1) My previous answer was regarding the effect of cavitation and column collapse in a frictionless system in Bentley HAMMER. I can confirm that it does not introduce energy loss.
2) This again is a theoretical question beyond the scope of Bentley products, but I will try to answer. Although a pipe may change directions such as a 90 degree bend, we know that this certainly does not cause a transient in itself. HAMMER can analyze transient forces at end points so the force from such a change in pipe direction can be quantified.
3) HAMMER's Sample1 model is a good example of wave reflection. "Res" is a reservoir and "Val" is a valve that closes and stays closed (acts as a dead end).
Regards,
Jesse DringoliTechnical Support Manager, OpenFlowsBentley Communities Site AdministratorBentley Systems, Inc.