1. Expansive Working Fluid: Steam engines utilize steam, which is an expansive working fluid. As the steam enters the cylinder, it rapidly expands, exerting significant force on the piston from the beginning of the stroke. This inherent property of steam contributes to the high starting torque of steam engines.
2. Large Pressure Difference: The pressure difference between the boiler and the cylinder is usually significant in steam engines. This pressure difference creates a high force acting on the piston, resulting in substantial starting torque.
3. Mechanical Advantage of Piston and Crank Mechanism: The piston and crank mechanism in steam engines provides mechanical advantage, amplifying the force generated by steam pressure into torque. The conversion of linear motion (piston movement) into rotary motion (crank rotation) enables the effective transmission of power to the output shaft.
4. Controlled Steam Admission: In steam engines, the admission of steam into the cylinder is carefully controlled by valves. This allows for precise timing and duration of steam flow, ensuring that the maximum pressure and force are applied during the initial phase of the stroke, thereby enhancing starting torque.
It's important to note that the high starting torque of steam engines was particularly advantageous during the early industrial era, especially for applications such as locomotives, marine engines, and heavy machinery, where the ability to overcome high initial loads was crucial.
