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Thread ID: 93977 2008-10-09 00:44:00 Whatever happened to the NZ Wind generator business John W (523) PC World Chat
Post ID Timestamp Content User
710901 2008-10-09 00:44:00 This firm hit the news a few years back, using a Ground Based Wind turbine, sitting in the throat of a giant bell mouth velocity stack.

For all the world youd think the idea was to kind of RAM the air into the oriface to drive the turbine, but the design relied on the pressure differential as the air passed from the smaller to the larger opening, creating a suction and increasing its power output.

Naturally Ive forgotten the name of the business, I recall is it beng based in the NI somewhere.

Thanks

John in Mosgiel.
John W (523)
710902 2008-10-09 01:46:00 You cant increase its power output you cant make enrgy
There are 3 things at play

Temperature of air
Pressure of air
Velocity of air

You can change pressure and velocity with convergent or divergent ducts temp will go up and down but when ever you change them there is a small loss.

A turbine can use both speed of the air like impact on the blades or air pressure on the aerofoil of the blade to extract the power.
prefect (6291)
710903 2008-10-09 01:53:00 John I saw a doco a few months back on wind generation in cities. They are a bit like the wind generators we have in several parts of NZ except smaller and use the updraft in the City Streets. They create almost no noise unlike our big blade ones and point downwards towards the streets and mounted on high buildings.

Sounds like they would be good in the bigger cities where they would be more needed.

I spent last week in Mosgiel, no tall buildings there suitable, but Nellies was just as good as I remember it (food wise of course):-)
Bantu (52)
710904 2008-10-09 03:04:00 Like I said at the start, whats happened to the company, has it gone out of business or still plugging away, that all Im after really, someone to come up with the name, so I can go further.

:-)
John W (523)
710905 2008-10-09 04:24:00 sounds like what they have in Aussie. thermal rise turbine ?? sun heats the ground, hot air rises up through the stack pushing the blades. apparently effective if you have heaps of heat (ie desert). tweak'e (69)
710906 2008-10-09 04:59:00 You cant increase its power output you cant make enrgy
There are 3 things at play

Temperature of air
Pressure of air
Velocity of air

You can change pressure and velocity with convergent or divergent ducts temp will go up and down but when ever you change them there is a small loss.

A turbine can use both speed of the air like impact on the blades or air pressure on the aerofoil of the blade to extract the power.

But if you put it on a conveyor belt that moves at EXACTLY the same speed..... :D
johcar (6283)
710907 2008-10-09 05:13:00 That could fly . . . R2x1 (4628)
710908 2008-10-09 07:25:00 You cant increase its power output you cant make enrgy
There are 3 things at play

Temperature of air
Pressure of air
Velocity of air

You can change pressure and velocity with convergent or divergent ducts temp will go up and down but when ever you change them there is a small loss.

A turbine can use both speed of the air like impact on the blades or air pressure on the aerofoil of the blade to extract the power.

That is a rather too simplistic or puristic stance which doesn't take all factors into account.

A ducted turbine or fan can increase blading efficiency/reduce blade losses by advantageously modifying the air speed relative to the blade speed, also increase air flow, and hence extract more power from the air stream, or, in the case of a ducted fan, produce more thrust.

A quick Google shows quite a lot of work on ducted turbines, then of course ducted fans have been around for yonks, especially relating to aircaft engines.

www.google.co.nz

The NZ firm is probably Vortec Energy Ltd, here is a paper on the topic:

www.ipenz.org.nz
Terry Porritt (14)
710909 2008-10-09 18:07:00 That is a rather too simplistic or puristic stance which doesn't take all factors into account.

A ducted turbine or fan can increase blading efficiency/reduce blade losses by advantageously modifying the air speed relative to the blade speed, also increase air flow, and hence extract more power from the air stream, or, in the case of a ducted fan, produce more thrust.

A quick Google shows quite a lot of work on ducted turbines, then of course ducted fans have been around for yonks, especially relating to aircraft engines.

www.google.co.nz

The NZ firm is probably Vortec Energy Ltd, here is a paper on the topic:

www.ipenz.org.nz

Good to see you answered the mans question Ter.
I see you couldn't resist the temptation to tell us how things work,we are all subject to vanity,so not to worry.
Cicero (40)
710910 2008-10-10 05:06:00 Thanks, Vortec Energy Ltd was the name of the firm I was after.

:-)

John.
John W (523)
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