With Heathrow handling approximately 67 million passengers a year to 186 destinations in 90 countries, getting people through the doors is the first test of efficiency for one of the world’s top airports. Yet this also means that doors have to constantly open and close, 24 hours a day, 365 days a year. At Terminal Three this led to reports of discomfort from draughts for the check-in staff of the long haul carriers who use this terminal as well as for passengers waiting to check in.

The most obvious solution – a major rebuild of the entrance door configuration – was also the most expensive option and the most likely to disrupt passengers and staff during rebuilding. So it was Biddle Air Curtains who came up with the technology which would provide the lowest-cost, high-efficiency route to a comfortable, draught-free environment for staff and passengers alike.

Using pioneering Computational Fluid Dynamics (CFD) software developed jointly with Warwick University, Biddle was able to provide detailed air movement modelling of the Terminal Three Departures area and demonstrate that the problem could be solved without any expensive structural changes to the doors or entrance façade.

Biddle’s Adrian Higginson said: “We discovered that with a new installation of our CA door curtains located over the lobby and inner doors, we could not only solve a potentially disruptive situation but do so in a very cost-effective way without major building work.”

The Biddle CA range which was used for the Heathrow solution differs from conventional air curtains because it uses patented air rectifier systems to provide constant air velocity – effectively providing an invisible barrier from ceiling to floor which prevents ingress of cold air as well as loss of the internal conditioned air.

The CFD modelling process is used at the commencement of a project to plot the design, layout and heat and mass transfer of any given work area. It produces results which include the optimum position, discharge velocity and performance specification for an air curtain installation. Combined with the high performance of the CA Invisidor air curtain, Biddle was able to resolve the draught issues at Heathrow without the need for high-cost capital works.

Biddle also claims that the CA technology offers the most energy efficient solution in open door situations from shops to airports. “At a time when oil prices are at an all time high, building operators have to take steps to minimise heating energy costs. By effectively providing a heat loss barrier at constantly opening doors, Biddle’s CA range offers fast payback and ongoing economies to specifiers,” said Adrian Higginson.

Since this project was completed, the advantages gained from the departures area installation have been taken up by the installation of Biddle CA air curtains in the Terminal Three Arrivals Extension where major development work is linked to plans to accommodate the world’s largest ever commercial aircraft, the Airbus A380. In addition to the £100 million development of a new pier at Terminal Three for this aircraft, the Arrivals entrance/exit doors are using Biddle air curtains to provide the most comfortable environment for the large throughput of passengers expected as the A380 becomes the first aircraft capable of discharging a total of 555 upper and lower level passengers at the same time.