Analisa Pengaruh Kavitasi pada Control Valve Terhadap Getaran pada Pipa Continous Blowdown

Abstract

Vibration in piping systems is a problem that often occurs. The vibration is not only caused by the increasing of the flowrates (Flow Induced Vibration), but there are other things cause vibration such as cavitation, high frequency acoustic excitation, mechanical excitation and pulsation. On this research will be done analysis of the pipe that links between steam drum and blowdown drum that vibrates because the fluid flow through it by using Ansys simulation. Based on calculations made, obtained maximum stress von mises from modeling software ANSYS to each openings 5%, 10% and 15% is of 23802.14 Psi, Psi 21397.42 and 18154.37 Psi. The value of these three openings only 15% which is still in the allowable limits based on ASME B31.3 i.e. of 20015.20 Psi. While the value of the natural frequency of the respective openings 5%, 10% and 15% is 4.5315 Hz, 4.4222 Hz, 4.3352 Hz. Each value of the natural frequencies satisfy the limits of consent based on the standards of the DNV-RP-D101, i.e. no less than 4-5 Hz. From the analysis and modelling undertaken can be inferred that the valve openings of 15% is the most secure openings in terms of voltage and frequency naturally