IGT PO1.2

Which is ideal cycle used for gas turbine?

• Otto cycle

• Rankine cycle

• Brayton cycle

• Diesel cycle

The schematic shows which type of gas turbine system?

• Open cycle gas turbine system

• Closed cycle gas turbine system

In a closed cycle gas turbine system, what happens to the working fluid?

• It is expelled into the environment after passing through the turbine.

• It is recycled back into the compressor after completing the cycle.

• It undergoes a phase change before being reused in the system.

• It is converted into electrical energy and stored for later use.

What is a key characteristic of a single shaft gas turbine system?

• It allows for flexibility in operation with varying speeds and loads.

• It operates at a fixed speed and fixed load condition.

• It includes a mechanically independent power turbine.

• It is primarily used for train, car, and ship propulsion.

Answer explanation

In which application would a split shaft or multi-shaft gas turbine system be most advantageous?

• Fixed-speed power generation with consistent load.

• Applications requiring flexibility in operation such as propulsion for trains, cars, and ships.

• Systems requiring a single fixed-speed turbine operation.

• Simple applications with a constant load and speed.

What role does the mechanically independent power turbine play in a split shaft/multi-shaft system?

• It regulates the fuel supply to the combustor.

• It controls the exhaust gases leaving the system.

• It provides flexibility by operating independently of the compressor shaft.

• It maintains a fixed speed and load on the system.

Graph shown is Brayton cycle of gas turbines. What happens to the air at point 1 --> 2?

• Air gets heated

• Air is compressed

• Air expands

What is the shaft configuration of the gas turbine shown in the schematic?

• Single shaft

• Split shaft / multi-shaft

What is one of the main advantages of a COGEN (Combined Heat and Power) plant that combines electrical generation with LNG steam generation?

• It decreases the overall thermal efficiency to about 50%

• It increases the overall thermal efficiency to about 72%

• It requires separate facilities for electrical generation and steam generation

• It eliminates the need for an electrical generator entirely

What is a common reason for REUSING exhaust gases from a turbine rather than releasing them directly into the atmosphere?

• The exhaust gases are too cool to be released directly

• The exhaust gases are still at a relatively high temperature

• The exhaust gases are harmful to the turbine if not reused

• The exhaust gases need to be purified before release