What happens differential pressure between oil and hydrogen increases
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The need for hydrogen
Central power stations have been producing electric power and supplying it to a customer base since the early 1880s. As the demand for power increased, so did the physical size of air cooled electric generators — more megawatts required more iron. In the early 1930s, it became apparent that a better method of cooling these large turbo generators was required and the first hydrogen cooled generator was introduced.
Hydrogen replaced air as a cooling agent principally because of its low density and superior cooling properties. Hydrogen is the lightest known gas and has the lowest density of any stable gas. Because hydrogen is one quarter the density of air, wind resistant losses are greatly reduced and efficiencies are gained. Hydrogen also has a thermal conductivity of nearly 7x that of air, resulting in much better heat transfer through forced convention. (Table 1)
Using hydrogen as a cooling medium has additional benefits. Because the generator case is a sealed pressure vessel, the internal components are less likely to be affected by outside contaminants. Also, pressurized hydrogen will suppress partial discharge and increase the amount of voltage required to cause a component breakdown.
When used properly, hydrogen is 14x more efficient than air in removing heat and greatly reduces windage friction losses. However, a mixture of hydrogen in air of between 5 percent and 75 percent becomes very explosive. Also, the generator efficiency is reduced as the purity of the hydrogen drops. To ensure safe and efficient operation of the generator, the hydrogen purity should be maintained above 97 percent.
Hope this helps you
Central power stations have been producing electric power and supplying it to a customer base since the early 1880s. As the demand for power increased, so did the physical size of air cooled electric generators — more megawatts required more iron. In the early 1930s, it became apparent that a better method of cooling these large turbo generators was required and the first hydrogen cooled generator was introduced.
Hydrogen replaced air as a cooling agent principally because of its low density and superior cooling properties. Hydrogen is the lightest known gas and has the lowest density of any stable gas. Because hydrogen is one quarter the density of air, wind resistant losses are greatly reduced and efficiencies are gained. Hydrogen also has a thermal conductivity of nearly 7x that of air, resulting in much better heat transfer through forced convention. (Table 1)
Using hydrogen as a cooling medium has additional benefits. Because the generator case is a sealed pressure vessel, the internal components are less likely to be affected by outside contaminants. Also, pressurized hydrogen will suppress partial discharge and increase the amount of voltage required to cause a component breakdown.
When used properly, hydrogen is 14x more efficient than air in removing heat and greatly reduces windage friction losses. However, a mixture of hydrogen in air of between 5 percent and 75 percent becomes very explosive. Also, the generator efficiency is reduced as the purity of the hydrogen drops. To ensure safe and efficient operation of the generator, the hydrogen purity should be maintained above 97 percent.
Hope this helps you
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