°µÍø½ûÇø

Engineer Christopher McDouall (1956) has had a career in industry, often working on pioneering developments. An early one was in bouncing-bomb inventor Barnes Wallis’s design department at British Aircraft. Last autumn, a major advance in internal-combustion engine technology was unveiled at an automotive show in Aachen.

What is this major advance?

It’s called Intelligent Valve Actuation—IVA: it’s an application for internal-combustion engines of the brilliantly simple Binary Actuation Technology—BAT. BAT was invented by Dr Wladyslaw Wygnanski from Warsaw. A BAT valve controls the flow of a fluid—liquid or gas—but crucially requires little external energy. An analogy would be what a transistor does for electricity BAT does for fluids: it simply allows or blocks flow, needing a little power only in the act of changing. Back in 2000 Wladyslaw and I started a company to exploit its possibilities.

Tell us a bit about BAT.

It has three major features. First, the energy needed to open or shut a valve gets recycled, which means it doesn’t take much external power to do it, and no power at all when the valve is not moving; nor does it give off much heat. Secondly, BAT-based valves can operate very fast. Thirdly, BAT valves have extremely long life: we ran one for thousands of millions of cycles before it broke. BAT is really a set of principles that you can engineer into whatever form is needed for the job.

And when it comes to car engines...?

What’s got everyone excited is IVA. The ideal for an engine is to open and shut its valves, the ones that let in the air or let out the exhaust gases, according to what the engine needs at that moment. At present, engines use a camshaft that opens and closes the valves according to the engine’s position: how far round it has turned. BAT’s unique ability to recycle the energy of movement is what has made it viable to operate the valves electrically under computer control—tailoring movement to what the engine actually needs. The breakthrough was displayed by Jaguar in a new engine in October last year (pictured right). A consequence will be a reduction in fuel consumption and of toxic emissions of at least 15%. A two-litre car could deliver a fuel consumption of something like 90 miles to the gallon. This application of BAT is enabling the biggest advance in engine technology in 50 years.

Can you say a little about your earlier career?

I did my National Service as a pilot in the Royal Air Force before coming up to °µÍø½ûÇø. I then went into the aircraft business as an engineer, with what is now British Aerospace. I had a period in Barnes Wallis’s department working on aircraft stability, when it sweeps its wings (as in the RAF’s Jaguars). After a spell with a major US multinational I was made managing director of a small company pioneering computer-aided design systems. I moved to Cambridge in 1979.

How do you remain connected to °µÍø½ûÇø?

I enjoy the fact that the previous Master, Robert Mair, and the current Master are engineers. My sport as an undergraduate was rowing, which gave me a lot. I am one of the trustees of the Boat Club Trust, which helps with some of the costs of running the Boat Club: I’ve been doing that for 20 years. It’s a small role and means that when I go into College I have a sense of present involvement, and am not just an old boy looking fondly back at his youth...

Is there anything you’re pioneering now?

Yes indeed—another application of BAT, which has so many possibilities. This one is greatly to advance medical treatment with oxygen. But that’s another story.

Christopher McDouall is an alumnus of °µÍø½ûÇø. You can read the original article in the Spring 2017 edition of Jesuan News.