Hydraulics, simulation

Figure 45. Example of a hydraulic simulation with 2 groups of wells, 7 warm and 7 cold, rim with a flow rate of 32 1/s. The simulation is done with MODFLOW. Figures in meter. The distance between the well groups are 150 m (see also Figure 46)...

The use of compaction simulators was first reported in 1976. Since then, a variety of simulators have been developed. Hydraulic simulators, as well as mechanical simulators, are available to characterize raw materials, drug substances, and formulations, as well as to predict material behavior on scale-up. The appeal of simulators is due to the fact that they purport to provide the same compaction profile as experienced on a tablet press while using only gram or even milligram quantities of powders. Compaction simulators can achieve high speeds, as would be experienced on a production tablet press, and can be instrumented to measure a variety of parameters, including upper and lower punch force, upper and lower punch displacement, ejection force, radial die wall force, take-off force, etc. Summaries on the uses of simulators and tablet press instrumentation can be found in (19,20). 

The hydraulic simulation tool AMESim (2006) has also been extended for exhaust aftertreatment simulation, by including routines developed together with IFP (2006). The software includes models for TWC, hydrocarbon (EIC) trap, NSRC, oxygen storage, DOC and DPF as well as pipes, etc. Catalysts are modeled via 0D approach, hence all transport effects are lumped into reaction kinetic parameters. These kinetic parameters can be adapted by the user. 

The final step in the hydrologic transport of radioactive aerosols through a watershed is transmission through the channel system to the basin outlet. Aerosol input to the main channels in the basin from land surface runoff and interflow must pass through the channel system in a manner governed by the laws of hydraulics. Simulation of the timing of radioaerosol outflow from the basin must therefore include a consideration of channel transport. 

Ayeni, K. Osisanya, S.O. Evaluation of Commonly Used Fluid Rheological Models Using Developed Drilling Hydraulic Simulator in Proc. 5th Canadian International Petroleum Conference, The Petroleum Society Calgary,... 

Using an instrumented punch to collect force data is cumbersome because it is limited to a particular punch size and shape. Recalculation to pressure values is not always adequate. One can, however, monitor and record force waveform from a properly calibrated R D grade compression transducer. Once the production press brand, model, speed, and tooling are specified, a waveform can be recorded and then fed into hydraulic simulator. 

Figure 4 shows the comparison carried out between the measured and simulated pressures. The general shape of the curves obtained with hydraulic simulation is quite similar to measurement results, except there is a constant difference of about 1 bar between the P4 measurements and the simulation. This point will be discussed in Section 4.5 below. Our simulation approach (a hydraulic steady flow analysis with four steady-state steps) was not able to reproduce pore pressure increase (led to a higher horizontal stress than vertical stress) as excavation neared the monitored borehole intervals and as post-tunnel face dissipation was completed. 

Lineup of three diti nsional thermal hydraulics simulation is a finite difference method code AQUA SPLASH based on Arbitrary-Eulerian-Lagrangian finite element method and direct simulation code DINUS-3. The AQUA code is being applied to natural circulation and thermal stratification analysis. The SPLASH mostly simulates the free surface phenomena. The DINUS-3 code simulates thermal striping phenomena. Validations of these codes are almost completed and practical problems are currently solved. 

Thermal-hydraulics in fuel subassemblies are analyzed using subchannel code ASFRE for single phase flow and SABENA for two-phase flow. The ASFRE code is currently under validation study using PNCs sodium experiment data mentioned above. Although there is little activity regarding the SABENA code, it is ready for utilization in the safety evaluation of demonstration FBR. What is noted in this reporting period is a new finite element code SPIRAL for thermal-hydraulic simulation inside the friel bundle surrounded by extremely complicated geometry. The new code will be used for more microscopic temperahire and flow field analysis in the fuel assembly that will be required in the local fault evaluation. 

Once the different time windows have been determined by using thermal-hydraulic simulations, these should be evaluated in terms of HEP. 

According to the HR modelling explained above, two techniques have been employed to lead the HRA, including it in the LPSA. On the one hand, for the diagnosis phase, the TRC method has been used. The direct influence of the different time windows extracted from thermal hydraulics simulations is directly reflected in the HEP quantification achieved by this technique. On the other hand, the manual or response phase has been carried out by using the THERP method. 

Sensitivity HEP case (CT = Ih) it is possible to start the remaining RHR train with a HEP modeling as explained in Section 4.3, using the available times of thermal hydraulics simulations. CT is the same as the base case (CT = 1 hour). 

Wang, G., Li, W., Li, N., Han, S., 2015. Thermal-hydraulic simulation for pebble-bed fluoride salt-cooled high temperature reactor core. Atomic Energy Science and Technology 49. 

The SSC-K code [4] has been developed by KAERI for the analysis of system behaviour during transients. The SSC-K code features a multiple-channel core representation coupled with a point kinetics model with reactivity feedback. It provides a detailed, one-dimensional thermal-hydraulic simulation of the primary and secondary sodium coolant circuits, as well as the balance-of-plant steam/water circuit. 

Accurate site investigation data with test drillings and pumping tests are also of importance for modelling and simulations to be used for permit applications. The simulations are used to predict the thermal and hydraulic influences and are used for environmental assessment issues as well as for prediction of potential physical damages caused by the pumping of ground water. 

The hydraulic impact will be more or less extensive depending on the distance between the groups of wells. With a long distance the impacted area will be larger than for a shorter distance. In Figure 45 an example from a simulation at Bo 01 in Malmo, Sweden is shown. 

U.S. EPA s rationale for the requirement of composite bottom liner option in the final doubleliner rule is based on the relative permeability of the two liner systems.13 The results of numerical simulations performed by U.S. EPA,10 which compared the performance of a composite bottom liner to that of a compacted soil bottom liner under various top liner leakage scenarios, showed that liquids passing through defects in the top FML enter the secondary LCRS above the bottom liners. The hydraulic conductivities of bottom liner systems greatly affect the amount of liquids detected, collected, and removed by the secondary LCRS. 

To understand the physical mechanisms of flow boiling crisis, simulated tests have been conducted to observe the hydraulic behavior of the coolant and to measure the thermal response of the heating surface. To do this, the simulation approaches of the entire CHF testing program are considered as follows. 

In the microscopic analysis of CHF, researchers have applied classical analysis of the thermal hydraulic models to the CHF condition. These models are perceived on the basis of physical measurements and visual observations of simulated tests. The physical properties of coolant used in the analysis are also deduced from the operating parameters of the test. Thus the insight into CHF mechanisms revealed in microscopic analysis can be used later to explain the gross effects of the operating parameters on the CHF. 

Simulate hydraulic behavior Prepare to simulate advection Simulate conservative constituents Simulate water temperature... 

Ahmed, U., et al. "Effect of Stress Distribution on Hydraulic Fracture Geometry A Laboratory Simulation Study in One Meter Cubic Blocks," SPE/DOE paper 11637, 1983 SPE/DOE Symposium on Low Permeability, Denver, March 14 16. 

Acharya, A. and Kim, C.M. "Hydraulic Fracture Treatment Design Simulation for the Rotliegendes Formation," SPE/DOE paper 16414, 1987 SPE/DOE Low Permeability Reservoirs Symposium, Denver, May 18-19. 

Lam, K.Y., Cleary, M.P., and Barr, D.T. "A Complete Three-Dimensional Simulator for Analysis and Design of Hydraulic Fracturing," 1986 spe Unconventional Gas Technology Symposium, Louisville, May 18-21. 

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