17 March, 2010

# Commercial CFD Starts Here …

Posted by

The global commercial CFD industry can trace its origins to a small terraced shop in New Malden, a south-westerly suburb of London. It may sound like the birth of a retail empire, rather than a CAE business – but its pretty much true. Let me fill in some details.

8 February, 2010

# “Sledgehammer CFD” – The Best Approach?

Posted by

Re-reading my last blog (Beginning at the Beginning …5 Parabolic or Elliptic, Or Somewhere In Between?) a slightly disturbing thought occurred to me. Does the distinction, highlighted in that blog, between parabolic, partially-parabolic, and elliptic solution methods have any real relevance to present day CFD?
6 January, 2010

# Beginning at the Beginning … 5 Parabolic or Elliptic? – Or Somewhere In Between?

Posted by

To complete my recollections of the time when I was working on my PhD at Imperial College during 1969-1972 …

First of all, a short theoretical interlude. As CFD theorists know, it is often useful to categorise classes of flow according to the form of the governing equations – as parabolic, hyperbolic, or elliptic. Leaving aside hyperbolic – supersonic – flows – I want to focus on the distinction between parabolic or elliptic flows as applied to low-speed subsonic flows.
21 August, 2009

# Beginning at the Beginning …3 Improving SIMPLE

Posted by

In my last blog I explained how Suhas Patankar created the SIMPLE algorithm in 1970, and how the 3D Boundary Layer Group at Imperial College then adopted SIMPLE for all its future work.

I first applied SIMPLE to the problem that I had been working on with the SIVA method – laminar flow in the inlet region of a rectangular- (mainly square-) sectioned duct. This led me to identify some deficiencies in SIMPLE in its standard form, and to devise an improved formulation.
13 August, 2009

# Beginning at the Beginning … 2

Posted by

In the first blog in this series I described how the research group at Imperial College, under Professor Spalding, on computational methods for 3D parabolic boundary-layer flows (the “3D Boundary Layer Group”) got started, with me as a relatively junior member. I described how I (re)discovered the need to use a staggered grid when solving for the primitive variables, (pressure and velocities) – and how Suhas Patankar joined the group around mid 1970.

To continue …
29 July, 2009

# Beginning at the Beginning … 1

Posted by

In my first blog I promised reflections based on my 40 years in CFD. How best to start?

What was the advice that the King of Hearts gave to the White Rabbit? – “Begin at the beginning, go on to the end, and then stop.” While not specifically intended in the context of blogs – it seems like good advice to me. So – starting at the beginning …

15 July, 2009

# 40 Years is a Long Time in CFD!

Posted by

Talk about being in the right place at the right time …..!

Forty years ago this year, in the autumn of 1969, I embarked on my PhD on “Convection Processes in Three Dimensional Boundary Layers” in Professor Spalding’s Heat Transfer Section in the Mech Eng Department at Imperial College, London. This meant that I was a member (albeit a rather junior member) of a research team developing new computational methods for 3D parabolic boundary-layer flows.

It was clear even then that what we were involved in was something big and exciting – the creation of what was possibly the first practical 3D Navier-Stokes computational method anywhere. As part of this work, Suhas Patanker came up with the SIMPLE algorithm. What with this and associated work on turbulence modelling going on at the same time (leading, among other things, to the two-equation k-epsilon model in the basic form that we know it today), I don’t think that it’s too much to claim that much of the foundations of present day CFD (the name was coined later) were laid at Imperial College 40 years or so ago. It was great to be part of it. As I said – talk about being in the right place at the right time! Read the rest of this entry »