【Mechanical Equipment Technology Exchange Edition】Mechanical Equipment 【Daily Question】20191107
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Question: What is fan loss? There are no answers provided for this series of posts; fellow netizens are free to share their own opinions – just reply with what you understand. Replies earn rewards ranging from 5 to 15 points; all forum members are welcome to participate actively and support the development of the forum! ! ! Recently, the factory spent another week carrying out emergency repairs to replace the actuators of the Akka valves in Xuzhou; however, the new actuators could not be installed, so the old ones were put back in place. Worked a whole day on chemical equipment and machinery
Was there a problem with the initial review of the drawings? Did the manufacturer not provide any technical specifications?
Due to the annular arrangement of the blades along the rim, the flow passage cross-section takes on a fan shape. The pitch and circumferential velocity vary at different heights along the blade, causing the inlet angle of the steam flow to differ from the blade’s inlet angle along the blade height, which results in impact losses. Furthermore, the airfoil profiles on various sections along the blade height of equal-cross-section blades cannot maintain radial balance of the steam flow in the moving and stationary blade gaps, resulting in a radial flow of the steam flow and causing additional losses; these losses constitute fan losses.
Due to the annular arrangement of the blades along the rim, the flow channel cross-section takes on a fan shape. The pitch and circumferential velocity vary at different heights along the blade, resulting in the inlet angle of the steam flow varying with the blade height and thus causing impact losses.
Fan-shaped loss refers to the phenomenon where, due to the radial arrangement of the blades around the rim, the flow passage cross-section takes on a fan shape. As a result, the pitch, circumferential velocity, and inlet angle vary throughout the height of the blade, which causes the steam flow to strike the blades and result in energy loss. Additionally, the steam flow generates radial movements that further consume its energy.
Fan-shaped loss refers to the phenomenon where, due to the radial arrangement of the blades around the rim, the flow passage cross-section takes on a fan shape. As a result, the pitch, circumferential velocity, and inlet angle vary throughout the height of the blade, which causes the steam flow to strike the blades and result in energy loss. Additionally, the steam flow generates radial movements that further consume its energy.
Fan loss: The turbine blades are mounted on the outer circumference of the impeller, forming an annular blade row. When the blade is a straight blade, its channel cross-section varies along the blade height, with the variation increasing as the blade gets taller. Furthermore, due to the centrifugal effect of the tangential velocity of the steam flow at the nozzle exit, the steam flow is pushed toward the top of the cascade, causing the steam pressure at the nozzle exit to increase gradually as one moves upward along the cascade height. When designing based on the theory of one-dimensional flow, the selection of all parameters ensures that the value at the average diameter section is optimal; however, for the parameters at other sections along the blade height, deviations from this optimal value result in additional losses, which are collectively referred to as fan losses
Since the blades are arranged in a circular pattern along the rim, the flow passage cross-section takes on a fan shape; the pitch and circumferential velocity vary at different heights along the blade, resulting in the steam inlet angle varying along the blade height and not being equal to the blade’s inlet angle.
Fan-shaped loss refers to the phenomenon where, due to the radial arrangement of the blades around the rim, the flow passage cross-section takes on a fan shape. As a result, the pitch, circumferential velocity, and inlet angle vary throughout the height of the blade, which causes the steam flow to strike the blades and result in energy loss. Additionally, the steam flow generates radial movements that further consume its energy.
Due to the annular arrangement of the blades along the rim, the flow passage cross-section takes on a fan shape. The pitch and circumferential velocity vary at different heights along the blade, causing the inlet angle of the steam flow to differ from the blade’s inlet angle along the blade height, which results in impact losses. Furthermore, the airfoil profiles on various sections along the blade height of equal-cross-section blades cannot maintain radial balance of the steam flow in the moving and stationary blade gaps, resulting in a radial flow of the steam flow and causing additional losses; these losses constitute fan losses.
The turbine cascade is installed on the outer circumference of the impeller and is an annular cascade. When the blade is a straight blade, its channel cross-section varies along the blade height, with the variation increasing as the blade gets taller. Furthermore, due to the centrifugal effect of the tangential velocity of the steam flow at the nozzle exit, the steam flow is pushed toward the top of the cascade, causing the steam pressure at the nozzle exit to increase gradually as one moves upward along the cascade height. When designed using the single-flow theory, the selection of all parameters ensures that the value at the average diameter section is optimal; however, for other sections along the blade height, deviations from this optimal value result in additional losses, which are collectively referred to as fan losses.