Research on The Dynamic Characteristics of Relaxed Static Stability Control Aircraft

Abstract. In this study, the spatial and temporal distributions of dynamic and synoptic characteristics of a selection of 32 deep baroclinic depressions have been investigated. The study covers the cold period months of November till March, in the period from 1 November 1986 to 31 March 2003. For the needs of the study, several synoptic characteristics of these depressions have been extracted. Also, several dynamic characteristics during the evolution of the depressions were studied: relative vorticity, divergence, vertical motion and a static stability parameter. The results are presented in the form of isobaric distributions over, three tropospheric isobaric levels, namely the lower 850 hPa, the middle 500 hPa and the upper 300 hPa.

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Influences of weaving parameters on dynamic characteristics and stability control of the droplet transfer in arc-weaving P-GMAW process

The International Journal of Advanced Manufacturing Technology ◽

10.1007/s00170-021-08193-x ◽

2022 ◽

Author(s):

Di Wu ◽

Yuxi Chen ◽

Huabin Chen ◽

Shanben Chen

Keyword(s):

Dynamic Characteristics ◽

Stability Control ◽

Droplet Transfer

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Static, stability and dynamic characteristics of asymmetric bi-directional functionally graded sandwich tapered elastic arches in thermal environment

European Journal of Mechanics - A/Solids ◽

10.1016/j.euromechsol.2021.104447 ◽

2021 ◽

pp. 104447

Author(s):

Sundaramoorthy Rajasekaran ◽

Hossein Bakhshi Khaniki ◽

Mergen H. Ghayesh

Keyword(s):

Dynamic Characteristics ◽

Thermal Environment ◽

Static Stability ◽

Functionally Graded

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What Controls the Mean Depth of the PBL?

Journal of Climate ◽

10.1175/jcli3417.1 ◽

2005 ◽

Vol 18 (16) ◽

pp. 3157-3172 ◽

Cited By ~ 80

Author(s):

Brian Medeiros ◽

Alex Hall ◽

Bjorn Stevens

Keyword(s):

Los Angeles ◽

Boundary Layers ◽

Large Scale ◽

Static Stability ◽

Stability Control ◽

Surface Fluxes ◽

Free Atmosphere ◽

Convective Boundary ◽

Consistent Treatment ◽

The University

Abstract The depth of the planetary boundary layer (PBL) is a climatologically important quantity that has received little attention on regional to global scales. Here a 10-yr climatology of PBL depth from the University of California, Los Angeles (UCLA) atmospheric GCM is analyzed using the PBL mass budget. Based on the dominant physical processes, several PBL regimes are identified. These regimes tend to exhibit large-scale geographic organization. Locally generated buoyancy fluxes and static stability control PBL depth nearly everywhere, though convective mass flux has a large influence at tropical marine locations. Virtually all geographical variability in PBL depth can be linearly related to these quantities. While dry convective boundary layers dominate over land, stratocumulus-topped boundary layers are most common over ocean. This division of regimes leads to a dramatic land–sea contrast in PBL depth. Diurnal effects keep mean PBL depth over land shallow despite large daytime surface fluxes. The contrast arises because the large daily exchange of heat and mass between the PBL and free atmosphere over land is not present over the ocean, where mixing is accomplished by turbulent entrainment. Consistent treatment of remnant air from the deep, daytime PBL is necessary for proper representation of this diurnal behavior over land. Many locations exhibit seasonal shifts in PBL regime related to changes in PBL clouds. These shifts are controlled by seasonal variations in buoyancy flux and static stability.

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Influences of Weaving Parameters on Dynamic Characteristics and Stability Control of the Droplet Transfer in Arc-Weaving P-GMAW Process

10.21203/rs.3.rs-747670/v1 ◽

2021 ◽

Author(s):

Di Wu ◽

Yuxi Chen ◽

Huabin CHEN ◽

Shanben Chen

Keyword(s):

Dynamic Characteristics ◽

High Speed ◽

Gas Metal Arc Welding ◽

Welding Process ◽

Stability Control ◽

Force Balance ◽

Root Penetration ◽

High Speed Photography ◽

Force Model ◽

Droplet Transfer

Abstract The dynamic characteristics of droplet transfer is extremely complicated with the combined effects of gravity force and weaving motion during the weaving vertical-up welding on thick plate. In this paper, we firstly observed the droplet transfer behavior under various weaving parameters with high-speed photography and electrical signals during pulsed gas metal arc welding (P-GMAW). Then we investigated the influences of different weaving parameters on the arc shape and molten pool as well as droplet characteristics. By establishing a novel weaving-force model based on static-force balance theory (SFBT), we further revealed the drop transfer mechanism in weaving P-GMAW process. Extensive experimental results demonstrated that the suitable weaving parameters could effectively improve the droplet transfer stability and suppress welding defects including incomplete root penetration and lack of sidewall fusion. The findings of this paper will provide a basis for enhancing the welding process stability and obtaining a high-quality weld joint.

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