Greetings from south Texas. After lurking for about a year, I have
decided it was time officially join.
My technical background is in mechanical engineering with a bent towards
fluid mechanics. I have spent the last 20 years of my life in various research
capacities in the oil and gas business and in academia. I retired about a year and a half ago
and now am able to focus on a dream I have had since I was a kid, which is to
build a personal submersible. I have spent many profitable hours digesting the
content in the archives and using the search features. Many thanks to those of
you that have contributed over the years.
I have spent the last year designing a two-manned, 1 atm. dry submersible rated to 300 fsw. I would estimate that I am about
90% through the detail engineering phase of the project.
I am
designing to ABS rules but due to the cost for ABS certification, I am not
planning on certifying the boat. I am using Autodesk Mechanical Desktop for part
design, documentation, and 3-D weight and buoyancy orientation. I am using Excel
for a CG and CB calculations as well as for the material takeoff. The sub is
quite a bit smaller than Carsten Standfuss CSSX but larger than his Sgt.
Peppers. Come to think of it, I guess this is true for all Psubs! I have designated my sub the R300. It has an overall length of 18 ft and a
width, pod to pod of 6.6 ft, a height of 5.6 ft, and a draft of 2.8 ft. FRP is used for the hydrodynamic shell
for both the pressure hull and the two external battery pods. The pressure hull
is ASTM A516 Grade 70, with a diameter of 3 ft. The hull thickness is 0.25 inch
with internal stiffening frames.
The surfaced and submerged displacements are 5,264 lbs and 5,859 lbs
respectively with an ROB of 12%.
Payload capacity is 350 lbs with 433 lbs of drop weight. Normal dive time is 7 hrs with reserve
capacity of 72 hours via two externally mounted O2 bottles. There are a total of
seven acrylic view ports, one 24-inch hemispherical port, two 20-inch
cylindrical view ports and four 10-inch diameter cylindrical view ports all
designed to ASME PVHO-1-1997 standards.
There are two external soft MBTs located fore and aft as well as two
internal soft VBT’s again located fore and aft. MBT’s are blown by air from four scuba
tanks, regulated down to 225 psig.
The VBT’s are filled/emptied using a PD pump driven off a hydraulic
motor. Longitudinal trim is
achieved by hydraulically articulating battery boxes in the external pods. There is a dual propulsion system
that utilizes a jet ski pump. The jet ski nozzle is used for pitch and yaw
control while wing mounted ailerons are used for roll control. Submerged power is directed to a 19 HP,
DC series wound motor, connected to ten 12 VDC deep draft marine batteries. The
motor is controlled with a MOSFET DC motor controller. Surface power comes from
a 110 HP two-stroke Rotax engine with intake and exhaust piping vented on
opposite sides of the sail. If
there is any interest, I could post a Mechanical Desktop rendering to the
discussion group.
Are
there any Psub enthusiast in Texas?
I am nearing the stage where I need to do a detailed design review before
I start part procurement and fabrication.
I was delighted to see the intent of the organization to host it’s first annual convention in Portland. My wife and I are planning on attending. Where better to celebrate our 27th wedding anniversary.