Turbomachine Casing Component with Dynamic Diameter Adjustment

The patent applies the dynamics principle by making the inner casing movable rather than fixed, allowing it to dynamically adjust its position radially in response to changing operating conditions. The inner casing moves closer to the outer casing during high-speed operation to reduce clearance and minimize air loss, while maintaining sufficient clearance during re-slam maneuvers to avoid blade tip contact. This dynamic adjustment resolves the contradiction between reliability and energy loss by adapting the clearance to actual operational needs.

The patent changes the physical parameter of casing diameter by introducing an actuation means that can alter the inner casing's radial position. This parameter change allows the system to optimize the blade tip clearance based on operating conditions - reducing clearance during high-speed operation to improve efficiency while maintaining adequate clearance during transient maneuvers to ensure reliability. The actuation means enables continuous adjustment of the critical clearance parameter.

The patent transitions from a static fixed clearance design to a dynamic adjustable clearance system. The movable inner casing with actuation means allows the clearance to be optimized during operation rather than being fixed during manufacturing. This resolves the contradiction by enabling the system to achieve both manufacturing simplicity (through a relatively straightforward movable casing design) and high efficiency (through operational optimization of clearance based on actual operating conditions).

The actuation means is designed to be driven by the operational parameters themselves (rotational speed and pressure differential), allowing the system to self-adjust the clearance without external control systems. This self-service mechanism maintains manufacturing precision while improving efficiency, as the clearance automatically optimizes based on real-time operating conditions rather than requiring complex external control systems.

The patent addresses thermal expansion complexity by incorporating a dynamic adjustment mechanism that can compensate for dimensional changes. The movable inner casing with actuation means can adjust its radial position to maintain optimal clearance despite thermal expansion of the outer casing or drum. This dynamic approach handles the complexity of thermal expansion accommodation more effectively than fixed clearance designs, as it can adapt to varying thermal conditions during operation.

The actuation means enables continuous adjustment of the inner casing position to compensate for thermal expansion effects. By changing the radial parameter of the inner casing based on operating conditions, the system can maintain reliable clearance despite thermal dimensional changes. This parameter adjustment capability handles the complexity of thermal expansion accommodation more effectively than static designs.

The actuation means is designed to be self-driven by the operational parameters (rotational speed and pressure differential), eliminating the need for external control systems. The pressure differential across the inner casing and the rotational speed of the drum directly drive the adjustment mechanism, allowing the system to self-optimize clearance without adding complex external control systems. This self-service approach improves efficiency while minimizing the increase in device complexity.

The patent utilizes pressure differential (pneumatic principle) to drive the actuation means. The pressure difference between the high-pressure side and low-pressure side of the inner casing provides the force needed to move the casing radially, adjusting the clearance automatically. This pneumatic actuation mechanism achieves the desired efficiency improvement while keeping the added complexity relatively low, as it leverages the existing pressure differential in the turbomachine system rather than requiring separate actuation systems.