Rankine Cycles 1. A 90 MW coal-fired steam power plant working on a Rankine cycle operates between a boiler pressure of 3 MPa and a condenser pressure of 3 kPa. The steam is superheated to 450 °C at entry to the turbine. Assuming an ideal cycle of operations: (a) Draw a labeled schematic of the system and a T-s diagram to describe the cycle. (b) Determine the net work output, per kg of steam (c) Determine the heat energy supplied at the boiler, per kg of steam (d) Determine the cycle efficiency (e) Determine how much coal needs to be supplied to the plant per day, if the coal has a calorific value of 29300 kJ/kg. It can be assumed that all of the energy from the coal is transferred to the steam in the boiler and the plant operates 24 hours per day. (Ans: 38.3%; 691200 kg)

Rankine Cycles 1. A 90 MW coal-fired steam power plant working on a Rankine cycle operates between a boiler pressure of 3 MPa and a condenser pressure of 3 kPa. The steam is superheated to 450 °C at entry to the turbine. Assuming an ideal cycle of operations: (a) Draw a labeled schematic of the system and a T-s diagram to describe the cycle. (b) Determine the net work output, per kg of steam (c) Determine the heat energy supplied at the boiler, per kg of steam (d) Determine the cycle efficiency (e) Determine how much coal needs to be supplied to the plant per day, if the coal has a calorific value of 29300 kJ/kg. It can be assumed that all of the energy from the coal is transferred to the steam in the boiler and the plant operates 24 hours per day. (Ans: 38.3%; 691200 kg)

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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