Disclosed is a method for evaluating computational fluid dynamic simulation results. The method includes, based on a set of initial conditions, performing a first baseline run and a second baseline run of a simulated area or volume containing a vehicle body shape, and then performing a change run of the simulated area or volume containing a modified vehicle body shape, and performing the following actions within the simulated area or volume: plotting an iso line of the first baseline run and a corresponding iso line of the second baseline run, plotting an iso line of the change run that corresponds to the iso line of the two baseline runs, and comparing whether the iso line of the change run falls between the iso lines of the two basline runs. If not, then the modification to the vehicle body shape may be considered significant.

Disclosed is a method for evaluating computational fluid dynamic simulation results. The method includes, based on a set of initial conditions, performing a first baseline run and a second baseline run of a simulated area or volume containing a vehicle body shape, and then performing a change run of the simulated area or volume containing a modified vehicle body shape, and performing the following actions within the simulated area or volume: plotting an iso line of the first baseline run and a corresponding iso line of the second baseline run, plotting an iso line of the change run that corresponds to the iso line of the two baseline runs, and comparing whether the iso line of the change run falls between the iso lines of the two basline runs. If not, then the modification to the vehicle body shape may be considered significant.

A method for developing a virtual testing model of a subject for use in simulated aerodynamic testing comprises providing a computer generated generic 3D mesh of the subject, identifying a dimension of the subject and at least one reference point on the subject, imaging the subject to develop point cloud data representing at least the subject's outer surface and adapting the generic 3D mesh to the subject. The generic 3D mesh is adapted by modifying it to have a corresponding dimension and at least one corresponding reference point, and applying at least a portion of the point cloud data from the imaged subject's outer surface at selected locations to scale the generic 3D mesh to correspond to the subject, thereby developing the virtual testing model specific to the subject.

A method for developing a virtual testing model of a subject for use in simulated aerodynamic testing comprises providing a computer generated generic 3D mesh of the subject, identifying a dimension of the subject and at least one reference point on the subject, imaging the subject to develop point cloud data representing at least the subject's outer surface and adapting the generic 3D mesh to the subject. The generic 3D mesh is adapted by modifying it to have a corresponding dimension and at least one corresponding reference point, and applying at least a portion of the point cloud data from the imaged subject's outer surface at selected locations to scale the generic 3D mesh to correspond to the subject, thereby developing the virtual testing model specific to the subject.

In accordance with embodiments disclosed herein, there are provided methods, systems, and apparatuses for predicting whether a point on a computer-generated aircraft or vehicle surface is adjacent to laminar or turbulent flow is made using a transition prediction technique. A plurality of boundary-layer properties at the point are obtained from a steady-state solution of a fluid flow in a region adjacent to the point. Included in the list of boundary-layer properties are computed coefficients or weights of mode shapes that describe the boundary-layer profiles. A plurality of instability modes are obtained, each defined by one or more mode parameters. A vector of regressor weights is obtained for the known instability growth rates in a training dataset. For each instability mode in the plurality of instability modes, a covariance vector is determined, which is the covariance of a predicted local growth rate with the known instability growth rates. Each covariance vector is used with the vector of regressor weights to determine a predicted local growth rate at the point. Based on the predicted local growth rates, an n-factor envelope at the point is determined.

In accordance with embodiments disclosed herein, there are provided methods, systems, and apparatuses for predicting whether a point on a computer-generated aircraft or vehicle surface is adjacent to laminar or turbulent flow is made using a transition prediction technique. A plurality of boundary-layer properties at the point are obtained from a steady-state solution of a fluid flow in a region adjacent to the point. Included in the list of boundary-layer properties are computed coefficients or weights of mode shapes that describe the boundary-layer profiles. A plurality of instability modes are obtained, each defined by one or more mode parameters. A vector of regressor weights is obtained for the known instability growth rates in a training dataset. For each instability mode in the plurality of instability modes, a covariance vector is determined, which is the covariance of a predicted local growth rate with the known instability growth rates. Each covariance vector is used with the vector of regressor weights to determine a predicted local growth rate at the point. Based on the predicted local growth rates, an n-factor envelope at the point is determined.

Rotary actuator assemblies and associated methods are disclosed. The rotary actuator assemblies include a rotary actuator, a rotary element, and a magnetic element. The rotary actuator is configured to generate a torque. The rotary element is coupled to the rotary actuator and is configured to rotate responsive to receipt of the torque. The magnetic element is configured to bias the rotary element in a rotary direction. The methods include rotating a rotary element responsive to receipt of a torque from a rotary actuator and applying a supplemental torque to the rotary element with a magnetic element.

Rotary actuator assemblies and associated methods are disclosed. The rotary actuator assemblies include a rotary actuator, a rotary element, and a magnetic element. The rotary actuator is configured to generate a torque. The rotary element is coupled to the rotary actuator and is configured to rotate responsive to receipt of the torque. The magnetic element is configured to bias the rotary element in a rotary direction. The methods include rotating a rotary element responsive to receipt of a torque from a rotary actuator and applying a supplemental torque to the rotary element with a magnetic element.

Methods of damping vibrations in a host structure are described. In one embodiment, the vibrations can be damped using a tuned mass damper. The tuned mass damper can include a suspended mass with magnets which is configured to move in response to current being applied to a voice coil. The tuned mass damper can damp vibrations resulting from an external load applied to the host structure, such as an external aerodynamic load. In one embodiment, the tuned mass damper can be mounted within a wind tunnel model undergoing transonic testing. The tuned mass damper can be operated to limit potentially destructive vibrations which can occur during testing.

A wind field dynamic downscaling method based on aerodynamic parameters of simplified terrain, the method comprises steps of: numerically simulating the simplified terrain based on computational fluid dynamics to obtain the aerodynamic parameters of the simplified terrain; redistributing the wind speed at the corner point of a mesoscale grid within the downscaling grid based on terrain elevation data, land use type data and the aerodynamic parameters, to implement the wind field downscaling calculation. It is based on the aerodynamic parameters of the two-dimensional simplified terrain, and a new wind field dynamic downscaling scheme is designated by adding the high-resolution terrain elevation data and the land use type data.