Control of screw pile installation to optimise performance for offshore energy applications

Existing guidance on the installation of screw piles suggest that they should be installed in a pitch-matched manner to avoid disturbance to the soil which may have a detrimental effect on the in-service performance of the pile. Recent insights from centrifuge modelling have shown that installing screw piles in this way requires large vertical compressive (or crowd) forces, which is inconsistent with the common assumption that screw piles pull themselves into the ground requiring minimal vertical compressive force. In this paper, through the use of the Discrete Element Method (DEM), the effects of advancement ratio, i.e. the ratio between the vertical displacement per rotation to the geometric pitch of the helix of the screw pile helix, on the installation resistance and in-service capacity of a screw pile is investigated. The findings are further used to assess the applicability of empirical torque capacity correlation factors for large diameter screw piles. The results of the investigation show that it is possible to reduce the required vertical compressive installation force by 96% by reducing the advancement ratio and that although over-flighting a screw pile can decrease the subsequent compressive capacity, it appears to increase the tensile capacity significantly.

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Cost Effective Synthesis and Fabrication of Phase-Pure Kesterite Cu2-xZn1.3SnS4 P-type Absorber Layer Thin Films by Solvent Based Process Technique for Photovoltaic Solar Energy Applications

International Journal of Emerging Research in Management and Technology ◽

10.23956/ijermt.v7i4.5 ◽

2018 ◽

Vol 7 (4) ◽

pp. 36

Author(s):

B. Khadambari ◽

S. S. Bhattacharya

Keyword(s):

Solar Energy ◽

Renewable Energy Sources ◽

Cost Effective ◽

Absorber Layer ◽

Window Layer ◽

Energy Applications ◽

Process Technique ◽

Absorber Material ◽

Effective Synthesis ◽

P Type

Solar has become one of the fastest growing renewable energy sources. With the push towards sustainability it is an excellent solution to resolve the issue of our diminishing finite resources. Alternative photovoltaic systems are of much importance to utilize solar energy efficiently. The Cu-chalcopyrite compounds CuInS2 and CuInSe2 and their alloys provide absorber material of high absorption coefficients of the order of 105 cm-1. Cu2ZnSnS4 (CZTS) is more promising material for photovoltaic applications as Zn and Sn are abundant materials of earth’s crust. Further, the preparation of CZTS-ink facilitates the production of flexible solar cells. The device can be designed with Al doped ZnO as the front contact, n-type window layer (e.g. intrinsic ZnO); an n-type thin film buffer layer (e.g. CdS) and a p-type CZTS absorber layer with Molybdenum (Mo) substrate as back contact. In this study, CZTS films were synthesized by a non-vaccum solvent based process technique from a molecular-ink using a non toxic eco-friendly solvent dimethyl sulfoxide (DMSO). The deposited CZTS films were optimized and characterized by XRD, UV-visible spectroscopy and SEM.

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Lossless Dynamic Models of the Quasi-Z-Source Converter Family

Scientific Journal of Riga Technical University Power and Electrical Engineering ◽

10.2478/v10144-011-0013-y ◽

2011 ◽

Vol 29 (1) ◽

pp. 73-78 ◽

Cited By ~ 1

Author(s):

Dmitri Vinnikov ◽

Oleksandr Husev ◽

Indrek Roasto

Keyword(s):

Renewable Energy ◽

Dynamic Models ◽

Energy Applications

Lossless Dynamic Models of the Quasi-Z-Source Converter FamilyThis paper is devoted to the quasi-Z-source (qZS) converter family. Recently, the qZS-converters have attracted attention because of their specific properties of voltage boost and buck functions with a single switching stage, which could be especially beneficial in renewable energy applications. As main representatives of the qZS-converter family, the traditional quasi-Z-source inverter as well as two novel extended boost quasi-Z-source inverters are discussed. Lossless dynamic models of these topologies are presented and analyzed.

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Energy applications

Physics Subject Headings (PhySH) ◽

10.29172/e6586efa-1454-4ae2-9407-f4ca0d9322da ◽

2018 ◽

Keyword(s):

Energy Applications

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Proceedings of the International Conference on Electrocatalysis for Energy Applications and Sustainable Chemicals

10.29363/nanoge.ecocat.2020.000 ◽

2020 ◽

Keyword(s):

International Conference ◽

Energy Applications

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Effect of Pile and Load Inclination on the Pile Resistance In both Compression and Tension

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol2.iss1.21 ◽

2014 ◽

Vol 2 (1) ◽

pp. 11-29

Author(s):

Ahmad Jabber Hussain ◽

Alaa Dawood Salman ◽

. Nazar Hassan Mohammad

Keyword(s):

Bearing Capacity ◽

Inclination Angle ◽

Theoretical Study ◽

Pile Installation ◽

Soil Failure ◽

Inclined Pile ◽

Uplift Resistance ◽

Lift Forces ◽

Batter Piles ◽

Pile Resistance

According to this theoretical study which was about loading of piles under different condition of loading (compression and up-lift forces ) and for deferent pile installation (vertical and inclined pile ) by which it called (positive batter pile ) when the inclination of the load and pile is in the same direction and called (negative batter pile) when the inclination of load is opposite to the pile inclination, and from studying these cases the results of analysis can be summarize in the flowing points: 1-Variation of load inclination on piles effects on the bearing capacity and uplift resistance. It was found that bearing capacity of the piles increase with increasing of load inclination up to the inclination angle (37.5ͦ) which represents the maximum bearing capacity and then the bearing capacity decrease with increasing of load inclination. 2- Variation of batter pile affects the bearing capacity of the pile and up-lift resistance. by which equivalent angle will be used as result between the load and piles inclination and this angle will be used in calculation of piles resistance . 3- It was noticed the shape of soil failure is highly affected by the inclination of pile. The shape of failure for the soil which is in contact with pile and this include (vertical and batter piles) is highly affected by the angle of inclination.

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