SATPC0035883 Tab 04 SOW_Redacted.pdf

Statement of Work

BACKGROUND

Particle Image velocimetry (PIV) technique is the state of the art non-intrusive, optical technique to provide instantaneous snapshots of velocity field within a three-dimensional volume in space. There are several levels of PIV. 2-D PIV, which uses one camera, measures 2-components of velocity in a plane. Stereo- PIV uses two cameras and measured 3-components of velocity in a plant. The highest level is the 3-D tomography PIV that uses 4 or more cameras and measures 3-components of velocity in a volume.

One of the fundamental issues with using tomographic PIV is the influence of “ghost particles”, which refers to potential, but unreal, solutions to that identifying smoke particles present in the flow. The presence of ghost-particles leads to incorrect values in measurements making them unusable. There are two ways to solve the problem: (1) ensure that the seeding is less than a threshold value (0.1 particles per pixel) or (2) add additional cameras to accurately resolve the location of the particle. Currently, Army has 4 cameras for conducting tomographic PIV.

The present proposal is to upgrade all the four cameras for increased light sensitivity and improved spatial resolution that improves the quality of tomographic PIV images.

As mentioned earlier, Tomo-PIV measures velocities over a volume. The lasers that are used, however powerful, are often insufficient to produce enough intensity that increases S/N ratio when the volume is reasonably big (as in the case of many rotor experiments conducted at the Army hover facility). To compensate this, the cameras can be made more sensitive to the light. Instead of CCD sensors, the proposed procurement is for cameras with backlit cMos sensors that are more sensitive to light. Higher sensitive cmos sensors compensate for the reduced intensity light that is distributed over a large volume.

The following list of relevant equipment is held at the Army inventory.

1. LaVision Davis 10 operating license

2. LaVision PTU x synchronizer

3. 4 units of Imager Pro LX

4. Seeders of different sizes (0.25, 0.9, and 20 micrometers)

Following is the list of items to be purchased:

1. 2 units of Imager CX3p25

2. 2 units of Imager CX3 25 is the end user of this system, and he works at the U S. Army Aeroflightdynamics directorate located at the NASA Ames Research

Center in Moffett Field, CA. As the system must be used by a laser authorized user, will be using the PIV system.

The PIV system will be used in many projects, beginning from validating numerical observations made by high fidelity computational codes in terms of identifying physical features in the rotor flow field, as well provide accurate measurements towards understanding the relationship between rotor wake and its performance.

OBJECTIVE

To upgrade 4 existing 16MP LaVision cameras for higher spatial resolution and increased light sensitivity towards increasing s/n ratio of the images. Higher quality images directly translate into improved quality data.

PLACE OF PERFORMANCE

The following should list the location or department where the item/items or work will be done:

LaVision facility at Minneapolis, MN

PERIOD OF PERFORMANCE

When the work will begin and when the work will be completed.

September 30, 2024.