From HUST (Huazhong University of Science and Technology) to Tianhe Airport

You must refer to the campus located at No. 1037 Luoyu Road, right?
If so, there is no direct way to the airport from the campus, and you need to transfer.
You can take the bus No. 703 or 510 from Luoyu Road to Fujiapo Bus Station (CNY2) (by taxi, it costs CNY25 or a little more), and then take the shuttle bus to airport directly (CNY32).

If you take a taxi, and the fare is about CNY130.