Real-time Monitoring and Optimization of Geothermal Plants

This paper presents the design and implementation of a geothermal doublet digital twin which allows for several functionalities in real time: - Monitoring of doublet performance and emission - Monitoring critical processes in the production such as corrosion, erosion and scaling - Detection of events and anomalies in the production - Process...

Nano-particle dynamics during capillary suction

Due to the increased use of nanoparticles in everyday applications, there is a need for theoretical descriptions of particle transport and attachment in porous media. It should be possible to develop a one dimensional model to describe nanoparticle retention during capillary transport of liquid mixtures in porous media. Water-glycerol...

Application of variable valve actuation strategies and direct gasoline injection schemes to reduce combustion harshness and emissions of boosted HCCI engine

One of the pending issues regarding Homogeneous Charge Compression Ignition (HCCI) engines is high load operation limit constrained by excessive pressure rise rates (PRRs). The present study investigates various measures to reduce combustion harness in a residual-affected HCCI engine. At the same time, the impact of those measures on efficiency...

Natural-Fracture Reactivation in Shale Gas Reservoir and Resulting Microseismicity

A geomechanical and fluid-flow coupled model was developed to simulate natural-fracture-network reactivation during hydraulicfracturing treatments in shale gas reservoirs. The fractures were modelled using the continuum approach in a commercial finitedifference code, labeled the "softening ubiquitous joints" model, with randomly distributed...

Dynamic bayesian networks as a possible alternative to the ensemble kalman filter for parameter estimation in reservoir engineering

The objective of reservoir engineering is to optimize hydrocarbon recovery. One of the most common and efficient recovery processes is water injection. The water is pumped into the reservoir in injection wells in order to push the oil trapped in the porous media towards the production wells. The movement of the water front depends on the...

Numerical modelling of the mechanical and fluid flow properties of fault zones - Implications for fault seal analysis

Existing fault seal algorithms are based on fault zone composition and fault slip (e.g., shale gouge ratio), or on fault orientations within the contemporary stress field (e.g., slip tendency). In this study, we aim to develop improved fault seal algorithms that account for differences in fault zone composition as well as deformation conditions...

The fluid flow consequences of CO2 migration from 1000 to 600 metres upon passing the critical conditions of CO2

The minimum injection depth for the storage of CO2 is normally set at 800 metres. At and beyond this depth in the subsurface conditions exist where CO2 is in a so-called critical state. The supercritical CO2 has a viscosity comparable to that of a normal gas and a liquid-like density, Due to the high density of the supercritical CO2, storing the...

Caprock and overburden processes in geological CO2 storage: An experimental study on sealing efficiency and mineral alterations

A comprehensive set of experimental and analytical methods has been used to characterise the sealing and fluid -transport properties of fine-grained (pelitic) sedimentary rocks under the pressure and temperature conditions of geological CO2 storage. The flow experiments were carried out on cylindrical sample plugs of 28.5 or 38 mm diameter and...

Three-phase flow analysis of dense nonaqueous phase liquid infiltration in horizontally layered porous media

We considered dense nonaqueous phase liquid (DNAPL) infiltration into a water-unsaturated porous medium that consists of two horizontal layers, of which the top layer has a lower intrinsic permeability than the bottom layer. DNAPL is the intermediate-wetting fluid with respect to the wetting water and the nonwetting air. The layer interface...

Flow induced noise modelling for industrial piping systems

Noise from e.g. gas-transport piping systems becomes more and more a problem for plants located close to urban areas. Too high noise levels are unacceptable and will put limitations on the plant capacity. Flow-induced noise of valves, orifices and headers installed in the installation plays a dominant role. To control such noise problems during...

Coupled modelling of stress and fluid flow, with applications to gas extraction and disposal of energy residues

Coupled flow-stress numerical models have been increasingly used in geomechanical studies for a better understanding and more accurate prediction of subsurface behaviour due to the extraction of hydrocarbons and geological storage of energy residues. Two application studies are described demonstrating various ways of integration of the flow...

Mitigation of surface contamination from resist outgassing in EUV lithography

Contamination of optics and mask is one of the possible show stoppers for Extreme Ultraviolet Lithography. One of the important sources of hydrocarbon contamination is the outgassing of photoresist coated wafers. Due to the vacuum conditions, these hydrocarbons can freely travel to coat the first optical component they encounter. This leads to...

Application of fluid flow systems analysis to reconstruct the post-Carboniferous hydrogeohistory of the onshore and offshore Netherlands

The reconstruction of the post-Carboniferous hydrogeohistory of the onshore and offshore Netherlands is part of an ongoing TNO project on fluid flow systems analysis on geological timescales. The scope of the project is to assess the present-day hydrogeological and fluid flow conditions of the sedimentary basins in the onshore and offshore...

Solution of surface water flow equations using Clebsch variables.

Conventionally, the flow equations for surface waters are obtained by integrating vertically the basic continuum conservation equations governing three‐dimensional motion, thus reducing the problem to two dimensions. However, when vertical transport is important, this model fails, and the basic equations for three‐dimensional motion must be...