Chapter 6, Problem 6.8DOEP

Please provide complete solution with units of measurement.

Using the basic relations given below and detailing your method and assumptions,Develop all the analytical relations required to:1) Determine the temperatures and pressures at all stages of an ideal air-standard SIOtto cycle analysis2) Show that the thermal efficiency of any internal combustion engine can besimplified as a ratio of temperature differences 3) Discuss the concept of Brake Specific Fuel Consumption (BSFC) and propose a rationale for the Figure 1 below (in other words, explain why the BSFC is decreasingbefore increasing with engine speed)

As a mechanical engineer, you were asked by your supervisor to monitor the operation of 4-stroke engine; as a result you got the following readings: > Imep = 780 kN/ m2 > Engine speed = 800 rpm > Brake Power 30 kW %3D %3D > nm = 85 % > B/S 0.7 You noticed also, that the inlet valve opens 10° before TDC and closes40° after BDC and it takes 0.0035 second after ignition for the charge to gain maximum pressure. Depending on the above readings, find the following engine parameters: a. The crank angle when the spark occursfor the maximum pressure to be at TDC b. The time period in second of inlet valve opening during one cycle c. The diameter of the engine d. The average piston speed 1 Upload file

1

Q1. During a test on a two stroke diesel engine on full load the following observations were recorded: Speed= 350 rpm Net brake load= 590 N Mean effective pressure= 2.8 bar Fuel consumption=4.3 kg/h_ Jacket cooling water= 500 kg/h Temperature of jacket water at inlet and outlet=25°C and Soyc respectively Air used per kg of fuel= 33kg Temperature of air in test room= 25°C Temperature of exhaust gases= 400°c Cylinder diameter= 220 mm In solve to find mass of steam in exhaust gases m=(4.3/3600) *0.15 *9 Stroke length= 280 mm want clarification of the value 9 bleas Effective brake diameter= 1 m Calorific value= 43900 KJ/kg Proportion of hydrogen in fuel= 15% Mean specific heat of dry exhaust gases= 1.0 KI/kg K Specific heat of steam= 2.09 KJ/kg K Calculate: (1) indicated power (2) brake power (3) draw up heat balance sheel on minute basis.

Please , solve all two questions completely by clear handwritten

As mechanical engineer, if you are requested to test a 4-stroke, 5-cylinder engine and you recorded the following data; Engine bore and stroke are 110 mm and 130 mm. respectively, Engine speed = 2000 rpm , Fuel consumption = 0.4 kg/min, Fuel heating value = 44000 kJ/kg, Tension difference on either side of the brake pulley = 45 kg, Brake circumference = 420 cm , Mechanical efficiency = 90%, Ambient temperature and ambient pressure are 20 ° C and 1 atm, respectively, Volumetric flow rate of air to the engine = 1.92 m/min. Consider the mentioned data then answer the following questions: %3D %3D a. Find the indicated thermal efficiency b. Find the indicated mean effective pressure. c. Find the brake specific fuel consumption Tind thA valumatuin offiniene

(a) A very important component of a system has a mean time between failures of 100 hr and a mean time to repair of 10 hr. Determine the inherent availability of the system.           (b) If the equipment in Q7 (c i) above is required to meet an inherent availability requirement of 0.985 and a mean time between failures of 100 hr. Calculate the permissible mean time to repair and if the system as a mean of the time intervals between corrective maintenance actions of 900 hrs and the sum of the mean corrective maintenance time intervals including supply downtime and administrative down time of 10 hrs Determine the operational availability of the system

Engine Type Four cylinder Four stroke Diesel engine, Bore: 0.073m, Stroke: 0.0889m Capacity: 1489cc, Power: 36 H.P. at 4000 rpm, Torque : 8.5 kg.m at 2250 rpm and Compression Ratio :17.3:1 Explain how to measure the :- (i) Fuel consumption. (ii) (iii) RPM, power output etc. (iv) Study of various components of diesel engine. Manometer readings for air flow.