Question

What is the other name of the top-hat filter?

(a) Cross filter

(b) Cube filter

(c) Box filter

(d) Square filter

The question was posed to me during an interview for a job.

Query is from Large Eddy Simulation for Turbulent Models topic in chapter Turbulence Modelling of Computational Fluid Dynamics

Answer 1

The correct answer is:

(c) Box filter

Explanation:

The top-hat filter is often referred to as a box filter. It is used in signal processing and numerical simulations to smooth or average a signal or field. In the context of large eddy simulation (LES), the top-hat or box filter is applied to resolve large-scale turbulent structures while filtering out smaller, unresolved turbulence features. The filter's name comes from its shape, which resembles a box or rectangular window.