Flow indicators are fundamental for anyone working in the context of projects related to noise reduction of pressurized fluid networks.

The prediction of aerodynamic noise of various industrial process control valves is possible with the simulation software SILDIS® [1], given earlier developments, the calculation necessitating to have, as available input data, flow indicators that influence the intrinsic mechanical power, the dominant frequency of the noise and therefore the total internal sound power level.

But it not always possible to get from manufacturers of industrial process control valves information reflecting (accurately, completely and in an immediately interpretable form) the particular situation for which a soundproofing device is considered (or even for which a simple sound impact evaluation is wished) as a part of a project, which is a serious obstacle to the analysis and design works to be conducted.

In some cases, data being fragmented and based on unspecified methodologies are made available, however being not suitable for sizing a silencer or pipe lagging or even for the performance of sound decay calculations in good conditions.

ITS has integrated to the simulation software SILDIS® the calculation of flow indicators for the prediction of industrial processes control valves aerodynamic noise.

Calculation routines have been implemented to calculate the various parameters related to the liquid pressure recovery and to piping geometry (total pressure loss determination is a step of the computation), as well as to evaluate the discharge coefficient of a control valve with attached fittings (upstream: reducer, downstream: expander). Checking the turbulent nature of the flow (practical usual case), basing some assessments, can be performed with the software on the basis of the comparison to a reference value of the Reynolds number which is also an output data of the simulation.

Following the operations of modification of acoustics calculation software SILDIS®, comparison of simulation results with bibliographic data (measurement results, results of calculation by others, ...) showed good agreement for many combinations of those parameters influencing the noise emissions of industrial processes control valves.

The consequence expected from improvements in simulation software SILDIS® (for the calculation of flow indicators) is the ability to refine the prediction of industrial processes control valves aerodynamic noise.

[1] SILDIS® Module 8C prediction of control valves aerodynamic noise