Friday, March 27, 2015

6 - A video link to a group of student doing WIG project in Melbourne

https://www.youtube.com/watch?v=VOqUS83yUkI

My comment is I think they shouldn't have picked the Ekranoplane design.
I don't think their design is a success.

But during testing, they actually used a flying camera to record footage. I think that's a very nice idea.
I think it's time to submit another request form, before they cut our budget.

Saturday, March 14, 2015

5 - Doing a Model on the Pi day

Yes, let me explain why is today the Pi Day.
Not pie, but the maths symbol, Pi.


The first 10 digits of π = 3.141592653
A great coincidence with the calendar, march.14.2015.9am.26min.53sec
Where was I? At the gym, thinking about the model design that I'm going to do later.

4 - Playing with Styrofoam (11 Mar 2015)

Friday, March 6, 2015

3 - Some thoughts on payload and design



The X-113B is a reverse delta wing design, and this is the design that our senior project team adopted in their model.
What makes me wonder is why did they choose a design that is so sensitive of the location of C.G.
Because of this matter, the payload is likely to have a limit and it can only be positioned at one area, area in front of the wing.
This restrict the usage of WIG to a commercial passenger carrier only. (This is how I feel, may not be true)




So I explored and read about some other design like the Orlyonok designed by Mr. Aleexv, this WIG craft is really fascinating.
The craft is able to achieve height that is rather above the water surface, but seems like it is still in the ground effect zone.
It is huge, the whole fuselage seems to be able to be used for carrying payload.
What's interesting is that there are actually 2 engine at the front to feed air for the wing in order for the plane to be lifted easily during take off.
This is a different design from the classic WIG by Dr. Alexander Lippisch. The wing on the Orlyonok looks like commercial aircraft but with smaller aspect ratio.

I liked this design because the payload seems satisfactory.
However, our project is only using propeller engine as we are not aiming to design a high speed WIG craft, we are not likely to adopt this design.
(But it's really cool)



So

Mr Hanno Fischer, a co-worker of Dr Lippisch, seems to be very concerned with improving the take off ability of the reverse delta wing design.
Because he came up with the idea of getting a part of the propeller slip-stream and guide it under the Katamaran fuselage to build up a static air cushion to assist the take-off, and according to FF(the company), this creates 80% of the crafts weight as lift while speed is still 0.



The WSH-500 is the first large reverse delta wing WIG craft and they are able to do so because they adopted Mr Fischer's idea.
Wingship company actually hired him as a technical advisor.

2 - Improved Model made from Styrofoam



So Mengzhen always has a way in giving us surprises.
She made an improved model of the one we made last Friday.
The model was made to be simple which only contains the wing, the tail and the structure that joins the two. We hope to understand a little bit more of the aerodynamics of the plane in this way.


The design is very creative. Below are some of its features.
1) Functions of end plates and structure has been merged.
2) Very little friction with contact surface as the tip of the structure has been sharpened and covered with transparent tape.
3) Adjustment tail allows the height of the tail to be adjusted when necessary


But the model wasn't able to sustain it's flight, why?
A possible reason is that the main wing is too flat.
A higher angle of attack which is likely to achieve more lift would likely to yield better performance.

Tuesday, March 3, 2015

1 - Aerodynamic Group Meeting on 3rd March, Reflection and Plans


the first wooden model that we tried to build.


There was a lot of on-site decision to be made because certain things had been overlooked. This is sth we can improve in the future.
So can this WIG model fly like John Schuster's one?
Sadly, no.
Why?

1) Wing area is too small.
First comment made by Prof Kim on seeing the model was that the wing is too small.
Well, we didn't do any calculations and was just trying to come up with a simple design based on the one that's in the optimal WIG paper.
Secondly, limited by material. Didn't have sufficient material.....so now we know that roughly 4 pieces of wood with dimension 300mmx200mm would be good for one model.
2) Too heavy.
The use of plywood is likely to be the root cause.
Again, calculation, weight and lift need to balance each other.


So what's good?
1) Endplates.
The endplates act as point of contact with the ground, and as the surface of contact with the ground is very small which means little drag, which is good.
2) A lifting tail. Perhaps, a better quality one can be made and the tail needs to be more stable.

Skills to be carried on to future models.
1) Hands-on experience.
Laser cutting skills. Dealing with simple tools and the need to improvise on the spot.
2) Process.
i. State the purpose e.g what's to be achieved from the model
ii. Design brainstorming
iii. Plan on how to construct and join different parts together
iV. CAD and simple analysis
v. Material selection and purchase
vi. Final preparation for building the model and PowerPoint slide for presentation
vii. Building
viii. Testing
iX. Review/Reflection/Conclusion

(by Stanley)