Case Studies

Challenging to imagine now, looking at the horizontal rain outside, that solar heating and wind cooling simulations will ever be relevant in London. But the truth is that weather and comfort simulation together with shading design are all important aspects of modern urban planning. In countries with warmer climate than the UK, it is essential to include surface temperature of structures in the design parameters. And much sooner than we hope, it will be essential in some parts of the UK as well. ...

Thermal comfort analysis of an office is not much different from simulating the ventilation system of a car park. What puts these analyses into a different perspective is the need for determining occupant comfort. Cars do not complain about draught and cold feet, do they? A comfort analysis is especially important if the office floor takes many occupants. I have seen layouts where hundreds of people sit side by side for the whole day. Obviously their comfort is of top priority to the employer. I...

As detailed in one of our case studies, a data centre CFD simulation project provides interesting fluid dynamics and thermal design challenges. The data hall however is not the only part of the critical infrastructure that needs heat transfer analysis. Cooling of the server and battery room requires an outdoor condenser plant. As this is exposed to elements, the environment influences its cooling performance. The goal of a condenser plant environmental CFD simulation is to tell if the designer c...

Data centres are serving almost every aspect of our lives. No social media or online meeting without them. As some refurbished industrial units house computing facilities instead of say machine shops it even affects the building industry. But jamming racks and coolers into a building that was not designed from the ground up for this has risks. These risks can expand to the external environment of the building. Micro-climate of a densely build area can adversely effect the operation of the data c...

The most challenging bit in every aircraft aero CFD simulation is the proper aircraft geometry. I am sure you have seen fancy CFD simulation results of all sorts of fighter and other aircraft. Believe me, these may only be approximations, nothing more. I know from experience it is extremely difficult get the accurate geometry of a real aircraft. Be it commercial, not to mention military. And if you got the real model, that is for the given job and for that job only. No posts to social media for ...

You may well remember from the previous episode of the servo motor electronics CFD simulation that we had a small vertical pcb card with two silicon chips, which were feeling quite hot under the casing. These chips nearly reached the blazing 90°C when the ideal would be 60 or below. I had to do something to reduce their temperature. The original design criteria stated that no fans to be used due to noise issues. So here is what I tried as the first step in the design process. Video showing simu...

When car park ventilation systems are designed, building regulations in the UK set two major requirements. The designer should provide at least 2.5% of the floor area as free opening. The designer also should choose a mechanical ventilation system that is capable of at least 3 air changes per hour. A car park ventilation CFD simulation could reveal however that apart from the regulation numbers there are other factors that influence performance. Fluid dynamics simulation of mechanical ventila...

Looking for an industrial equipment to show fluid flow and heat transfer simulations in a very visual way? Then a mixing tank seems to be an ideal choice. It is because motion and multiphase are all part of these machines' daily job. Also because we can demonstrate these two interesting software features at the same time. This case study presents the recording of a mixing tank CFD simulation webinar which Dr Steff Evans from Evotech CAE and I did earlier. Mixing tank webinar This recoding cont...

When doing CFD simulations of industrial machinery, sometimes a furnace or a casting machine smoke extraction system never come to life due to changes in project budget or focus. Unfortunately in these cases you cannot get feedback about the accuracy of the CFD results as you have no measured data to compare with. For building elements like louvres, this is rarely the case. Especially if the louvre is small enough so it gets easily built and sent to physical prototype tests. Advanced Ventilation...

Modern day comfort like temperature and humidity control in buildings require high-tech heating, ventilation and air conditioning (HVAC) machinery. As rain and sand are regular additives to air, HVAC engineers use louvres to keep the unwanted bits out. To help HVAC engineers we have worked out a louvre performance simulation method that can predict the most important features of this building element. So louvres must keep rain and sand out but at the same time these should not mean too much r...

When thinking about electronics, all of us would mention computers, mobile devices or electric cars. However, from electronics thermal simulation viewpoint there are some really nice examples among industrial applications as well. The subject of this application example comes from a medical imaging machine. Its job is to control several servo motors of the patient table. It works in a closed compartment and it needs a well designed air ventilation system to ensure that temperature of delicate el...

Once the technical director of a company that engineers HVAC systems for the built environment asked me, when the time would come for the computer simulations to make traditional engineering calculations and design methods completely outdated? As far as I see it, computer simulations and engineering experience should walk hand-in-hand. More to that, I think simulations will not make fast hand calculations obsolete either. My view has been confirmed by one of our fluid dynamics motion simulation ...

In the previous part I showed how we made the smoke extraction CFD modelling of the original system of the casting machine. That machine produced many hundreds of cylinder head castings in a shift. In that simulation, which represented the first step of the development project, we created the characteristic, time dependent pattern of smoke generation and validated against real life operation of the machines. The thick white smoke the casting assembly emits has to be handled by an extraction syst...

We have already published a case study of the CFD simulation of propagation of airborne pollutants, in which we investigated spreading of carbon dioxide in a chemical plant. Emitting CO2 was part of the technology and happened 50m above ground level. During the operation of industrial plants machinery sometimes release unwanted substances much closer to the operators handling them. This is the first part of a smoke extraction CFD simulation case study in which I show you how fluid dynamics simul...

During the past 12 years of offering CFD engineering services I had the chance to look into several different types of furnaces. But the most impressive and most terrifying certainly was the sight of a glass melting furnace. We carried out this furnace wall erosion CFD analysis to determine factors that influence degradation of the refractory in contact with molten glass. Looking into the furnace while 10m long flames were roaring above the pool of molten glass I thought hell could look just lik...

