Questions about extraction condensing steam turbine

An extraction condensing steam turbine without extraction steam is equivalent to a pure condensing steam turbine, and its overall efficiency decreases.； When an extraction condensing steam turbine is used to extract steam, the larger the extraction steam volume, the higher its thermal efficiency.

I don’t understand, but I can learn from it* study *

After the pumping is put in, the flow rate increases and the power also increases.

The total power should remain unchanged after putting in the extraction steam. It can be used in pure condensation condition without putting in the extraction steam. This requires adjusting the extraction steam amount according to the requirements of the thermal user.；

Ask your fat black supervisor, haha, Ning Mei’s friend.

It shouldn't have much impact on the efficiency of the extraction steam turbine, right?； Is it designed based on the intended users?~

Because the steam turbine is a comb seal, it cannot achieve 0 leakage 1: Steam extraction is to prevent high-temperature steam from leaking into the atmosphere 2: Prevent air from entering the body to pollute the steam and affect the operation of the unit

Haha, 8th floor! That's the vacuum pumping system of the steam turbine! It is two different concepts from the extraction steam heating system!

The concept is wrong. If the air extractor is not installed, the vacuum degree of the condenser cannot be reached, and the steam turbine will interlock to protect itself. In other words, the condenser cannot operate normally.

On the 8th and 10th floors, ~~~~~~~~~~~~~~~~~~~Under the same output power, the amount of steam entering the steam turbine must be larger than that without pumping. Therefore, the impulse impact and force on the unit will increase. Therefore, the most obvious thing is that the axial force of the turbine will increase, and the vibration and bearing temperature will rise accordingly. However, the degree of vacuum can also be considered as the exhaust pressure. It becomes better with the increase in the amount of pumping, but If the pumping is continued after reaching a certain level, the drum effect of the final blades of the low-pressure cylinder will easily occur at high speeds. Because under the premise of matching the power, the increase in the pumping volume will inevitably reduce the condensation volume. That is, the turbine speed will increase faster than the steam flow rate entering the low-pressure cylinder through decompression and expansion of the stator blades. In this case, the turbine will do work on the steam, and the exhaust temperature will rise, and the exhaust pressure will also rise. Because there are usually corresponding matching problems between air extraction volume and condensation volume, the manufacturer should give the optimal condensation/extraction volume ratio during design.