Q2: A 1.78 L four-stroke petrol engine was tested at 2500 rpm. The developed brake power is 28 kW and the brake specific fuel consumption (bsfc) is 290 g/kW.hr. Air consumption is measured by means of air-box method with orifice diameter 3.2-cm and discharge coefficient 0.62 and the pressure difference across the orifice is 150-mm-water. The ambient pressure and the temperature in the test room is 101 kPa and 20 °C. Assume: CV = 43.9 MJ/kg, PH20 =1 =10³ kg/m³, , comb = 98%, nmech 87%. (i) Determine the bmep, AFR, nv, power loss as friction, th,b. (ii) draw up the heat balance sheet on percentage basis, if the cooling water flow is 15 kg/min; rise in temperature of cooling water is 33 °C; exhaust gas temperature is 485 °C; Cpw is 4.2 kJ/kg.K and Cpexh is 1.25 kJ/kg.K.

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
icon
Related questions
Question
Q2: A 1.78 L four-stroke petrol engine was tested at 2500 rpm. The developed brake power is
28 kW and the brake specific fuel consumption (bsfc) is 290 g/kW.hr. Air consumption is
measured by means of air-box method with orifice diameter 3.2-cm and discharge coefficient
0.62 and the pressure difference across the orifice is 150-mm-water. The ambient pressure and
the temperature in the test room is 101 kPa and 20 °C. Assume: CV = 43.9 MJ/kg,
PH20 =10³ kg/m³, comb = 98%, mech = 87%. (i) Determine the bmep, AFR, №v, power loss as
friction, th,b. (ii) draw up the heat balance sheet on percentage basis, if the cooling water flow
is 15 kg/min; rise in temperature of cooling water is 33 °C; exhaust gas temperature is 485 °C;
Cpw is 4.2 kJ/kg.K and Cpexh is 1.25 kJ/kg.K.
Transcribed Image Text:Q2: A 1.78 L four-stroke petrol engine was tested at 2500 rpm. The developed brake power is 28 kW and the brake specific fuel consumption (bsfc) is 290 g/kW.hr. Air consumption is measured by means of air-box method with orifice diameter 3.2-cm and discharge coefficient 0.62 and the pressure difference across the orifice is 150-mm-water. The ambient pressure and the temperature in the test room is 101 kPa and 20 °C. Assume: CV = 43.9 MJ/kg, PH20 =10³ kg/m³, comb = 98%, mech = 87%. (i) Determine the bmep, AFR, №v, power loss as friction, th,b. (ii) draw up the heat balance sheet on percentage basis, if the cooling water flow is 15 kg/min; rise in temperature of cooling water is 33 °C; exhaust gas temperature is 485 °C; Cpw is 4.2 kJ/kg.K and Cpexh is 1.25 kJ/kg.K.
Expert Solution
steps

Step by step

Solved in 2 steps with 3 images

Blurred answer
Knowledge Booster
Fluid Dynamics
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY