For this use, I would choose
besides. You are not excluding blade profile loss as important--you are writing about other losses. Another option would be
Also, I'd correct the bolded parts as well for plurality agreement, independent clauses, and article usage. Not knowing your domain, I am unsure of styles particular to it, but some of the structure was a bit confusing:
As discussed previously, there is another kind of loss in the Wells turbine besides loss due to blade profile. These losses are secondary flows. Figure 11 highlights the main secondary flow structures in Wells turbines such as a tip leakage vortex and horse-shoe vortices near the hub (endwall boundary layer flow).
It is also common to reorder the sentence to use
other than, but I prefer the above.
As discussed previously, other than loss due to blade profile, there is another kind of loss in the Wells turbine.
Or you might want to simplify by dropping unnecessary parts, making it more terse and introducing the main point (secondary flows) in the first sentence:
Besides loss due to blade profile, the Wells turbine has losses due to secondary flows.