This invention relates to a force and moment balance (1) including a support (9) therefor and more specifically, but not exclusively, to a force and moment balance (1) and a support (9) therefor for a wind tunnel. Force and moment balances are known in the art and are typically used in wind tunnels to measure the force and moment loads on a model in the wind tunnel. A problem with current balances is that there is inherent vertical movement associated with horizontal force. According to the invention, the balance (1) has a fixed end (3) and a movable end (6) with a number of supports (9) between the fixed end (3) and the movable end (6). Each support (9) includes compensation means to compensate for resultant movements caused by lateral movement of the movable end (6) relative to the fixed end (3).

A balance has a balance centerline and an axial force measurement section having a longitudinal slot partially dividing the axial force measurement section into a first part and a second part longitudinally overlapping each other and interconnected by corner flexure groups. The axial force measurement section has an axial force measurement beam located approximately midway between the corner flexure groups. The axial force measurement beam has strain gages for determining axial force on the model. Each corner flexure group includes flexures each having a first flexure root and a second flexure root respectively joined to the first part and the second part. The flexures each have a flexure midpoint between the first and second flexure roots, and a flexure thickness that is tapered along the flexure length from each of the first and second flexure roots to a reduced thickness proximate the flexure midpoint.

A measurement device includes a substrate having accommodations with an emerging opening in which sensors are provided, the substrate including a cavity with a flexible printed circuit. The device is installed on a surface to characterize a fluid flow at this surface. The circuit uses hierarchized buses comprising two data communication buses emerging at the two longitudinal ends of the substrate and an internal data acquisition bus, the bus linking control circuits, each control circuit being connected to one of the communication buses, the sensors being connected to the bus in a distributed fashion on either side of each control circuit. The data from the sensors can be transmitted to the two surrounding circuits and may be acquired if one of them is faulty.

A balance has a balance centerline and an axial force measurement section having a longitudinal slot partially dividing the axial force measurement section into a first part and a second part longitudinally overlapping each other and interconnected by corner flexure groups. The axial force measurement section has an axial force measurement beam located approximately midway between the corner flexure groups. The axial force measurement beam has strain gages for determining axial force on the model. Each corner flexure group includes flexures each having a first flexure root and a second flexure root respectively joined to the first part and the second part. The flexures each have a flexure midpoint between the first and second flexure roots, and a flexure thickness that is tapered along the flexure length from each of the first and second flexure roots to a reduced thickness proximate the flexure midpoint.

A system reproduces aerodynamic boundary layer transition conditions in a wind tunnel test environment under ambient to cryogenic temperature conditions. The system includes a test component disposed in the test environment that defines an exterior surface. A trip dot is mounted on the test component and has a first state, in which a distal surface of the trip dot is at a first elevation relative to the exterior surface of the test component, and a second state, in which the distal surface of the trip dot is at a second elevation relative to the exterior surface of the test component. An actuator is operably coupled to the trip dot and configured to transition the trip dot between first and second states. A controller remotely causes the actuator to transition the trip dot between the first and second states.

A test bench for generating aerodynamic loads on an actuator to be tested includes a force actuator configured to generate at least one dynamic load, the test bench being configured to transmit the dynamic load produced by the force actuator to the actuator to be tested, and a controller for controlling the dynamic load generated by the force actuator depending on a pressure, measured by a pressure sensor, inside one of the chambers of the force actuator.

A tunable mass-damping apparatus may include a housing having an interior surface, an interior volume containing a gas, and an axis. The housing may be configured to be coupled to a wind tunnel model. The mass-damping apparatus may include a mass configured to move back and forth in the interior volume along the axis. The mass may be configured to make an airtight seal with the interior surface of the housing, thereby dividing the interior volume into an upper chamber and a lower chamber. The mass-damping apparatus may include a passage through the mass fluidly connecting the chambers and at least one spring configured to exert a position-dependent force upon the mass. The spring may be characterized by a spring constant chosen based on a natural frequency of a support structure of the wind tunnel model.

Rotary actuator assemblies, wind tunnels including the same, and associated methods are disclosed. A rotary actuator assembly includes a rotary element and a rotary actuator with a shape memory alloy element. The rotary actuator is configured to generate a first torque and a second torque in opposing rotary directions to rotate the rotary element. A rotary actuator assembly further includes an assist magnetic element and a receiver magnetic element configured to generate a magnetic force therebetween. Wind tunnels include an aerodynamic model with a rotary actuator assembly to rotate a portion of the aerodynamic model with respect to an airstream in a chamber. A method of rotating a rotary element includes modulating a temperature of a shape memory alloy element and applying a supplemental torque to the rotary element with an assist magnetic element and a receiver magnetic element.

A transducer body includes a support comprising a pair of clevis halves; a sensor body coupled to each of the clevis halves, wherein the sensor body is disposed between the clevis halves and includes a generally rigid peripheral member disposed about a spaced-apart central hub, the central hub being joined to each of the clevis halves with the peripheral member spaced apart from each clevis half, wherein at least three flexure components couple the peripheral member to the central hub, and wherein the flexure components are spaced-apart from each other at generally equal angle intervals about the central hub; and a lockup assembly configured to selectively inhibit movement of the sensor body relative to the clevis halves.

A balance protection system for a wind tunnel test system that includes a balance component, a model component connected to the balance component and a sting component connected to the balance component is disclosed. The balance protection system includes a first set of features on the model component that mate with a second of features on to the sting component. The clearances between the first and second set of features determine an amount of allowed movement of the model with respect to the balance. Actuators can be used to actively adjust the amount of clearance and respective allowed movement of the model with respect to the balance. Limiting movement of the model with respect to the balance protects the balance from damage caused by excessive forces applied to the model.