|
JETCRAFT. Водомёт. Водомётный движитель. Теория. Лодка. На что обратить внимание. Руководство пользователя. (Boats: What to Look For . Buyer guide) |
Marathon Marine - web. Cтатья очень доходчиво рассказывает НА ЧТО ОБРАТИТЬ ВНИМАНИЕ при покупке лодки или водомётного катера.
|
NEW. Росомаха (img) русский конкурент Harbercraf / Jetcraft
Byuer Guide Руководство покупателя
Фотографии с выставки "MIBS 2009" Закон и катер. Постановка на учёт катера со стационарным двигателем. дюймы в сантиметры
Форумы на тему... с переводом.
Harbercraft 1875 J-Max White Water (img)
2075 White Water (img)
1875 J-Max XS (img)
2175 XS Фотографии с выставки "Охота и рыбалка - 2008"
Marathon Marine and Northwest Jet Boats (link)
PHANTOM Jet Boats (link)
RiverPro®. (link)
North Silver PRO 675Jet lnk
Росомаха (img)
Tom 525. Томь 525.
Коллекция ссылок на тему: водомёты для судов (Links). Курс доллара
Друзъя
|
Radius Bottom Круглое дно. Regardless of past experience or current preferences, both V type hulls are lacking when
compared to the Radius Bottom. Beginning with the bow entry, Marathon’s modified
shallow bow entry produces an all around smooth ride in rough water yet superb buoyant
lift in white water conditions. The ride is unlike anything most operators have
experienced. The Radius Hull really shines when the boat is driven hard and fast. When
test driving this hull we have noticed experienced operators instinctively bracing
themselves when setting up for and initiating a hard turn. They are pleasantly surprised
by the solid “no surprises” performance of this hard turning hull type.This solid sensation
is generated by the Radius Hull. The following explains why this works.
There are two lifting forces that come into play on a planing hull: Hydrostatic and
Hydrodynamic.
The lift force acting on a stationary (static) hull is known as Hydrostatic.
Lift forces from moving water (under the hull) are known as Hydrodynamic.
A planing hull gets most of its lift from Hydrodynamic forces. Although Hydrostatic
force provides some lift, the bulk of it is provided by the Hydrodynamic force.
Hydrostatic and Hydrodynamic force is always applied at right angles to an object - in
this case the full surfaces.
The radius of the Marathon keel found on all Spirit models runs the full length of the
bottom and spans 28”. Think of the radius portion of the bottom like a half pipe or barrel
on the bottom.
Under ideal water conditions, the hydrodynamic forces on the bottom, either a radius or
V bottom boat, are directed at right angles to the exposed surface. This means that in
straight ahead motion, this force is directed to the center of the hull for both the radius
and V hulls. The difference is found during times when the water conditions are not ideal
- which in the real world is most of the time!
When the boat turns, the water pressure on the side of the hull exposed to the inside of
the turn increases. As the boat turns, on a V bottom boat the water pressure pushes/tilts
the boat slightly. Why is this? The water pressure is constant along the hull on the inside
of the turn but then suddenly stops at the bottom of the V. Therefore, like porpoising one
can get a rocking or falling off on a plane. |
Boats: What to Look For. НА ЧТО ОБРАТИТЬ ВНИМАНИЕ при покупке лодки. Введение Сварные лодки в общем Наши предпочтения
Buying a Welded Boat for the First Time
Bottom Width and Engine Size and Type.
Stability at Speed: Porpoising versus bow down Дельфинирование.
Boat Materials: Aluminum versus Fiberglass .
Cost differences between glass and aluminum . Сравнение стоимости стекловолокна и алюминия. Types of Aluminum. Типы алюминия.
Material Thickness
A Word about Welding
Suck marks, caterpillar tracks
Folded, ‘Origami’ Construction
Deadrise (Vee)
Planing Hull Bottom Types Корпус с дном плоского типа
Constant deadrise V (including modified V hulls)
Flat bottom hulls (8 degrees deadrise or less)
Bow Entry Types. Тип носа катера
Radius Bottom Круглое дно.
Lateral Stability During Planing Turns
Bottom Shape and Jet Intake
Planing Ability
Reverse Chines
Bottom Width: Flair is not everything
No Trim.
Hull Construction Standards
Shallow Water Operation
No Exposed Drive
Safety
Thrust line and Center of Gravity In line
Propeller Torque is Different than Impeller Torque
Propulsion Resistance.
Power Plants Силовая установка. Derived from Impeller Curves.
RPM Curve Derivation
Conclusion
Hull Resistance. Boat attitude..
Jet Drives
How jets work .
Impeller
Cut.
Cut, Speed and Load
Wear ring.
Nozzle
Stator.
Hard Anodized.
Cavitation .
Intake
Seals
Mixed flow
Axial flow.
Outboard jet:
Inboard jets:
So, what is the best jet?
Corrosion.....
UHMW...
Jet Diagnosis...
Rattle at Idle (V8 boats)
Speed too low for a Given RPM.
Poor acceleration or ‘holeshot’, combined with high top end
Definitions.
Porpoising .
Chine walk: 9
Ram effect .
Static thrust:
|
Водомётный движитель. ТЕОРИЯ.
Адрес для переписки:
Spiridonov S. E.
|
JETCRAFT. Водомёт. Водомётный движитель. Теория. Лодка. На что обратить внимание. Руководство пользователя. (Boats: What to Look For . Buyer guide) |