Attachment A - SOW - Turbine Air Motors.pdf

Wind Tunnel Propfan Turbine Air Motor (TAM) Specifications for Full Model Powered Testing in the NASA Ames 11x11 Foot Unitary

Plan Wind Tunnel

This procurement is for four (4) turbine air motors (TAMs) for upcoming propulsion-airframe integration (PAI) testing in the Ames Research Center 11 Foot Unitary Plan Wind Tunnel (UPWT).

There will be two primary TAMs and two backup units. The TAMs will be integrated with an airframe body/wing model in the UPWT to test aerodynamic performance at high-speed/cruise conditions. The requirements for these units has been determined with our industry test partners and will be used to procure tailored commercial off the shelf (COTS) TAMs from a qualified vendor.

General Requirements and Objectives:

Because of the high expense and flow time required to design and/or fabricate new powered propulsion simulator motor hardware, the primary rationale for the simulator motor requirements listed below is to make any such hardware acquired as flexible as possible or practical. Other rationale items are listed with each specific requirement or objective.

• TAMs shall be capable of testing isolated and installed Proposed and foreseeable thrust/drag bookkeeping procedures for exposed propulsor engines will require isolated and installed wind tunnel testing.

• TAMs shall be capable of testing upright and inverted Related to the various types of mounting systems which might be employed for isolated and installed testing.

• TAMs shall be capable of testing in multiple facilities While the initial intent is to use the propulsor simulator motors in the Ames 11x11 foot Unitary Plan Wind Tunnel, the simulator motors should be capable of testing at any wind tunnel facility which features the proper simulator motor power source (electric, pneumatic, hydraulic).

• TAMs shall be as compact as possible (i.e., state-of-the-art power density) Full model airframe testing typically requires the propulsion simulation to be as compact as possible. State-of-the-art designs will feature the most compact physical packaging (i.e., highest practical power density).

• TAMs shall be reversible (i.e., capable of simulating tractor and pusher engines) While the current focus is on tractor propulsors mounted on the wing, pusher propulsors mounted on the wing or on the aft body are also possibilities.

• TAMs shall be capable of simulating either single or contra-rotating fans Other propfan engine concepts, such as contra-rotating propulsors, are also valid, so both concepts must be accommodated by the same powered propulsion simulator motor hardware.

• TAMs shall be capable of locked operation (to simulate feathered blades) The size of modern exposed propulsors indicates that a failed engine in the windmilling mode is not practical. Therefore, the propulsor blades will likely be feathered when the engine fails (i.e., experiences an in-flight shutdown or a fan blade out event). In such a scenario, the feathered blades may be rotating slowly or may be locked in place, depending upon failure mode and/or engine company control philosophy.

• TAMs shall be available in handed configurations (i.e., versions with front rotors turning clockwise and counter-clockwise) Current BCA Product Development safety philosophy for exposed propulsor engines, as well as practical wing design considerations, dictate that the rotors on opposite wings rotate in opposite directions (i.e., counter-rotating propulsors). Therefore, full span wind tunnel models must also be configured in that manner. Either handed configuration (clockwise or counter-clockwise) must be mountable on either side of a full model.

• TAMs shall be sufficiently reliable For exposed propulsors, the majority (possibly all) wind tunnel tests will be powered, requiring a fundamentally different level of reliability for the powered propulsion simulator hardware. Currently, high and low speed full model tests may involve several months of occupancy with air on at least half the time.

• TAMs shall be acquired in sufficient numbers to ensure spares for continued testing Powered propulsion wind tunnel simulators have generally been shown to be somewhat unreliable. Sufficient spares must be available to allow continued testing for complicated and lengthy tests (i.e., at least 4 copies for handed configurations – 2 CW and 2 CCW – for full model testing).

• TAMs shall be capable of accepting rotating shaft balances Knowing rotor thrust is a key feature of potential propfan thrust/drag bookkeeping schemes and CFD validation efforts.

• TAMs shall be capable of supporting both open- and closed-circuit model hardware design (for simulator motors based on a pneumatic power source) Different testing disciplines may be able to accept different designs for the actual nacelle and model hardware. For example, it will likely be unacceptable to Noise to test with a model featuring an open circuit propulsion simulator design (i.e., discharging propulsion simulator motor powering air into the test section, rather than ducting the powering air back through the model and out of the tunnel), but model design is considerably easier if provision for a return air path is not required.

• TAMs shall fit within the lines of a nacelle scaled for the appropriate model size for a full model transonic test Many factors influence the physical size of the wind tunnel model nacelle, but the target for motor physical sizing is an overall diameter of less than 4 inches.

• TAMs shall be capable of running at atmospheric or near atmospheric pressures in NASA Ames 11-foot wind tunnel