Featured Research

from universities, journals, and other organizations

A model designed to balance the bolting load of wind turbines developed

Date:
August 14, 2012
Source:
Basque Research
Summary:
A researcher has built a simplified simulation model for wind turbines. All one has to do is enter the characteristics that the tower and its parts will have, and in a matter of seconds the model predicts the load that has to be given to each of the bolts, which leads to great advantages in the construction and maintenance process.

Mikel Abasolo, author of the thesis.
Credit: Luis Jauregialtzo / Argazki Press

Mikel Abasolo, a researcher of the University of the Basque Country (UPV/EHU), has built a simplified simulation model for wind turbines. All one has to do is enter the characteristics that the tower and its parts will have, and in a matter of seconds the model predicts the load that has to be given to each of the bolts, which leads to great advantages in the construction and maintenance process. And it is a fact that in installations of such large dimensions, it is customary to have to adjust the bolts over and over again to balance the load.

But this model enables these data to be known before the building begins. Abasolo has done this work in the ADM (Mechanical Analysis and Design) group of the Faculty of Engineering in Bilbao, in the line corresponding to renewable energies. He has subsequently defended his thesis entitled Metamodelo para la simulación y optimización de secuencias de atornillado en uniones de torres de aerogenerador (Meta-model for the simulation and optimisation of bolting sequences in wind turbine tower joints).

Owing to their great height, wind turbine towers are built in two or three parts and are subsequently bolted together. However, joining elements of such dimensions and quantities of bolts is very complex. "The aim is that all the bolts should have the same load so that they all work equally. But in practice, achieving this uniformity is no easy task. In an adjustment sequence, when you tighten one bolt, the previous ones lose part of their load," explains Abasolo. So, if in one sequence a load of 100 points (for example) is assigned to all the bolts one by one, by the end of the sequence most of them will not remain the same because when one is adjusted, the previous ones lose load. According to the researcher, only a few bolts will continue to have 100 points while the rest will be below that: "So, what do you do in order to keep all the bolts at the level of 100 points? You adjust them as many times as necessary (normally between three and four times), until you get a uniform load of 100 points on all of them. Naturally, this means a loss of time and money."

An exact load for each bolt

This is the reason why this simplified model is so valuable, because it can predict what load has to be apportioned to each bolt at the moment when the installation is assembled, so that by the end of the process the load ends up being uniform. You have to input into the model data like tube geometry, the exterior and interior diameter, the metrics and resistance of the bolts or the final load you want to achieve; this is enough so that in a matter of seconds the result that fits the circumstances is achieved. "The load that has to be assigned to each bolt will be greater than what one wants to obtain at the end, because it is lost in the sequence. If one wants to achieve a final load of 100, some will have to be assigned 110 and others 120, etc. The model tells us the exact load that has to be given to each bolt. This way the final load will be achieved in one single step, or, in two, at the most," asserts Abasolo.

This model can also be applied to maintenance tasks. As time goes by, the bolts of the wind turbine towers loosen, and just as when they are built, they have to be adjusted over and over again until the load is uniform once again, which means that here, too, a lot of time and money is lost.

As Abasolo explains, this simplified model is totally pioneering, since until now nothing like it geared towards wind turbines has been done: "Similar things have been done for pressure pipes, but there was nothing with respect to wind turbine joints. So we have taken advantage of a methodology never used before in this area." The model has yielded good results in a number of simulations that have been carried out over commercial programs, and has therefore been found to be useful. This researcher believes that in the future it could have applications as far as the market is concerned.


Story Source:

The above story is based on materials provided by Basque Research. Note: Materials may be edited for content and length.


Cite This Page:

Basque Research. "A model designed to balance the bolting load of wind turbines developed." ScienceDaily. ScienceDaily, 14 August 2012. <www.sciencedaily.com/releases/2012/08/120814100249.htm>.
Basque Research. (2012, August 14). A model designed to balance the bolting load of wind turbines developed. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2012/08/120814100249.htm
Basque Research. "A model designed to balance the bolting load of wind turbines developed." ScienceDaily. www.sciencedaily.com/releases/2012/08/120814100249.htm (accessed September 20, 2014).

Share This



More Matter & Energy News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

What This MIT Sensor Could Mean For The Future Of Robotics

What This MIT Sensor Could Mean For The Future Of Robotics

Newsy (Sep. 20, 2014) — MIT researchers developed a light-based sensor that gives robots 100 times the sensitivity of a human finger, allowing for "unprecedented dexterity." Video provided by Newsy
Powered by NewsLook.com
MIT BioSuit A New Take On Traditional Spacesuits

MIT BioSuit A New Take On Traditional Spacesuits

Newsy (Sep. 19, 2014) — The MIT BioSuit could be an alternative to big, bulky traditional spacesuits, but the concept needs some work. Video provided by Newsy
Powered by NewsLook.com
New Music With Recycled Instruments at Colombia Fest

New Music With Recycled Instruments at Colombia Fest

AFP (Sep. 19, 2014) — Jars, bottles, caps and even a pizza box, recovered from the trash, were the elements used by four musical groups at the "RSFEST2014 Sonorities Recycling Festival", in Colombian city of Cali. Duration: 00:49 Video provided by AFP
Powered by NewsLook.com
Virtual Reality Headsets Unveiled at Tokyo Game Show

Virtual Reality Headsets Unveiled at Tokyo Game Show

AFP (Sep. 18, 2014) — Several companies unveiled virtual reality headsets at the Tokyo Game Show, Asia's largest digital entertainment exhibition. Duration: 00:48 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins