optimax dynamic, llc dr. james c. huan optimax dynamic, llc august, 2014
TRANSCRIPT
![Page 1: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/1.jpg)
OptiMax Dynamic, LLC
MARINE IMPULSE THRUSTER (MIT) from
EFFICIENCY, LINEARITY and EFFECTIVENESS POINT OF VIEW
Dr. James C. Huan
OptiMax Dynamic, LLC
August , 2014
![Page 2: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/2.jpg)
OptiMax Dynamic, LLC
Overview Why Impulsive or Unsteady Propulsion?
Marine animals chose it over millions of years of natural selection;
Theory and laboratory tests proved its superiorities; Athletes manually use it in boat racing.
Why Not Impulsive Propulsion for All Marine Vehicles? Man-made device to achieve a simple and efficient cycle for
Impulsive Propulsion for marine vehicles is the challenge!
Patented Side-Intake Concept for MIT Overcame the Challenge! Working principle of the Side-Intake MIT; MIT examined from Efficiency, Linearity and Effectiveness perspectives; Development plan for MIT.
A View for the Future
![Page 3: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/3.jpg)
OptiMax Dynamic, LLC
Why Impulsive or Unsteady Propulsion? Marine animals Chose it Over Millions of Years of Natural Selection
Caudal Fin
A fundamental feature of Impulsive Propulsion is the impulsive jet flow characterized by well-structured large thrust vortices such as vortex rings. Fish impulsively sweep its caudal fin to generate a wavy impulsive jet (see Fig.-1); DPIV revealed chain-connected inclined vortex rings in the jet flow from fish.
Squid contracts body muscle to generate impulsive jet through its siphon; Squid is able to generate perfect vortex rings.
https://www.youtube.com/watch?v=bK5IdL23AMs
For the size of a giantsquid and how quick it acts forits prey, watch TV news clip at:
reverse Karman street
a perfect vortex ring
Fig.-1
chain-connected inclined vortex rings
reverse Karman vortex street
![Page 4: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/4.jpg)
OptiMax Dynamic, LLC
Why Impulsive or Unsteady Propulsion? First-order Theoretical Analysis
Energy losses in steady propulsion devices (propellers or impeller-driven pump jets):
• viscous shear loss (vorticity instability and turbulence)
• cavitation loss• slip losses including axial and tangential
steady propulsion jet flow(unstable vortices turn into turbulence)
impulsive propulsion jet flow
from Jojn Dabiri, CalTech)( infxjet, VVQT )2
1
2
1( 2
inf
2
jet VVQWin
xin
useful
VV
V
VVQ
TV
W
W
jet,inf
inf
2
inf
2
jet
inf 2
)(2/1
Vinf
Vjet
T
Jet or Ideal Efficiency!
Impulsive Jet from piston-cylinder setup: • minimum loss from vorticity instability and turbulence;
• axial slip loss only, meaning achieving ideal efficiency. a perfect jet model(only axial flow velocity !)
![Page 5: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/5.jpg)
OptiMax Dynamic, LLC
Why Impulsive or Unsteady Propulsion? Findings from Experimental Studies on Impulsive Jet Flow
“A Universal Time Scale for Vortex Ring Formation”by Gharib, M.,et al., JFM, (1998).
Piston-cylinder setup is ideal for optimum Vortex Ring generation resulting in a momentum augmentation in jet flow through: • ambient mass entrenchment into the Vortex Ring; • over-pressure at jet exit to accelerate the Vortex Ring (Gharib, JFM, 1998).
Impulsive Jet could increase propulsive efficiency up to 50% over the steady jet (Ruiz, Whittlesey & Dabiri, JFM, 2011).
from Jojn Dabiri, CalTech
VRT Krieg & Mohseni,(J of Oceanic Eng.,2008)
a VRT model
vortex ring frompiston-cylinder setup
![Page 6: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/6.jpg)
OptiMax Dynamic, LLC
Athletes Manually Use Impulsive Propulsion in Boat Racing
Why Impulsive or Unsteady Propulsion?
moving direction
a practical example of reverse Karman street !
Oar cycle achieves efficient impulsive propulsion, but manually: • impulsively expel water to maximize the reverse Karman vortex for thrust; • recover oar through air for minimum energy waste; Analysis shows using piston-cylinder setup to expel water will be more efficient than oars (see analysis):
γV sin
γVωR sinωR
ω
Slip velocity: sinVRuu ns Power loss on blade: )sin( VRNEblade
Power Input: RNEinput
Propulsive efficiency:R
V
E
EE
input
bladeinput
sin
Assume: (1) force, ‘N’, in blade normal dir.; (2) no friction.
aR
VI
1
1
ideal efficiency only at !
an oar analysis model2/
![Page 7: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/7.jpg)
OptiMax Dynamic, LLC
Why not Impulsive Propulsion for All Marine Vehicles ?
Take a break here if you want !
Give a Summary:
Impulsive Propulsion is proved to be superior over Steady Propulsion.
Piston-cylinder setup is ideal for Impulsive Propulsion.
Then, why not Impulsive Propulsion? Man-made device to achieve a simple and efficient cycle for Impulsive Propulsion for all marine vehicles is the challenge !
Patented Side-Intake concept for MIT for the first time overcame the challenge !
