B) 1, 3 and 4 only

Water hammer is a phenomenon that occurs when there is a sudden change in the velocity of flowing water in a pipeline or conduit. This change in velocity results in a pressure surge that can cause damage to the system. Certain devices in hydraulic systems are more likely to experience water hammer, and in this case, the devices concerned with water hammer are the hydraulic ram, penstock, and draft tube.

1. Hydraulic ram:
A hydraulic ram is a device that uses the energy of flowing water to pump water to a higher elevation. It operates by utilizing the momentum of a moving column of water to create a pressure differential that drives the water upwards. When the flow of water is suddenly stopped or slowed down, such as when a valve is closed, water hammer can occur due to the rapid change in flow velocity. This can lead to pressure surges that can damage the hydraulic ram and the associated piping.

3. Penstock:
A penstock is a large pipe or conduit that controls the flow of water in a hydroelectric power plant. It is used to direct water from a reservoir to the turbines. Due to the large flow rates and high velocities involved in hydroelectric power generation, the sudden closure or opening of a penstock valve can result in water hammer. The pressure surges caused by water hammer can lead to damage to the penstock and other components of the power plant.

4. Draft tube:
A draft tube is a component of a hydroelectric turbine that is used to direct the flow of water leaving the turbine. It helps to reduce the pressure of the water and increase the efficiency of the turbine. The abrupt closure of a draft tube valve can cause water hammer due to the sudden change in flow velocity. This can result in pressure surges that can damage the draft tube and the turbine.

In summary, the hydraulic ram, penstock, and draft tube are devices that are likely to be concerned with water hammer phenomenon in their design and operation. It is important to take into consideration the potential for water hammer when designing and operating these devices to prevent damage and ensure the safe and efficient operation of the hydraulic systems.

Correct Answer: 1, 3 and 4 only