In this report, a method for simulating interactive height-field based water on a parallel architecture is presented. This simulation is designed for faster than real time applications and is highly suitable for video games on current generation home computers. Specifically, the implementation proposed in this report is targeted at the Sony PlayStation 3. This platform requires code to be both highly parallelized and data oriented in order to take advantage of the available hardware which makes it an ideal platform for evaluating parallel code. The simulation captures the dispersive property of water and is scalable from small collections of water to large lakes. It also uses dynamic Level Of Detail to achieve constant performance while at the same time presenting high fidelity animated water to the player. This report describes the simulation method and implementation in detail along with a performance analysis and discussion.

Background:  As time moves on hardware is able to tackle heavier and more complex computations in real-time systems. This means that more realistic and stylistic environments can be computed. One of these environments is the ocean. To simulate ocean water in real-time, procedural methods such Gerstner waves and Fast Fourier Transformation (FFT) have been developed.    Objectives: The primary objective of this thesis is to compare two procedural methods that are designed to simulate realistic ocean water waves. Meanwhile, the goal of this thesis is for developers to gain an insight into these two methods used in order to simulate realistic ocean water waves. Additionally, it will also discuss advantages as well as disadvantages with both, which gives developers a thorough understanding of the most appropriate method for implementation.  Methods: FFT and Gerstner waves will be implemented in order to perform comparisons of resources, computation time and Video Random Access Memory (VRAM). The procedural methods will be calculated on the GPU and measured using DirectX 11 query interface. Lastly, the final step is to gather data from the CPU side, and store the metrics for time it took to render a frame and scalability of the displacement maps. \noindent\textbf{Results}.The profiling and experiments showed that FFT is more computationally intensive and requires more VRAM. For scalability, FFT also scales worse in terms of both computation time and VRAM usage. Conclusions: From the results we can conclude that FFT is more computationally heavy and requires more VRAM usage than Gerstner waves. In none of the tests did the computation time of Gerstner waves take longer than FFT. Depending on grid resolution, FFT took 4-16 times longer to compute than Gerstner. Even though Gerstner waves takes less time to compute, for smaller grids, less than 512x512, the difference is less than 0.2ms.

Yes / Key to progress in molecular simulation is the development of advanced models that go beyond the limitations of traditional force fields that employ a fixed, point charge‐based description of electrostatics. Taking water as an example system, the FFLUX framework is shown capable of producing models that are flexible, polarizable and have a multipolar description of the electrostatics. The kriging machine‐learning methods used in FFLUX are able to reproduce the intramolecular potential energy surface and multipole moments of a single water molecule with chemical accuracy using as few as 50 training configurations. Molecular dynamics simulations of water clusters (25–216 molecules) using the new FFLUX model reveal that incorporating charge‐quadrupole, dipole–dipole, and quadrupole–charge interactions into the description of the electrostatics results in significant changes to the intermolecular structuring of the water molecules. / EPSRC. Grant Number: K005472

In this work, we wish to determine the free energy landscape and the nucleation rate associated with the process of homogeneous ice nucleation. To do this, we simulate the homogeneous nucleation of ice with the mW monatomic model of water and with all-atom models of water using primarily the umbrella sampling rare event method. We find that the use of the mW model of water, which has simpler dynamics compared to all-atom models of water, but is nevertheless surprisingly good at reproducing experimental data, results in very reasonable agreement with classical nucleation theory, in contrast to some previous simulations of homogeneous ice nucleation. We suggest that previous simulations did not observe the lowest free energy pathway in order parameter space because of their use of global order parameters, leading to a deviation from classical nucleation theory predictions. Whilst monatomic water can nucleate reasonably quickly, all-atom models of water are considerably more difficult to simulate, primarily because of their slow dynamics of ice growth and the fact that standard order parameters do not work well in driving nucleation when such models are being used. In this thesis, we describe a local, rotationally invariant order parameter that is capable of growing ice homogeneously in a biassed simulation without the unnatural effects introduced by global order parameters, and without leading to non-physical chain-like growth of 'ice' clusters that results from a naïve implementation of the standard Steinhardt-Ten Wolde order parameter. We have successfully used this order parameter to force the growth of ice clusters in simulations of all-atom models of water. However, although ice growth can be achieved, equilibrating simulations with all-atom models of water is extremely difficult. We describe several approaches to speeding up the equilibration in all-atom models of water to enable the computation of free energy profiles for homogeneous ice nucleation.

Final thesis, elaborated within the master study field of Foundry technology, deals with determination of some parameters of ceramic foam filters that are necessary for using numerical simulation during foundry practice. Thesis foccuses on defining methodology, manufacturing messuring device and measuring pressure drop on several type sof ceramic foam filters in dependence on flow rate of measuring medium. Measuring medium selected is water, mening this thesis deals also with water simulation in foundry technology.

This work deals with design and implementation of simple demonstration aplication for simulation of a water flow on irregular terrain. The work examines essential building blocks of the simulation. It also suggests approaches that can be used to optimize and/or extend used method.

DICE, a Swedish game company, wanted a more realistic water simulation. Currently, most large scale water simulations used in games are based upon ocean simulation technology. These techniques falter when used in other scenarios, such as coastlines. In order to produce a more realistic simulation, a new one was created based upon the water simulation technique "Wavefront Parameter Interpolation". This technique involves a rather extensive preprocess that enables ocean simulations to have interactions with the terrain. This paper is about optimizing the current implementation of DICE's water simulation. The goal is to achieve better runtime GPU performance. After implementing various optimizations, a speedup of roughly 4-6x was achieved. Performance was evaluated on the PlayStation 4 gaming console. / DICE, ett svenskt spelföretag, ville ha en mer realistisk vattensimulering. Det flesta storskalna vattensimuleringar som används i spel idag är baserade på havsvattensimuleringstekniker. Dessa tekniker fungerar inte lika bra i andra scenarier, som t.ex. kustlinjer. För att kunna få en mer realistisk simulation, skapades en ny simulation baserad på vattensimuleringstekniken Wavefront Parameter Interpolation. Denna simuleringsteknik involverar en lång förprocess som ger havsvattensimuleringar möjligheten att interagera med terräng. Denna uppsats handlar om att optimera den nuvarande implementationen av DICEs vattensimulering. Målet är att få bättre grafikprestanda under körtid. Efter att olika optimiseringar hade implementerats, blev programmet 4-6x gånger snabbare. Prestandan utvärderades på spelkonsolen PlayStation 4.