In real life, airflow in a turn is curved, how does a wind tunnel simulate this condition?
If we just yaw the test object at some angle in wind tunnel, do we simulate the airflow in correct way?
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Wind tunnel is a tool to interrogate aerodynamics, not to investigate flight dynamics (which relies on aerodynamic results to predict vehicular dynamics). As explained in this answer, the additional aerodynamic effects from induced airflow due to rotation can be lumped into dynamic derivative coefficients. Some examples include:
etc. Note that the rates in these derivatives are expressed in dimensionless rates to maintain similitude, which is accomplished by dividing the body rates by $bV_\infty/2$, where $b/2$ is half span and $V_\infty$ is freestream speed.
To estimate dynamic derivatives in wind tunnel, the forced-oscillation method is typically applied. The model is excited in a single axis by a small amplitude sinusoid at representative range of dimensionless rates and reduced frequency. This paper provides a good introduction to the data collection and analysis.
Rotary balance tests can also performed in wind tunnel to measure the effect of sustained rotary motion whose angular velocity is coincident with the air velocity vector. These tests are mainly to explore spin characteristics, which occur at very high angles of attack and sideslip. Forced-oscillation method would not be adequate in these conditions.