I surely said this before but if you are so fortunate to do fluid dynamics simulations as your profession you can always learn something new. Controlled cooling of cylinder head castings after solidification? Sounds cool! Simulation of wall erosion in a glass melting furnace? Exciting! Simulation of 2-phase flow within a Centrifugal Partition Chromatography (CPC) machine and design of a new cell shape? The mother of all simulations, though I never saw such a machine before. And I just guessed ho...

In the previous part I wrote about how effective and flexible meshing had been with SC/Tetra when simulating many extraction head versions for the cylinder head cleaning project. When I wanted to analyse a new extraction head I only had to change and remesh that specific part and attach it to the main mesh again and push GO button. Since the whole simulation domain contained 11 million elements – 6.6 million was the casting alone – this meshing method resulted significant reduction of meshing...

The simulation of metal chip removal with compressed air carried out successfully in 2013 continued in 2014 with new challenges. The results of simulations made in 2013 have been producing profit for the engine manufacturer in every single second of production time since then. In this new phase of the project cleaning performance was further improved. But what kind of new challenges could come after a successfully completed simulation job that led to an optimised cylinder head cleaning process? ...

Sure a Caribbean cruiser is big enough but there are bigger ships in the gas and oil drilling industry. Many of them are tankers but floating refineries are also constructed. I got in touch with one of the latter because of a project and I had the chance to commit a few simulations on a 355m long, 58m wide giant having the daught of a mid sized office block (21 metres). This article can't say a word about the real job, but can introduce you to CFD modelling of waves and floating objects. Before ...

I am definite that the automotive parts cleaning CFD analysis this application example was written about has been the greatest challenge I have faced so far in my professional life as a CFD engineer. It was about the CFD simulation of the cleaning process of cylinder head castings with high pressure air. What is so challenging in that you may ask? Everithing. Let me describe. The situation – of course without names and real life data – is the following. Cylinder head castings go through se...

It was on a hot day in July 2008 when at 10:42pm I got the first message with the subject "Top urgent CFD simulation required". Let me tell you a five day long story of competing against time and a sales person that handled facts rather flexibly. It was many years ago when we were assigned to determine the pressure loss of two seawater suction lines. The flexible hoses were 100 meters long each, they had steel fittings on both ends. Where do you think one needs 100 meter long hoses of which t...

My favourite trick was back at the university when the professor during fluid dynamics lectures (but you can play the same game with maths of structural mechanics) came up with a really-really long and complex equation, then he applied some conditions (saying for example that one or two parameters are neglectable thus not important next to the others) and elegantly crossed out 80% of the equation. From then on it could be solved easily. What should I do if CFD modelling with complex geometry mea...

A couple of years ago I had the chance to work together on a CFD service project with specialists of one of the top fan manufacturing companies in the world. Based on our discussions and running an axial fan CFD modelling benchmark project I made a short summary of the most important guidelines. This gives you a sneak peak into how professionals run CFD simulations of fans for HVAC and automotive applications. 1. Simulation of rotating motion It is not usual to simulate the real rotating moti...

Developers of SC/Tetra, one of the CFD codes we use to solve complex fluid flow and thermal management challenges have gone quite far in terms of human body thermal comfort CFD analysis. This modeling environment is called JOS (Joint System Thermoregulation) and it is designed to provide top-notch human body thermal modeling in environments like a car, bus, an airplane. Furthermore it is just as good as simulating human comfort in built environments as in automotive applications. Development ...

Did you know that thermal management of a cylinder head had started way before it was bolted on your engine block? It was the single most important 90 minutes of its service life. It first happened when the cylinder head casting emerged from the die freshly cast, still liquid behind the thin solid outer layer of aluminium. This article tells how Computational Fluid Dynamics plays a defining part of that first, 90 minute long controlled cooling process. From heat transfer viewpoint we face two...

In 2012 we received an interesting fluid flow and heat transfer simulation job. A silencer had to be installed on a carbon-dioxide exhaust point of a huge chemical factory. Within this project our job was to carry out a CO2 diffusion CFD analysis in the atmosphere of the ammonia works. A chemical factory CFD analysis is complex by its own right but as a bonus how can the area of a whole production facility be modelled? Obviously we had to simplify since the smallest area to look at in terms o...

I had the chance some weeks ago to spend a day at the site of one of our SC/Tetra users. They showed me a small mixer in their lab on which they make some demonstrations and test measurements for their students. They also created a CFD simulation to model the mixing process. And because it was so interesting, I decided to build a free fluid surface CFD simulation with an other mixer geometry. The aim was just to play with it a little bit and to show what interesting features such a mixer had. La...

This information video shows CFD modelling of an interesting physical phenomenon. Pressure wave CFD simulation is used on a test pipe to demonstrate wave propagation in pipes. This phenomenon is also called the water hammer effect. There are two examples shown in the video. The first is a simple pipe, the second one is a bit more complex because there are junctions in the pipeline. Pipe geometry has important effect on the pressure wave and from the video below you will see why. This phenomen...

The world's first and still existing roundhouse was the home of engineering simulation for two days on 15th - 16th April 2015 in Derby, UK, where in cooperation with CRADLE Europe Flow Computing Technologies manned one of the stands. I would like to highlight two interesting things from the massive load of engineering simulation stuff. The first is that several companies exhibited impressive applications of virtual reality. At one for the stands a student just checked the virtual cockpit o...

What is the majority of development efforts in automotive industry about? Besides making a car a communication centre and internet café rather than source of enjoyment, since mobile phones are developed faster than car dashboards everything is about being green. Luckily there are still some exceptions.  This is what we experienced in Birmingham at the Advanced Engineering UK at the end of 2013. The problem of being greener can be managed on many different ways. Starting from the truly fantast...