# One-Dimensional Fluid-Structure Interaction Models in Presurized Fluid-Filled Pipes: A Review
## 4 Engineering Applications
### Anchor and Support Forces  
Fluid-Structure Interaction and especially the behaviour of pipe supports have a direct applicability in above-ground or non-buried pipe systems, such as hydropower systems, long oil and gas pipes, cooling systems of nuclear, thermal plants or any fluid distribution system in industrial compounds. However, only a few authors investigated anchor and support behaviour in the context of water-hammer theory. Frequently, studies are based on qualitative discussions focused on post-accident analyses and mitigation measures case-by-case oriented. An example is [152] where recommendations for design criteria, operating rules and post-accident analyses were given. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Industry** & **Application** & **International Standards** \\ \hline \multirow{3}{*}{Hydropower energy} & \multirow{3}{*}{penstocks} & ASME-B31.3 \\  & & DIN-19704-1 \\  & & ASCE MOP 79 \\  & & CECT-1979 \\ \hline \multirow{2}{*}{Nuclear/Thermal energy} & \multirow{2}{*}{cooling systems} & ASME-BPV \\  & & NS-G-1.9 \\ \hline \multirow{2}{*}{Oil/Gas transportation} & \multirow{2}{*}{oil/gas mains} & ASME-B31.2 \\  & & ASME-B31.4 \\  & & ISO-13628 \\ \hline \multirow{2}{*}{Water distribution} & \multirow{2}{*}{water pipes} & ANSI/ ASME-1010 \\  & & PDI-WH 201 \\ \hline \multirow{2}{*}{Aerospace} & \multirow{2}{*}{fuel pipes} & ISO/FDIS-8575 \\  & & NASA-STD-8719 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Codes and Standards in industries where water–hammer analyses are frequent. In addition, [PERSON]. [153; 154; 155] presented qualitative discussions of the performance of different industrial piping systems, giving insights into pipe support behaviour. The latter highlighted the case-by-case dependency of Fluid-Structure Interaction and the high computational demand of including anchor analyses, stating that the scope of such studies should be justifiable only for very critical systems, such as in nuclear power plants. Data from a firewater facility pipeline was collected in [10], who carried out numerical analyses by means of MOC. The effect of support rigidity of pipe systems was studied by [156] and discussed for what rigidity of the supports FSI becomes a dominant effect. In their analysis, they applied both classic water-hammer theory and a MOC-FEM approach by means of the FLUSTRING code [71; 127]. The simulated facility corresponded to the one from Delft Hydraulics laboratory. A study of the effect of a pipe-rack considering the dry friction occurring between the rack and the pipe-wall was carried out in [157]. Recommendations were given in order to assess when dry friction must be considered. Following this line, Refs. [57; 99; 158] carried out experimental and numerical work based on a straight copper pipe which allowed a broad variety of anchoring configurations. In [57], a robust and accurate MOC-MOC code to simulate anchoring blocks taking into account their inertia and dry friction was presented. The blocks were nested in the numerical scheme as internal conditions and junction coupling was considered. Figure 12 depicts the model output vs. experimental measurements for different anchoring set-ups. Different anchoring conditions were assessed in [124] using CFD software, which was validated by means of experimental data. The analysis pointed out the need for CFD simulations for the proper description of pipe support behaviour. In [159], the aim was the simulation of hydraulic transients in a straight pipe anchored with axial supports using an MOC-FEM approach. Both pipe-wall and supports had a viscoelastic behaviour. The study concluded that the viscoelastic supports significantly reduce displacements and stresses in the pipe and eliminate the high-frequency fluctuations produced due to FSI. A multi-span pipe system, with rigid constraints in the middle s  
Figure 12: Validation of the numerical model developed in [57] for: anchored pipe ends (**a**); released downstream end (**b**); and released downstream end but anchored midstream (**c**).