Maybe translating it to english gives a higher succes rate
Janko is right but I decided to copy&pasted your French text in Google Translate and here is my answers:
1.Precise answer about what the arrows mean can not be given with the picture taken out of the content of the presentation but most probably it shows that all 6 boundary of this CFD Model are open for exchange of flow (heat). Because all the arrow are pointing inward that is either wrong over infinite time or they are correct for certain period of time (for flow only if the air is considered compressive fluid).
2. There are Flow Simulation Manuals ( solvingengineeringproblems.pdf and technicalreference.pdf), as well a Tutorial. Please request those from your SW Provider. You can also click on the "?" icon which is displayed in the right upper corner of each Flow Simulation panel for detailed explanation how to use the panel, as well as with definitions of the parameters and variables involved.
Hope this help.