STATEMENT OF WORK.pdf

Scott Hromisin scott.m.hromisin.civ@us.navy.mil AB21600

Item 1: Static Pipe Specifications I. The proposed pipe shall be designed for installation through the test section of the Naval

Aerodynamic Test Facility (NATF) wind tunnel (WT) in room 1B45 of Building 2187, Patuxent River, MD. The NATF test section is 4 feet high x 4 feet wide x 8 feet long. A photograph of the NATF WT, and coordinate system, are shown in Figure 1.

II. Static Pipe Design and Fabrication

a. The proposed pipe shall consist of two major sections: 1) an ogive-shaped nose, followed by 2) a constant outer-diameter downstream section (COD section).

b. Ogive Nose

i. The ogive-shaped nose will be axisymmetric, and 8 inches in length, with a maximum OD of 3 inches. The outer mold line (OML) of the nose has been provided by the NAWCAD.

1. The radius, R, of the OML, is defined a function of axial position, X, using the following equation (with all units being in inches), 𝑅 = 𝑅 − 𝑥 − 𝑅 , 𝑥 ≤ 0.0549

0.00315𝑥 − 10.0746𝑥 + 10.6631𝑥 . + 0.0653, 𝑥 > 0.0549 where 𝑅 = 3/16in.

2. A two-dimensional cross-section contour of the ogive nose OML is shown in Figure 2

3. A discrete list of points, in both Cartesian and Cylindrical Polar coordinates, is given in Table 1.

ii. A SolidWorks CAD file on the ogive noise OML can be provided upon request.

iii. The nose shall have the ability to be detached from the COD section.

iv. The nose shall be fabricated from stainless steel, and be hollow.

c. COD Section

i. The COD section described in this section: Item 1, Section II.c, without any pressure taps, shall be considered the “blank” COD section.

ii. The COD section described in this section: Item 1, Section II.c, with all pressure taps drilled, tap plumbing installed, flats machined on the aft end of the section, and connections for pipe suspension machined in, shall be considered the “complete” COD section.

iii. The COD section shall have an outer diameter of 3 inches and be hollow.

iv. The COD section shall be fabricated from drawn aluminum.

v. The inner diameter (ID) of the COD section shall be large enough to contain all pressure tap tubing as well as the electronically scanned pressure (ESP) module, including all wiring and tubing for the module.

vi. The ESP module will be mounted in the COD section by NAWCAD.

1. The location of the ESP module mounting position within the COD shall be at a location most convenient for eventual assembly.

2. The static pipe shall be designed to allow the ESP module to be removed from the pipe.

3. The cable for the ESP module is 30 feet in length, and shall be able to exit the pipe and NATF WT test section, and connect to the data acquisition system next to the WT, without disrupting pressure measurements or needing an extension cord.

vii. A dimensioned engineering drawing the ESP module is shown in Figure 3.

viii. The COD section shall be 216 inches in total length, and be constructed from a single segment of pipe. A conceptual diagram of the NATF WT, with static pipe installed, is shown in Figure 4.

ix. Three (minimum) or four (maximum), 1.00 inch square flat sections (flats) shall be machined into the exterior surface of the COD section.

1. A diagram of the static pipe with four flats is shown in Figure 5.

2. The flats shall be machined into the aft end of the COD section, with the start of the flats 223 inches from the tip of the ogive nose.

3. The flats shall be separated by 90 degrees, with the first flat at 90 degrees, with respect to top-dead center.

d. Fabrication

i. The final, complete design of the static pipe design shall be one that the CONTRACTOR can completely fabricate in their machine shop with their shop’s current capabilities.

ii. As part of the competed design, the CONTRACTOR shall provide the recommended torque for any screws and fasteners.

iii. All surfaces, curves, joints, etc. shall be smooth and blended to their mating surfaces. All the material should be non-corrosive. Use of non-hardening putty, body contouring, and filling may be permitted to cover fasteners or joints if prior permission is granted by NAWCAD.

iv. All fasteners shall be non-corrosive. When threads are required in non-ferrous metals, steel threaded inserts (self-locking or equivalent) shall be used. All fasteners shall be flush or recessed with respect to the OML.

v. The nose and COD section shall be manufactured using multi-axis, computer numerically controlled (CNC) milling machines, CNC lathes, wire electronic discharge machines (EDM), and conventional mills and lathes, as deemed appropriate by the CONTRACTOR.

