Abstract: As ocean models improve, assimilation of data with the help of models becomes increasingly important. The Kalman filter provides a method for assimilation of data that are arbitrarily distributed in time and space and have ...

Abstract: Every supersonic fan or compressor blade row has a streamtube, the “sonic streamtube,” which operates with a blade relative inlet Mach number of one. A key parameter in the design of the “sonic streamtube” is the area ratio ...

Abstract: Reaction is the fundamental parameter by which the asymmetry of the velocity triangle of a stage is set. Little is understood about the effect that a reaction has on either the efficiency or the operating range of a ...

Abstract: Breaking down the total loss in a turbomachine into a number of low-order, physical models is a powerful way of developing loss models for informing design decisions. Better loss models lead to better design decisions. A ...

Abstract: This paper describes a simple and efficient physics-based method for designing optimal transonic multistage compressor rotors. The key to this novel method is that the spanwise variation of the parameter which controls the ...

Abstract: The operating range of a compressor is usually limited by the rapid growth of three-dimensional (3D) separations in the endwall flow region. In contrast, the freestream region is not usually close to its diffusion limit ...

Abstract: Three-dimensional design is central to all modern compressor design systems, but many of these methods still rely on a two-dimensional and sectional view of aerodynamics at their core. This paper argues that this view ...

Abstract: Advanced data assimilation methods are applied to simple but highly nonlinear problems. The dynamical systems studied here are the stochastically forced double well and the Lorenz model. In both systems, linear approximation ...

Abstract: An analysis of variational data assimilation schemes for linear dynamical forecast models shows that the penalty functional must include an explicit contribution from the initial conditions in order to ensure a unique, ...

Abstract: We performed a comparative verification of Model Output Statistics (MOS) against Generalized Exponential Markov (GEM), a single station forecasting technique which uses only the surface observation and climatology as input. ...