID.

Numerical Simulation Studies on the Performance of a Diffuser Attached With Last Stage Compressor Outlet Guide Vanes

2019 ◽  
Author(s):  
A. T. Sriram
Keyword(s):  
High Speed ◽  
Guide Vane ◽  
Integrated Design ◽  
Computational Domain ◽  
Simulation Studies ◽  
Allowable Limit ◽  
Guide Vanes ◽  
Compressor Rotor ◽  
Overall Performance ◽  
Last Stage

Abstract Combustor pre-diffuser is an important element connecting the compressor and combustor. The design of pre-diffuser should be in such a way that the flow velocity to be within allowable limit to hold the flame in the combustor and also it should recover pressure with less amount of total pressure loss. The general practice is to design the compressor and combustor separately for their performance. However, integrated design of outlet guide vanes and pre-diffuser is given importance, on nowadays, to improve the overall performance. Basically, the outlet guide vane blades are modified to improve the performance. In the present work, numerical simulations studies have been carried out for a well-known high speed compressor, NASA Stage 37, to identify the influence of blade parameters. The computational domain consists of compressor rotor, stator and combustor pre-diffuser. The stator blades serve as outlet guide vanes. In literature, studies were shown that there is improvement in introducing blade sweep. Also, blade lean was shown some advantages for the case of a pre-diffuser with axial inlet and radial outlet with flow turning. However, in the present case of axial inlet and axial outlet, blade lean has not shown improvement in the performance. A diffuser showing slightly unstable condition in the conventional design, Area Ratio (AR) of 1.5 in the present case, has shown improvement with the presence of blade sweep.

Control integrated design of active deformation and intrinsic elasticity for morphing waverider

2016 ◽  
Vol 23 (7) ◽  
pp. 1073-1085
Author(s):  
Yanbin Liu ◽  
Bing Hua
Keyword(s):  
Integrated Design ◽  
Parametric Model ◽  
The Other ◽  
Control Law ◽  
Lightweight Construction ◽  
Active Deformation ◽  
Trade Off ◽  
Flight Range ◽  
Overall Performance ◽  
Elastic Dynamics

The hypersonic waverider using the morphing configuration can improve the overall performance and broaden the flight range. On the other hand, the hypersonic waverider belongs to the lightweight construction, leading to the presence of the intrinsic elasticity. As a result, the integrated consideration of the active deformation and elastic action is important for the morphing waverider to realize global optimization. In this paper, the contro-integrated design methods are proposed for the morphing waverider to implement the trade-off analysis between the active deformation and intrinsic elasticity. First, the parametric model is built to describe the hypersonic flight characteristics. Then, the elastic dynamics is introduced to quantify the coupling responses associated with the angle of attack and elevon deflection. Furthermore, the integrated design is considered for the active deformation and inherent elastic action, and also the control law is designed to suppress the active and passive morphing disturbances. Finally, the simulation is conducted to test the effectiveness of the presented methods for the morphing waverider.

scholarly journals Influence of Flexible Foundation on Isolator Wave Effects

1996 ◽  
Vol 3 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Ye-Ping Xiong ◽  
Kong-Jie Song ◽  
Xing Ai
Keyword(s):  
Closed Form ◽  
Vibration Isolation ◽  
Response Ratio ◽  
New Model ◽  
Closed Form Solutions ◽  
Special Cases ◽  
Wave Effects ◽  
Rigid Mass ◽  
Isolation Systems ◽  
Flexible Foundation

This article deals with the interaction between wave effects in mounts and resonances of foundations inflexible vibration isolation systems. A new model is proposed that is represented as a rigid mass supported by two linear unidirectional isolators on a flexible foundation beam, whose closed-form solutions for transmissibility and response ratio are then obtained, with which the influence of wave effects coupled with the flexibility of the foundation on the effectiveness of isolation is discussed. The wave effects on flexible isolation systems are analyzed under various parametric conditions and compared with those in rigid systems. In addition, several special cases are presented to show the transition between various limiting cases. Some approaches to control wave effects are also proposed.

Enhanced External Aerodynamic Performance of a Generic Combustor Using An Integrated OGV/Prediffuser Design Technique

2006 ◽  
Vol 129 (1) ◽  
pp. 80-87 ◽  
Author(s):  
A. Duncan Walker ◽  
Jon F. Carrotte ◽  
James J. McGuirk
Keyword(s):  
Integrated Design ◽  
Boundary Layer Separation ◽  
Aerodynamic Performance ◽  
Final Report ◽  
Experimental Measurements ◽  
Blade Shape ◽  
Flow Quality ◽  
Overall Performance ◽  
Loss Coefficients

In this paper we use experimental measurements to characterize the extent that improved the external aerodynamic performance (reduced total pressure loss, increased flow quality) of a gas-turbine combustion system may be achieved by adopting an integrated OGV/prediffuser technique. Two OGV/prediffuser combinations were tested. The first is a datum design corresponding to a conventional design approach, where the OGV and prediffuser are essentially designed in isolation. The second is an “integrated” design where the OGV blade shape has been modified, following recommendations of earlier CFD work (Final Report No. TT03R01, 2003), to produce a secondary flow/wake structure that allows the prediffuser to operate at a higher area ratio without boundary layer separation. This is demonstrated to increase static pressure recovery and reduce dump losses. Experimental measurements are presented on a fully annular rig. Several traverse planes are used to gather five-hole probe data that allow the flow structure through the OGV, at the inlet and exit of the prediffuser, and in the inner/outer annulus supply ducts to be examined. Both overall performance measures (loss coefficients) and measures of flow uniformity and quality are used to demonstrate that the integrated design is superior.

A new model for the vibration isolation via pile rows consisting of infinite number of piles

2012 ◽  
Vol 37 (15) ◽  
pp. 2394-2426 ◽  
Author(s):  
Jian-Fei Lu ◽  
Dong-Sheng Jeng ◽  
Jian-Wei Wan ◽  
Ji-Sheng Zhang
Keyword(s):  
Infinite Number ◽  
Vibration Isolation ◽  
New Model
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