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...

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