Test The Limits

The Automobile Micro-Climate

By Exa

July 07 2015

It’s July, and getting hotter every day. Spending time in the car can provide a welcome respite from the soaring temperatures outside. That said, a car’s heating, ventilation and air conditioning (HVAC) should be unobtrusive. The ultimate cabin comfort system is one you don’t know is there. You don’t even need fiddle with it. But that’s extremely hard to achieve which is why clients turn to us to simulate condenser cooling and cabin airflow.


Vents are always contentious. No one likes them. Designers in particular would love to get rid of them, and Jaguar has almost managed that in the XF where they almost hide themselves when not needed.


But customers want to be comfortable and that means they want to feel air on their face, if only for a short time. You could put the vents in the A-pillars, but everyone’s fighting for that space. It’s a problem we’re working on – and have covered in this blog previously.


Air conditioning in the summer months is replaced by heating in the winter. But feeling warm in those times is not enough. Demist and defrost of the windshields are critical for safety and therefore heavily regulated. At PowerFLOW, we customarily simulate airflow over the windscreen for our clients. Uniform distribution of the airflow on the windshield surface makes all the difference for quick demist and defrost. Sometimes this requires the change of ducts and registers.


Sometimes carryover parts might not work on the car you’re currently producing. That was the case for neck warmers for one maker which was looking to produce a new convertible.


This system was designed to pipe warm air from the headrest to make driving with the roof down more comfortable.


However we discovered the system our client was about to use actually didn’t direct air to the neck but was jetting it out over their head. The shape of the head rest meant the air was being dragged along the surface.


We discovered this in simulation. By virtually reshaping the air duct we could redirect the flow where it was needed. The finished design met the customer’s expectations of what a neck warmer should achieve – you guessed it, a warm neck! Just not in July.


Another issue vehicle manufacturers face with the HVAC ducts is noise. Who hasn’t turned down the air conditioning to better hear the music coming from the car Hi-Fi system? This will be the topic of one of our future blogs.