How is the flow rate from an in-line axial piston pump increased?

Increasing the flow rate from an in-line axial piston pump is achieved effectively by increasing the swash plate angle. The swash plate in an axial piston pump tilts at an angle, allowing the pistons to move in and out of their cylinders. As the angle of the swash plate increases, it allows for a greater displacement of fluid with each piston stroke, subsequently increasing the overall flow rate of the pump.

The relationship between the swash plate angle and flow rate is crucial because the swash plate's angle directly affects the volume of fluid displaced per revolution of the pump. A larger angle typically leads to a higher volume of fluid being pushed through the system, which is why this approach is commonly utilized in hydraulic systems to boost performance.

In the context of the other options, decreasing the swash plate angle would reduce the displacement and therefore decrease the flow rate. Increasing fluid temperature or reducing fluid viscosity can potentially affect pump performance, but they do not have as direct an impact on flow rate as adjusting the swash plate angle does. Altering fluid temperature and viscosity can improve fluid dynamics, but they are secondary factors compared to the mechanical adjustments achievable through the swash plate. Thus, increasing the swash plate angle is the most effective and direct method