![Page 8: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/8.jpg)
OptiMax Dynamic, LLC
Working Principle of the Side-Intake MIT System open intake holes near discharging end. require a valve to open and close
intake holes. separate cylinder with a dry and a wet
compartment during piston motion. achieve oar-like cycle, but under water. need two cylinders for continuing water
flow from inlet to jet exit.
Patented Side-Intake Concept for MIT
jjoopp VAVAVAQ
)( ij VVQT )2
1
2
1( 22
ajp UVQW 22
222
aj
ij
ij
a
p
usefulpropulsor UV
VV
VV
U
W
W
Intake process
Discharge processContinuous flow during a cycle
valve opened
valve closed
![Page 9: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/9.jpg)
OptiMax Dynamic, LLC
Side-Intake MIT Actual Configuration
(1) jet nozzle;(2) 4 cylinders;(3) 4 inner ring rotational valves;(4) ball bearings;(5) permanent magnets;(6) 4 electrical coil winding pats; (7) 4 pistons;(8) 4 absorbing springs, one for each piston;(9) baffle cap.
MIT is similar to Axial Piston Pump,but for flow rate and momentum producing.
Patented Side-Intake Concept for MIT
![Page 10: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/10.jpg)
OptiMax Dynamic, LLC
MIT examined from Efficiency, Linearity and Effectiveness perspectives
Patented Side-Intake Concept for MIT
MIT can have a more than 30% efficiency increase over the best marine propulsor in use today
control volume for MIT control volume for propeller
• PD efficiency is nearly a constant;• PD efficiency is much higher than ND;• ND efficiency is a nonlinear ‘‘bell curve’’.
flow all in axial direction ! having swirl loss !
ω
Propulsor to Power Input
ThrustV
Propulsor to Power Input
Power Thrust ship overall
mpumpflowjetoverall
ideal
jiij
ijet AAVV
V
/1
22
requiredenergy kinetic flow
ThrustVship
loss) swirl (e.g. fluid to addedenergy kinetic total
requiredenergy kinetic flow flow
fluid on done workmechanical
fluid to adddenergy kinetic totalpump efficiency electrical
and mechanical : m
For MIT: 1flow
const a and %90pump
idealjetoverallMIT
(even without considering momentum augmentation from Vortex Ring)
1m
![Page 11: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/11.jpg)
OptiMax Dynamic, LLC
MIT examined from Efficiency, Linearity and Effectiveness perspectives (cont’d)
Patented Side-Intake Concept for MIT
MIT is a linear performer, which is extremely important for vehicle’s acceleration and maneuverability !
pump• because MIT is a PD pump and its is nearly a constant regardless of changes to a vehicle’s load condition (e.g. during acceleration or maneuvering).
MIT is more effective than the most effective pump jet ever designed
• Effectiveness of a power machine is a power density question.• For a propulsor, ideally to have the most compact system to generate a given thrust power without sacrificing its efficiency.
)( infxjet, VVQT Let’s look at the thrust equation:
• To Increase for larger T leads to larger slip loss and so sacrifices efficiency, not good !• Ideally, it is to increase flow rate, , for larger T.• However, is proportional to a propulsor’s size. • The effectiveness question is to answer: among the same size of propulsors, which propulsor can produce the most flow rate, ?
)( infxjet, VV
QLet’s do an analysis!
![Page 12: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/12.jpg)
OptiMax Dynamic, LLC
Patented Side-Intake Concept for MIT MIT is more effective than the most effective pump jet ever designed (cont’d)
• The capacity coefficient,
3/nDQCQ where: n is RPM, D is the diameter of the propulsor
determines the effectiveness or compactness of a propulsor !• For the same diameter and RPM, the larger, CQ , the more effective or compact.• Axial-flow pump jet is the most compact propulsor in use !• For Axial-flow pump, CQ is not a const. because Q and n is in a very nonlinear relation. • The highest CQ ever found is in
ONR AxWJ-2 Pump Jet, CQ, ONR =0.85 !
MIT cylinder d and system D
A typical axial-flow pump curve. The best efficiencyCQ is around 0.55
• For MIT, CQ is a constant and equals to
ratio) diameter to (stroke whereMIT Q, dLndQC // 3
)21/( DdPump Jet D and MIT d relation:
071.0/ 3nDQC MIT Q,
126.0 ONR Q,
MIT Q,
C
CFor i.e. just make 8.3 MIT can be more effective !
Besides, because CQ, MIT is const., we can always increase n for large Q !
Using D instead of d:
![Page 13: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/13.jpg)
OptiMax Dynamic, LLC
Development plan for MIT
Patented Side-Intake Concept for MIT
(This slide is purposely blanked !Interested readers can obtain the information throughdirect contacting us.)
![Page 14: OptiMax Dynamic, LLC Dr. James C. Huan OptiMax Dynamic, LLC August, 2014](https://reader036.vdocuments.site/reader036/viewer/2022062300/56649c915503460f9494c67d/html5/thumbnails/14.jpg)
OptiMax Dynamic, LLC
A View for the Future
MIT is a disruptive technology in maritime industry.
As a jet engine is the heart for an airplane, MIT is the heart for a marine vehicle.
MIT powered by advanced electric drive will bring about a new revolution in the industries of shipbuilding and maritime transportation.
Q & A