초록 ▼

A computer method of simulating a fluid flow in an aircraft environment to determine at least one aerodynamic coefficient, comprising obtaining a first series of values of the aerodynamic coefficient. The method also includes defining a criterion for convergence of said aerodynamic coefficient, sele

A computer method of simulating a fluid flow in an aircraft environment to determine at least one aerodynamic coefficient, comprising obtaining a first series of values of the aerodynamic coefficient. The method also includes defining a criterion for convergence of said aerodynamic coefficient, selecting a determined set of terms belonging to said first series, defining a monotonic function configured to make a relatively expanding transformation in said determined set relative to the complement of said set, applying said monotonic function on said first series to form a second series of values of the aerodynamic coefficient, determining said aerodynamic coefficient by plotting a variation curve representative of said second series of values of the aerodynamic coefficient, and displaying said variation curve including an intrinsic zoom of the convergence zone of said aerodynamic coefficient.

대표청구항 ▼

1. A computer-implemented method, using a computer processor, comprising: simulating a fluid flow in an aircraft environment to determine at least one aerodynamic coefficient characterizing an aerodynamic behavior of at least one element of the aircraft;providing a digital solution of equations mode

1. A computer-implemented method, using a computer processor, comprising: simulating a fluid flow in an aircraft environment to determine at least one aerodynamic coefficient characterizing an aerodynamic behavior of at least one element of the aircraft;providing a digital solution of equations modelling the fluid flow in said aircraft environment, according to a model configured using physical parameters of the fluid flow, said digital solution being made iteratively to obtain a first series of values of the aerodynamic coefficient indexed by a number of iterations;defining a criterion for convergence of said aerodynamic coefficient using processing means;selecting a determined set of terms belonging to said first series of values of the aerodynamic coefficient, as a function of said convergence criterion, using the processing means;defining a monotonic function configured to make a relatively expanding transformation in said determined set relative to a complement of said set, using the processing means, the transformation being contracting outside said set;applying said monotonic function on said first series to transform into a second series of values of the aerodynamic coefficient, said second series defining a global change to said aerodynamic coefficient with a local expansion in a convergence zone corresponding to said determined set, using the processing means;determining said aerodynamic coefficient by plotting a variation curve representative of said second series of values of the aerodynamic coefficient as a function of the number of iterations, using the processing means; anddisplaying said variation curve including an intrinsic zoom of said convergence zone giving details of the convergence of said aerodynamic coefficient, on output means,wherein a plot of said variation curve includes variations indexed by the number of iterations. 2. The method according to claim 1, wherein said convergence criterion is defined as a function of a predetermined number of iterations. 3. The method according to claim 2, wherein the predetermined number of iterations corresponds to a total number of iterations. 4. The method according to claim 1, wherein a cardinality of said determined set is defined as a function of a predetermined order of magnitude of the aerodynamic coefficient. 5. The method according to claim 1, wherein said monotonic function corresponds to a mixed linear-logarithmic transformation with a linear behavior in said determined set and a logarithmic behavior outside said set, defined as follows: F⁡(x)=x10p⁢⁢if⁢⁢x≤10p⁢⁢andF⁡(x)=sign⁡(x)·log10⁡(x10p-1)⁢⁢if⁢⁢x>10pwhere p is an order of magnitude of precision, and x is said aerodynamic coefficient. 6. The method according to claim 2, further comprising adding a constant to each term in the first series before application of said monotonic function, said constant being equal to the value of the aerodynamic coefficient at a determined number of iterations. 7. The method according to claim 6, further comprising applying an absolute value operation on the terms of said second series to transform into a third series of positive terms. 8. The method according to claim 7, further comprising the following steps: applying an oscillation filtering operation on said third series to transform into a fourth monotonic series; andplotting a positive and monotonic variation curve representative of said fourth series. 9. The method according to claim 5, further comprising the following steps: plotting a preliminary variation curve C0(I) representative of said first series of values of the aerodynamic coefficient as a function of the number of iterations,defining at least one interval of values of the aerodynamic coefficient corresponding to said determined set,applying said mixed linear-logarithmic monotonic function on said preliminary variation curve operating a linear transformation inside said interval and a logarithmic transformation outside said interval to form said variation curve. 10. The method according to claim 9, further comprising the steps: calculating a final value C0final=C0(Imax), a maximum value C0max=max(C0(I)), and a minimum value C0min=min(C0(I)) of said preliminary variation curve C0(I),recursively defining a fifth decreasing series I0p, I0p+1, . . . , I0i, . . . , I0m−1, I0m such that I0i>C0min∀iε[p, m−1], I0m≦C0min, I0p=M0p−10p, and M0p≦C0final to the nearest 10p, where p is an order of magnitude of precision,recursively defining a sixth increasing series S0p, S0p+1, . . . , S0i, . . . , S0n−1, S0n, such that S0i