Tech Bite: Spanish GP technical image gallery

The Spanish Grand Prix marks the return to Europe following four flyaway races, and is therefore dubbed the 'upgrade race' as teams often wait until this weekend to debut large developments.

We've compiled a gallery of upgrades below with brief comments by Grand Prix Times technical contributor Matthew Somerfield.

Williams FW37 during build up exposes some of the power unit details but also shows us that the team have added two vortex generators to the leading upper edge of the sidepod (marked in yellow)

Williams FW37 rear brake duct detail, note the crossover pipe (marked in yellow) which is used to cool the brake calipers.

McLaren MP4-30 nice detail shot of the front-brake during build up, note the blown axle (marked in red) which takes air from the duct and dispatches it outside the wheel, which in-turn helps to deal with the wake shed by the front wheel.

Ferrari SF15-T detail shot of the new front brake duct, a small fin has been added to the inboard section of the duct (marked in yellow), whilst the crossover duct (marked in blue) has also seen revision, this duct sends airflow collected by the main air scoop and pushes it out through the wheel face, helping to deal with the wake shed by the front wheel.

Mercedes W06 - Great shot of the car exposed during build, note the small fins on the side of the monocoque (marked in yellow) which sit in behind the bargeboard and help to condition flow around the sidepods undercut.

Sauber C33 - A new leading edge slat has been added by the team, mounted between the inside vortex generator and cockpit, its job is to increase the operating window of the sidepod, delaying seperation downstream.

McLaren MP4-30 a great shot across the garage capturing the ever elusive Honda RA615-H power unit.

McLaren MP4-30 nice detail shot of the teams front wing.

Mercedes W06 nice detail shot of the car during build up shows the splitter and front brake ducts inner detail.

Ferrari SF15-T laid bare, shows the innovative radiator configuration being used by the Scuderia for 2015.

Force India VJM08 front wing detail.

Lotus E23 front wing detail.

Lotus E23 detail shot shows the exposed intercooler arrangement in the left hand sidepod.

Lotus E23 detail shot shows the exposed radiator arrangement in the right hand sidepod.

Ferrari have added some small winglets ahead of the diffuser in Spain. Attached to the gurney support these winglets will change how the outer portion of the diffuser operates.

Ferrari have increased the number of slots in the floor ahead of the rear tyre, these are used to control how the airflow spilt from the tyre as it deforms impinges on the diffusers performance.

In the crease of the sidepod Ferrari have mounted a small canard (marked in yellow), which will create a pressure gradient, increasing performance as the air flows into the coke bottle region.

Ferrari have changed their bargeboards on the SF15-T for Spain (marked in yellow) adding two slots which bleed pressure from one side of the element to the other, increasing the parts operating window.

Lotus E23, detail shot of the slotted bargeboard.

Red Bull have elongated the lower 'tongue' section of the 'S' duct readying the car for the deployment of the teams new shorter nose.

Red Bull's new shorter nose has finally made its way to the car having reportedly taken 4 attempts to pass the crash tests.

Ferrari SF15-T with flo-viz applied to the rear-wing.

McLaren MP4-30 front brake duct detail, note how the tear drop shaped outlets allow hot air to escape into the wheel.

Williams FW37 front brake duct detail, note how the cake tin is designed with a countersunk outlet to allow hot air from the disc to escape out through the face of the wheel.

Images supplied by and copyright Octane Photographic | Commentary by Matthew Somerfield (@SomersF1)