A 25 MVA turbo-alternator is working on full load at a power factor of 0-8 and efficiency of 97%. Find the quantity of cooling air required per minute at full load, assuming that 90% of the total losses are dissipated by the internally circulating air. The inlet air temperature is 20° C and the temperature rise is 30° C. Given that specific heat of air is 0-24 and that 1 kg of air occupies 0-8 m3. [890 m3/minute] 6. A thermal station has an efficiency of 15% and 1·0 kg of coal burnt for every kWh generated. Determine the calorific value of coal. [5733 kcal/kg]

A 25 MVA turbo-alternator is working on full load at a power factor of 0-8 and efficiency of 97%. Find the quantity of cooling air required per minute at full load, assuming that 90% of the total losses are dissipated by the internally circulating air. The inlet air temperature is 20° C and the temperature rise is 30° C. Given that specific heat of air is 0-24 and that 1 kg of air occupies 0-8 m3. [890 m3/minute] 6. A thermal station has an efficiency of 15% and 1·0 kg of coal burnt for every kWh generated. Determine the calorific value of coal. [5733 kcal/kg]

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

b) Two alternators are connected in parallel to feed a load together. The no-load frequency of the first alternator is 51.5 Hz and its slope is 1MW / Hz. The no-load frequency of the second alternator is 51.0 Hz and its slope is 1MW / Hz. The total power of the load fed by these two alternators is 2.5MW and the power factor is 0.8. Accordingly, at what frequency does this system work and what are the power values transferred to the load by each alternator.
a) A sinewave is having a frequency of 50 Hz and instantaneous value of 150 Volts at 1.2 milli seconds. Find i) The maximum value of sinusoidal voltage waveform and i) The value of voltage at 1.7 milli seconds. b) Determine the instantaneous equation for the voltage waveform shown in figure, if Vp=100 Volts, Time period is 5 milli seconds and 0 =50 degrees. Vp i= 0 Upload your Answers steps in the "Final Answer Submission" Link provided in the Moodle. a) (i) Maximum value = a) (ii) Value of voltage at 1.7 ms b) Angular frequency %3D
Generate a conclusion on this following statements: Determine and analyze the voltage regulation characteristics of the alternator with resistive, capacitive, and inductive loading.
a) A sinewave is having a frequency of 100 Hz and instantaneous value of 150 Volts at 1.4 milli seconds. Find i) The maximum value of sinusoidal voltage waveform and ii) The value of voltage at 1.7 milli seconds. b) Determine the instantaneous equation for the voltage waveform shown in figure, if Vp=200 Volts, Time period is 5 milli seconds and 0 =40 degrees. Vp t = 0 Upload your Answers steps in the "Final Answer Submission" Link provided in the Moodle. a) (i) Maximum value = a) (ii) Value of voltage at 1.7 ms = b) Angular frequency =
Steam enters an adiabatic turbine at 6 MPa and 550 °C and leaves at 10 kPa and 50 °C. If the environment temperature and pressure is 0 °C and 103.325, what is the second law efficiency of the turbine? O a. 0.70 O b. 0.75 O c. 0.81 O d. 0.72 O e. 0.78
d) The generated voltage of a turbine at timet seconds is given by: v(t) = Vssin(0.4nt +=) 61 Where Vs is generator voltage in Volts. Evaluate the following: The voltage of the generator after 2.5 seconds if Vs = 70 V. The voltage at time t = 0 seconds to 3 significant figures The time when the generator first reaches maximum voltage, the period, the frequency, and the time displacement. ii. iv. V. Your answer to this part of the task should be supported by suitably annotated graphical evidence to help understanding by a non-technical audience. e) If the cable of this generator has a shape of the form: y = 70cosh(x/55)sinh²( Provide fully explained solutions to the following: The value of y when x = 10 to 3 significant figures The value of x when y = 40 to 3 significant figures Provide fully explained graphical evidence to show justify your answers to part (ii) vi. vii. viii.
The terminal voltage of a 150 kW series generator is 600 V at rated load. The armature resistance is 0.06 ohms and the series field resistance is 0.04 ohms. Find generated emf.
A 6-pole ,3 phase , 60 cycle alternator has 12 slots per pole and four conductor per slot. The winding is 5/6 pitch. There are 2,500,000 Maxwell ( 0.025 weber ) entering the armature from each north pole, and this flux sinusoidally distributed along the air gap. The armature coils are all connected in series , The winding is wye connected. Determine the open circuit emf of the alternator.
8-pole 3-phase star-connected alternator with 144 grooves in its armature rotates at 900 rpm. There are 12 conductors in each groove in the armature of the alternator. The magnetic flux of one pole is 1.8.10 ^ 6 maxwels. Coils (1-16) were wound in -15 steps. Accordingly, find the phase and interphase voltages induced in the inductor of the alternator. (The speed of the alternator will be taken as synchronous speed ns.)
Maz a) A sinewave is having a frequency of 50 Hz and instantaneous value of 250 Volts at 1.3 milli seconds. Find D The maximum value of sinusoidal voltage waveform and i) The value of voltage at 2.1 milli seconds. b) Determine the instantaneous equation for the voltage waveform shown in figure, if Vp=100 Volts, Time period is 10 milli seconds and 0 =40 degrees. on Vp Upload your Answers steps in the "Final Answer Submission" Link provided in the Moodle. a) (i) Maximnum value = a) (ii) Value of voltage at 2.1 ms = b) Angular frequency =
A 25 MVA turbo - alternator is working on full load at a power factor of 0-8 and efficiency of 97%. Find the quantity of cooling air required per minute at full load, assuming that 90% of the total losses are dissipated by the internally circulating air. The inlet air temperature is 20 ° C and the temperature rise is 30 ° C. Given that specific heat of air is 0-24 and that 1 kg of air occupies 0-8 m3. (890 m3 / minute
A 25 MVA turb0-alternator is working on full load at a power factor of 0-8 and efficiency of 97%. Find the quantity of cooling air required per minute at full load, assuming that 90% of the total losses are dissipated by the internally circulating air. The inlet air temperature is 20° C and the temperature rise is 30° C. Given that specific heat of air is 0-24 and that 1 kg of air occupies 0-8 m3. [890 m3/minute]