Chapter 21

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2- What is normal air flow rate? How is air flow pressure measured? 4- Which engine produces the most torque (diesel or petrol)? why? 5- Mention the air fuel ratio required by the engine during (a) Starting time zero load (b) Normal running half load (C)full load 6- Types of lubrication in an IC engine?

bore and stroke of the fuel pump. 2. A 4-cylinder, 4-stroke, diesel engine, has the following parameters: brake power 100 hp, engine speed = 25 r.p.s, b.s.f.c. = 213 g/kW.hr, fuel density = 0.85 g/cm³, a = 1.2, and z = 1.25. Calculate: (i) Volume of fuel injected for one cylinder. (ii) Bore and stroke of the fuel pump. 3. A 4-stroko

In the arctic region, the minimum temperature at which the diesel can flow is -30°C, this is called its __________________ a. flash point  b. lower temperature point c . point d. flow point

Which does makes the volumetric efficiency of the reciprocating engine decrease? * Low cylinder head temperatures Improper valve timing Full throttle operation Sharp bends in the induction system High carburetor air temperatures When the piston reaches the bottom center it reverses direction and starts moving up on the compression stroke. TRUE OR FALSE? * Your answer What happens with the volumetric efficiency when the engine's heat increases? Your answer As an aircraft climbs, air density decreases, thereby decreasing the amount of air in the fuel/air mixture. This results in a vibrant air/fuel mixture which causes a reduction in engine power. TRUE OR FALSE? * Your answer

It is a multiple choice marine diesel engine question, please specify the correct option.

What do you mean by intake stroke?

Discuss the main functions of the lubricating system of an engine

3 litters, 4 cylinders engine, multipoint port fuel injection, one for each cylinder. AF ratio is 14.6, the volumetric efficiency is 90%. The engine speed at idle condition is 550 rpm with stoichiometric gasoline and inlet pressure is 30 kPa. But the engine speed is 5900 rpm with stoichiometric gasoline of maximum power, the inlet pressure is 101 kPa. Calculate the following: a. mass air flow rate in one cylinder at maximum speed, b. mass fuel flow rate into one cylinder through an injector, c. mass air flow into one cylinder at idle speed, d. mass fuel flow rate into one cylinder at idle speed, e. injection pulse duration is seconds at idle conditions at idle, f. injection pulse duration is degrees of engine rotation at idle conditions.

The gas/oil mixture used in a two stroke engine has been properly mixed. The carburetor high speed & cruise circuit is adjusted to lean. Tech a says that the lean adjustment may cause the engine to fail due to improper lubrication: tech b says that it may cause the engine to fail because of overheating. Who is correct?

I need the answer as soon as possible

An HCCI engine needs to compress a fuel-air mixture to 1300 K at top dead center for proper auto- ignition. Assuming a residual gas fraction f of 0.35 at a temperature of 750 K, what should the inlet air temperature be if a.) the compression ratio is 11:1, and b.) the compression ratio is 18:1 ? Assume the specific heat ratio y = 1.35. The problem states that f = 0.35 T = 750 K (exhaust)

A engine develops power output for each two engine revolution. * Your answer It is the difference in expansion amounts between the cylinder head and pushrod that effectively increases the space between the valve stem and the rocker's arm. * Your answer On a four-stroke cycle reciprocating engine, which strokes are both valves close? * Intake Power Ignition Compression Exhaust It represents the net power output of the engine at the crankshaft. * Your answer If the fuel/air ratio is proper and ignition timing is correct, the combustion process should be completed just after center at the beginning of the power stroke. * Your answer

The injector function in diesel engine is to a. inject fuel continusously when engine is running. b. inject fuel at the beginning of comprssion stroke c. inject fuel at the end of expansion stroke d. inject fuel at end of compression stroke

please specify the option (It is a marine diesel engine question)

a. Discuss the different parameters being analyzed in the overall performance of the engine  b. What is the difference between RFG and RFS?  c. Explain the difference of the combustion processes involved between SI and CI engines?

I need the answer quickly

explain? 2- Explain the differences and similarities between the engine temperature sensitivity and the incoming air temperature. How do they influence the balance of the injected fuel volume determined by the ECU?

Which of the following is not a true statement about diesel engines?a. The operation and main components of a diesel engine are comparable to those of a gasoline engine. Diesel and gasoline engines are available as four- stroke combustion cycle engines. Diesel engines rely on glow plugs instead of spark plugs to initiate ignition. The compression ratio of diesel engines is typically three times that of a gasoline engine.

It is a multiple choice marine diesel engine question, please specify the correct option.

C- Fill the blank 1- Internal combustion engines classified according to air intake into the cylinder to and-- 2- Typical compression ratio for modern gasoline engine lie between 3- There are a number of gasoline additives that are used to raise the octane number such as 4- Higher compression ratio in SI engine lead to 5- The thermal efficiency of CI engine is than of SI engine. 6- Fuel with octane number of 78 indicate 78%- -and 22%- 7- Anti-Knock quality improves with - no. of carbon atoms. 8- Higher compression ratio in SI engine lead to 9- Maximum power overtaking a vehicle or climbing up a hill (extra load) this requires a mixture.

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Which of the following are complexities that are ignored when assuming air-standard for an internal-combustion engine? Select all that apply. Variation of specific heat values with a change in temperature Changes in pressure during the power stroke (expansion) Changes in chemical composition due to combustion O Heat transfer through the piston or cylinder walls

tech a says that the float type carburetor is the least efficient design used on Briggs engines. Tech b says that Briggs carburetors typically have their mixture screws adjusted to 4 turns out. Who is correct?

is it true that an l head engine has the intake and exhaust valves mounted in the cylinder head

How many degrees the crankshaft will rotate with both the intake and exhaust valves seated when the intake opens 20 deg. BTDC, the exhaust opens 55 deg. BBDC, intake closes 25 deg. ABDC, and exhaust closes 45 deg. ATDC. (TYPE NUMBERS ONLY, AND THE UNIT IS DEG. AND ANSWER IN WHOLE NUMBERS ONLY) * Your answer On a four-stroke cycle reciprocating engine, which strokes are both valves open? * Power Compression Intake Exhaust Ignition The primary concern in the firing order of the opposed engine is to keep the power impulses on adjacent cylinders as close as possible to obtain the most outstanding mechanical efficiency. TRUE OR FALSE? * Your answer A nine-cylinder engine with a bore of 5.5 inches and a stroke of 6 inches will have a total piston displacement of? (TYPE NUMBERS ONLY, AND THE UNIT IS CU. INCH AND ANSWER IN WHOLE NUMBERS ONLY) * Your answer

What are the major pollutants from the exhaust of SI and CI engines.

Explain briefly 1. Valve lag 2. intake lag

Explain working method of rotary distributor injection pump of diesel engines.

please specify the option (It is a marine diesel engine question)

1. Discuss an Internal combustion Engine? 2. Briefly explain a 2 and 4 stroke Engines and how each operation. Add a caption... > Status (Contacts)

What is the injection duration (deg) needed for fuel injection in a single cylinder dieselengine operating at 1500 rpm so that the engine produces 50 kW? The engine bsfc is 0.22kg/kWh. Assume incompressible fuel flow, an average cylinder pressure of 50 bar duringthe fuel injection, an injector effective area ?f = 1.0 mm2, and an injection pressureequal to 550 bar