III. Strength and Tolerances

a. The OML dimensional tolerance on the ogive nose and COD section shall be

±0.005 inches. A maximum mismatch of 0.001 inches on mating and alternative assemblies shall be allowed. When assembled, no joint gaps shall exceed 0.001 inches. Forward facing steps shall not exceed 0.001 inches. Aft-facing steps shall be limited to a maximum of 0.001 inches.

b. The design of the fully-assembled pipe shall be rigid enough to not have a centerline deflection angle exceeding ±0.16 degrees, nor shall the centerline displacement (i.e. pipe sag/droop) exceed 0.30 inches, at any point along the length of the pipe.

IV. Pressure Tap Specifications

a. All pressure taps shall have a diameter 0.02 inches.

b. The pressure taps shall be drilled perpendicular to the surface, and will be freed of all burrs and any other fouling that may result from machining processes.

c. Pressure taps will be drilled at seventeen axial stations (distance along pipe as measured from the nose), with four pressure taps per axial station, for a total of sixty-eight taps. These taps will be referred to as the seventeen GroupsOf4. Three views of the static pressure tap layout are shown in Figure 6.

i. Each of the seventeen GroupsOf4 are shown in Figure 6 as the blue, red, or yellow tee’d groupings, with each tap location marked with an asterisk.

ii. Each tap in each GroupOf4 shall be azimuthally separated by 90 degrees.

That is, at each axial station, the four taps will be equally spaced around the circumference of the pipe.

iii. Each GroupOf4 will be plumbed together (tee’d together) so a single pressure line shall each group to the ESP module.

1. Each GroupOf4 may be tee’d together at a location most convenient for assembly.

2. The CONTRACTOR shall connect all tubing prior to delivery to the NATF WT.

3. Flexible plastic or rubber tubing will connect the pressure taps to the ESP module, and the flexible tubing shall have an inner diameter of 1/16 inch. NAWCAD will be responsible for connecting the tubing to the ESP module.

d. Pressure taps will be drilled at six axial stations (distance along pipe as measured from the nose), one tap per axial station, at an angle of 90 degrees, as measured from top-dead center (+Z axis) of the pipe.

i. Tap locations are marked in Figure 6 with black crosses.

ii. The first tap shall be drilled 80 inches downstream from the tip of the ogive nose. Each of the five subsequent taps shall be separated by 19.2 inches.

iii. A single tube will run from each tap to the ESP module.

iv. The CONTRACTOR shall connect all pressure tap tubing prior to delivery to the NATF WT.

v. Flexible plastic or rubber tubing will connect the pressure taps to the ESP module, and the flexible tubing shall have an inner diameter of 1/16 inch.

The NAWCAD will be responsible for connecting tubing to the ESP module.

e. Pressure taps will be drilled at six axial stations (distance along pipe as measured from the nose), one tap per axial station, at an angle of 270 degrees, as measured from top-dead center of the pipe.

i. Tap locations are marked in Figure 6 with black crosses.

ii. The first tap shall be drilled 80 inches downstream from the tip of the ogive nose. Each of the five subsequent taps shall be separated by 19.2 inches.

iii. A single tube will run from each tap to the ESP module.

iv. The CONTRACTOR shall connect all tubing prior to delivery to the

NATF WT.

v. Flexible plastic or rubber tubing will connect the pressure taps to the ESP module, and the flexible tubing shall have an inner diameter of 1/16 inch.

The NAWCAD will be responsible for connecting the tubing to the ESP module.

f. There shall be a means to access and repair/replace all tubing in the event of damage or fouling.

g. NAWCAD has provided the center positions of all pressure taps as a table of X,Y,Z (Cartesian), and X, R, φ (cylindrical polar) coordinates in Table 2.

Item 2: Static Pipe Suspension, Support, and Installation I. The static pipe shall be suspended in the NATF WT using eight cables.

a. The cables shall allow the longitudinal axis of the static pipe to be positioned within 1/16 inch of the test section centerline.

b. The cables shall be adjustable to be able to position the static pipe at other locations within the WT test section.

c. The diameter of the cables, including coating, shall not exceed ¼ inch.

d. The CONTRACTOR shall provide a minimum of ten cables.

e. Four of the cables shall connect to the pipe within the first 14 inches of the pipe, as measured from the tip of the ogive nose. The cable connections shall be azimuthally spaced 90 degrees apart, with the first cable connection at 45 degrees, as measured from top-dead center (+Z axis) of the pipe (i.e. cables will make an X pattern when viewed head-on).

f. Four of the cables shall connect to the pipe within the last 12 inches of the pipe, as measured from the trailing edge. The cable connections shall be azimuthally spaced 90 degrees apart, with the first cable connection at 45 degrees, as measured from top-dead center (+Z axis) of the pipe (i.e. cables will make an X pattern when viewed head-on).

