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Author Topic: Location of Kort nozzles on a twin screw Tug  (Read 1519 times)

Fastfaz

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Location of Kort nozzles on a twin screw Tug
« on: March 16, 2016, 08:52:41 PM »

     Hello everyone,
         Regarding the distance from the stern to the rear face of Kort nozzles (usually approx. 2 inches/50mm from the stern of the tug to the rear face of the Kort nozzle) has anyone ever tried altering the hull shape cutting it so that the Kort nozzles are approx. 1/3rd of the boats length in from the stern i.e. if the boat is 36 inches long Korts located 12 inches in from the stern? I am curious as to whether doing this would make the boat turn and manoeuvre more sharply as in the longer the boat its harder to turn etc. I am interested to know if this would work or make things worse, comparing short wheelbase's in cars and motorbikes the shorter the wheelbase makes for better turning and handling but does make a motorbike more lively/twitchy in a straight line. Answers on a postcard, food for thought.
      Cheers,
           Faz. {:-{ {:-{ {:-{ {:-{ {:-{ {:-{ {:-{
     
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Starspider

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Re: Location of Kort nozzles on a twin screw Tug
« Reply #1 on: March 16, 2016, 10:58:02 PM »

I would think that the model would have a tendency to crab sideways as she tried to turn, due to the drag of the hull behind the Korts. Just my first thoughts  :-X
Colin

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derekwarner

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Re: Location of Kort nozzles on a twin screw Tug
« Reply #2 on: March 17, 2016, 12:22:22 AM »

Faz.....by cutting into the hull to 'locate the Korts nozzles 12 inches in from the stern', you are also reducing the block co-efficient of the hull which proportionally reduces the volume & as such the displacement

So without any other ballast compensation the bow would dip & the stern rise....the nozzles may even be partly above the waterline  O0

Derek
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Derek Warner

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Captain fizz

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Re: Location of Kort nozzles on a twin screw Tug
« Reply #3 on: March 17, 2016, 01:04:02 PM »

You would also likely end up with a very steep angle on the prop shafts which will try to lift the stern.
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Netleyned

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Re: Location of Kort nozzles on a twin screw Tug
« Reply #4 on: March 17, 2016, 03:03:18 PM »

The Korts would have to be angled downwards to accommodate the props.
Going astern should be fun :embarrassed:
The pivot point would be near the bows.
If it was a good idea it would be in use on 1/1 scale models %%


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