Background | The discipline of adjusting wind tunnel data for wall boundaries has been in practice almost as long as wind tunnels have been in existence. Demand for more accurate data has continued to push the development of correction methodologies and boundary representation. Additionally, more emphasis has been placed on the validation of computational tools for use in vehicle design and analysis, with the intent to significantly reduce the number of ground tests required to verify a concept. Better correction methods used in ground testing would lead to improved accuracy in the prediction of aerodynamic behavior of future aircraft systems designed for military operations. For example, transport aircraft tend to have large blunt tails that have a tendency to separate easily and advancement in propulsion systems have moved installed systems away from conventional axially directed thrust.
In 1995 The AGARD Fluid Dynamics Panel planned what became AGARDograph 336 which was published in 1998 as a sequel to 1966 publication of AGARDograph 109. Although both of the documents still contain valid information, the requirements placed on the field of wall interference are increasingly stringent in alignment with computational prediction and validation requirements. Correction is still appropriate for certain kinds of production tests, but understanding the interference itself is more appropriate for CFD validation activities. The move to more CFD based design has reduced the demand for testing, and as a result, support of specialists in this area have diminished. It has been 16 years since the last AGARDograph in this area and only one or two of the authors of this document continue to practice in the discipline. The same can be said of the international community that once existed around this topic area.
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