DEV GORUR RAJNARAYAN
Pilots at Beaume Ct, Mountain View, CA
License number
California A4928712
Issued Date
Oct 2014
Expiration Date
Oct 2019
Category
Airmen
Type
Authorized Aircraft Instructor
Address
Address
439 Beaume Ct, Mountain View, CA 94043
Professional information
Predicting Transition From Laminar To Turbulent Flow Over A Surface Using Mode-Shape Parameters
US Patent:
2013028, Oct 24, 2013
Filed:
Mar 26, 2013
Appl. No.:
13/850628
Inventors:
Dev Rajnarayan - Mountain View CA, US
Peter Sturdza - Redwood City CA, US
Peter Sturdza - Redwood City CA, US
Assignee:
AERION CORPORATION - Reno NV
International Classification:
G06F 17/50, G06N 99/00
US Classification:
706 12
Abstract:
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.
Predicting Transition From Laminar To Turbulent Flow Over A Surface
US Patent:
2012024, Sep 27, 2012
Filed:
Mar 22, 2011
Appl. No.:
13/069374
Inventors:
Dev RAJNARAYAN - Mountain View CA, US
Peter Sturdza - Redwood City CA, US
Peter Sturdza - Redwood City CA, US
Assignee:
DESKTOP AERONAUTICS, INC. - Palo Alto CA
International Classification:
G06G 7/57
US Classification:
703 9
Abstract:
A prediction of whether a point on a computer-generated 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. 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.