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A formulation, numerical solution technique and computer program implementing the technique are presented for the design of maximum thrust nozzles for rotational or nonequilibrium simple dissociating gas flows including boundary layer effects. The formulation is based on the usual assumptions applicable to rotational and nonequilibrium simple dissociating gas flows and on the assumption that the boundary layer is thin. The thrust is written as the integral of the stress tensor acting along the supersonic nozzle wall on which a general isoperimetric design constraint is also applied. The thrust expression is maximized by application of the calculus of variations. The resulting set of design equations are hyperbolic partial differential equations valid in the region of interest and algebraic equations specifying the boundary conditions for the Lagrange multipliers of the extremal problem. The numerical solution technique presented is based on a simplified relaxation technique which does not require numerical differentiation. The results of a brief study to determine the magnitude of the performance increases that can be expected by considering more accurate flow chemistry models are also presented. (Author), See also Volume 1, AD-862 142.

A formulation, numerical solution technique and computer program implementing the technique are presented for the design of maximum thrust nozzles for rotational or nonequilibrium simple dissociating gas flows including boundary layer effects. The formulation is based on the usual assumptions applicable to rotational and nonequilibrium simple dissociating gas flows and on the assumption that the boundary layer is thin. The thrust is written as the integral of the stress tensor acting along the supersonic nozzle wall on which a general isoperimetric design constraint is also applied. The thrust expression is maximized by application of the calculus of variations. The resulting set of design equations are hyperbolic partial differential equations valid in the region of interest and algebraic equations specifying the boundary conditions for the Lagrange multipliers of the extremal problem. The numerical solution technique presented is based on a simplified relaxation technique which does not require numerical differentiation. It is felt that this new solution technique will encourage the use of the general design formulation. The results of a brief study to determine the magnitude of the performance increases that can be expected by considering more accurate flow chemistry models are also presented. The results indicate that significant improvements may be possible. (Author)