g. The cable connections to the pipe shall be of a low-profile design that minimizes airflow disturbances around the pipe. The cables may connect internal or external to the pipe, or may have offset connections (e.g. eye bolts).

h. Each cables shall have a means of setting the tension up to 200 lbs. All connections and hardware, including the WT walls (if applicable), must be able to withstand this loading without any appreciable risk of deformation or failure.

i. The cables may connect to either the interior or exterior of the NATF WT.

i. The location of all holes shall be specified by NAWCAD. It should be anticipated that the cables to be angled approximately 40 degrees with respect to horizontal (see Figure 4).

ii. Connections shall be removable from the WT.

iii. The cables shall be detachable from the connectors.

iv. The walls of the NATF WT consist of approx. 1/8 inch sheet metal with external angle iron structural ribs (see Figure 1).

v. NAWCAD shall be responsible for drilling all holes and installing the cable connections.

j. Approximate locations for two of the forward and aft cable connections, to both the static pipe and NATF WT, are shown by the red lines in Figure 4.

Item 3: Pipe Transport, Delivery, and Storage I. The NAWCAD shall be responsible for delivering the static pipe and all associated hardware of this contract to the NATF WT in room 1B45 of Building 2187, Patuxent River, MD.

II. The NAWCAD shall be responsible for the design and fabrication, and/or acquisition of crates and any other containers/hardware necessary to transport the static pipe “blank” COD section, ogive nose, supports, and all other hardware.

Item 4: Contract Deliverables The CONTRACTOR shall deliver the following upon the completion of this contract:

I. All completely manufactured hardware described in Item 1 and Item 2, including all connectors and suspension cables, ogive nose, and COD section, fabricated according to the designs proved by Advanced Technologies, Inc.

II. The “complete” COD Section, manufactured to adhere to all details described in Item 1, including pressure taps, all the associated hardware/piping, installed on/within the COD section (Item 1, Section IV), fabricated according to the designs proved by Advanced Technologies, Inc.

III. System Cost

a. Please include an itemized, estimated cost breakdown for the fabrication of the remainder of the static pipe system as detailed in this document.

Figure 1. NATF WT with test section dimensions and coordinate system, with origin located at the tunnel centerline

Figure 2. Outer mold line for the ogive nose. Nose radius is 0.1875in.

Table 1: Discretized points for the outer mold line of the ogive nose in Cartesian and Cylindrical Polar coordinate systems

Coord Sys:

# X(in) Y(in) Z(in) X(in) Phi(deg) R(in) 1 8 0 -1.5 8 0 1.5 2 7.96027 0 -1.49999 7.96027 0 1.49999 3 7.92055 0 -1.49994 7.92055 0 1.49994 4 7.88082 0 -1.49987 7.88082 0 1.49987 5 7.8411 0 -1.49976 7.8411 0 1.49976 6 7.80137 0 -1.49963 7.80137 0 1.49963 7 7.76165 0 -1.49946 7.76165 0 1.49946 8 7.72192 0 -1.49926 7.72192 0 1.49926

Cartestian Cylindrical Polar

Figure 3. Engineering drawing of ESP module for static pipe. All dimensions given in inches, unless otherwise noted

Figure 4. Conceptual diagram of NATF WT with static pipe installed.

Figure 5. Diagram of four 1 inch square flats machined into the aft end of the COD section of the static pipe

Figure 6a. Head-on view of the static pressure tap layout looking in the downstream direction

Figure 6b. Side view of the static pressure tap layout

Figure 6c. Isometric view of the static pressure tap layout

Figure 6. Static pressure tap layout

Table 2. Pressure tap locations in Cartesian and Cylindrical Polar Coordinates. GroupsOf4 have the same Station #, and the six independent taps on the left (L) and right (R) side of the pipe have Station #’s IL1-6, and IR1-6, respectively.

Coord Sys:

Station # X (in) Y (in) Z (in) R (in) Phi (deg) X (in)

1 56 0.00000 1.50000 1.5 0.000 56 1 56 1.50000 0.00000 1.5 90.000 56 1 56 0.00000 -1.50000 1.5 180.000 56 1 56 -1.50000 0.00000 1.5 270.000 56 2 68 -0.14703 1.49278 1.5 -5.625 68 2 68 1.49278 0.14703 1.5 84.375 68 2 68 0.14703 -1.49278 1.5 174.375 68 2 68 -1.49278 -0.14703 1.5 264.375 68 3 80 -0.29264 1.47118 1.5 -11.250 80 3 80 1.47118 0.29264 1.5 78.750 80 3 80 0.29264 -1.47118 1.5 168.750 80 3 80 -1.47118 -0.29264 1.5 258.750 80

Cartesian Cylindrical Polar