Thermal Power Engineering

Exhaust steam from a turbine enters a condenser with a specific enthalpy of 2164 kJ/kg and a velocity of 75 m/s. During the cooling process, the heat loss to the cooling water per kg of working fluid is 1680 kJ/kg. The condensate exits the system with a velocity of 12 m/s. Sketch a systems diagram for the condenser and determine the specific enthalpy of the working fluid at exit from the condenser.

Thermal Power Engineering

Dry saturated steam at p1 = 3.5 MPa is contained in a cylinder-piston arrangement. It is brought into thermal contact with a heat sink at TR = 175K. The steam rejects Q12 = 16 MJ of heat during a constant pressure process. The mass of steam is m = 10 kg. Determine (a) final state ‘2’ of steam, (b) change in entropy of steam (∆S12), and (c) change in entropy of the universe (∆SU ).

Thermal Power Engineering

Propane gas is to be burned in a furnace at the rate of 1000 LPH at STP, using 15%

excess air. For achieving energy efficient operation, preheated air at 100 C is to be used.

Assume that the ambient air completely dry and at 1 atm absolute pressure is available at

10oC. Calculate the energy required for heating the air (in kJ/h) from 10C to 100oC.

Thermal Power Engineering

Air at 1 atm absolute pressure, 38oC and 80% relative humidity is to be cooled to 18oC

and fed into a plant area at a rate of 510 m3

/min (STP). Calculate the rate (kg/min) at which

water condenses

and fed into a plant area at a rate of 510 m3

/min (STP). Calculate the rate (kg/min) at which

water condenses

Thermal Power Engineering

A shell-and-tube process heater is to be selected to heat water (cp = 4190 J/kg · °C) from 20°C to 90°C by steam flowing on the shell side. The heat transfer load of the heater is 600 kW. If the inner diameter of the tubes is 1 cm and the velocity of water is not to exceed 3 m/s, determine how many tubes need to be used in the heat exchanger.

Thermal Power Engineering

Due to the remoteness and dispersed population of small islands, standalone PV

systems can play a significant role in providing energy access. Consider a typical

island in your country and size a PV system that can provide sufficient electricity to

a small school there. Start with a list of typical appliances and their duty cycles,

solar resource and meteorological conditions at the location and choose suitable

system components. Also carry out a simple cost- benefit analysis in comparison to

a diesel generator based system.

systems can play a significant role in providing energy access. Consider a typical

island in your country and size a PV system that can provide sufficient electricity to

a small school there. Start with a list of typical appliances and their duty cycles,

solar resource and meteorological conditions at the location and choose suitable

system components. Also carry out a simple cost- benefit analysis in comparison to

a diesel generator based system.

Thermal Power Engineering

A hot aquifer of height h km , cross-sectional area A km2 and porosity p’ is located at a depth of z km. Derive expressions for the energy and power available at a given time t . Also, determine the time constant for energy extraction and explain its significance.

Thermal Power Engineering

calculate the total upward force on a valve disc 2.5 inch in diameter if safety valve neck diameter is 3 inch and valve outlet diameter is 4 inch when the boiler steam pressure is 160 bar

Thermal Power Engineering

Air initially at 3000 0F and 600 psia expands isentropically under non-flow condiions. The final volume is six times the initial volume. Show the process on the p-V and T-s coordinates and find a.) the final pressure, psia; b.) the final temperature, 0F; c.) the heat transferred, BTU/lbm; d.) the work done, BTU/lbm; e.) the change of entropy, BTU/lbm.0R.

Thermal Power Engineering

Air initially at 400K expands in a constant pressure non-flow process until he initial volume is doubled. Find, a.) the heat transfer, kJ/kg; b.) the work, kJ/kg; and c.) the change in entropy, kJ/kg-K, for the process.