Aerodynamics is a factor which is related to the air resistance of a vehicle. Aerodynamics is used in the vehicle to reduce the fuel consumption. There have been many models in the market which were very chic in design but aerodynamically they failed.

The companies had to change the shape of the vehicle altogether but in the end the result was a very out shaped vehicle with less aerodynamic improvement. 

To design aerodynamically fit vans it needs a lot of research. Companies have to do extensive R&D when decide to launch a new design. A lot of public research is conducted to get the demand of the people. And then according to the demand design is prepared as the design of Citroen dispatch was made. 

The shape of the car should be made appropriate to reduce the air resistance during design phase. This is very important. If the design is 100% perfect than the car can assure you the highest profits. Once the design is passed and the van is manufactures, its design after manufacturing is very hard to change. That is why the vans with inadequate R&D for aerodynamics fail in the market. 

Another issue is that the large vans consume fuel too much and excrete the same amount. This is increases the air pollution. Scientists dislike such vans and they propose the public to buy vans which are fit for nature. They discourage those models which are not aerodynamically good. Citroen relay has been the popular choice for such sci8entists and environmentalists. 

There is a template for a good van design. This template suggests that a van must have fairings, a rounded front for aerodynamics and rounded back side. Citroen Dispatch, which was manufactured using this template, has been very successful in the market.