What is the effect of over vacuum in a steam turbine and a low vacuum in a condensing turbine?

What is the effect of over vacuum in a steam turbine and a low vacuum in a condensing turbine?

The maximum ∆P created by lowering the vacuum. Vacuum pump maintaining vacuum in steam condenser and as vacuum increases steam pressure at exit of turbine is low so results into fasten the condensation process.

What is vacuum pulling in steam turbine?

The condenser pulls a vacuum throughout the steam system if main steam throttling valves are left open. Superheated steam produced at low temperature may be used to warm the turbine while boiler temperature and pressure increases. As the temperature increases and pressure drops, the steam becomes more superheated.

How vacuum is created in turbine?

After the steam leaves the exhaust section, it enters a condenser, where it is cooled to a liquid state. The process of condensing the steam usually creates a vacuum, which then brings in more steam from the steam turbine. The water is returned to the steam generation system, reheated and reused.

What happens when a condenser loses its vacuum?

A common cause of poor condenser vacuum is excessive air ingress or leakage. Any fall in condenser vacuum would have consequent rise in turbine heat rate vis-à-vis plant heat rate. As a result, cost of power generation would increase with eventual loss in revenue earning.

What is the effect of high vacuum in turbine?

Re: Effect in steam turbine due to high vaccume in condensor Increasing the pressure in the condenser reduces the pressure across the turbine, which will reduce its output.

What is vacuum pressure?

Vacuum pressure is measured relative to ambient atmospheric pressure. It is referred to as pounds per square inch (vacuum) or PSIV. The electrical output of a vacuum pressure transducer is 0 VDC at 0 PSIV (14.7 PSIA) and full scale output (typically 5 VDC) at full scale vacuum, 14.7 (0 PSIA).

What are the reason for low vacuum?

Low vacuum can be caused by low compression, intake leak or tight valves. The gauge needle bounces around a lot-uneven compression if the vacuum reading fluctuates within the normal range.

What is vacuum efficiency?

It is defined as the ratio of actual vacuum in condenser as recorded by the vacuum gauge to the ideal vacuum. In that case total pressure in condenser will approach ideal pressure. Vacuum efficiency is also defined as the ratio of the partial pressure of steam to the measured condenser pressure.

How do vacuums work physics?

Vacuum cleaners work because of Bernoulli’s Principle, which states that as the speed of air increases, the pressure decreases. Air will always flow from a high-pressure area to a low-pressure area, to try to balance out the pressure.

Why is vacuum important in steam turbine system?

The importance of the vacuum being maintained in the steam condenser: 1. By maintaining a vacuum in the steam condenser, the efficiency of the steam-power plant can be increased as greater the vacuum in the system, greater will be the enthalpy drop of steam. Therefore, more work will be available per kg of steam condensing.

Why do you need a vacuum in a steam condenser?

By maintaining a vacuum in the steam condenser, the efficiency of the steam-power plant can be increased as greater the vacuum in the system, greater will be the enthalpy drop of steam. Therefore, more work will be available per kg of steam condensing.

Why does steam from a turbine cause condensate?

Steam blowing from a turbine gland also creates condensate, causing undue moisture in plant equipment. When vacuum lost suddenly from running condenser, shut down immediately. The condenser cannot stand the steam pressure, the condenser tubes may leak from excessive temperature.

Why is a partial vacuum maintained in a condenser?

In other words, the specific volume of water at a given pressure is many times lower than that of steam. This enormous reduction in volume creates the vacuum inside the condenser. This partial vacuum will draw in more gas to be cooled.