Testing of ICE

Two automobile engines have the same total displacement volume and the same total power produced within the cylinders. List the possible advantages of V6 over a straight line (in line).

What is the friction power for IC engine? How this power can be reduced?

In a test of single cylinder engine with bore $30 \text{ cm}$, stroke $45 \text{ cm}$ and working on 4-stroke cycle, the following observations were made:
Duration of trial $= 1 \text{ hour}$, total fuel consumption $= 8 \text{ kg}$, heating value of fuel $= 45000 \text{ kJ/kg}$, total revolutions made $= 12000$, indicated mean effective pressure $= 6 \text{ bar}$, brake load $= 1500 \text{ N}$, torque arm $= 92 \text{ cm}$. Find, indicated power, brake power, mechanical efficiency, thermal efficiency.

Differentiate between indicated power and brake power.

How constant volume combustion and constant pressure combustion are differed from each other? Where do these combustion happen?

A four-stroke four-cylinder automotive engine develops 150 Nm brake torque at 3000 rpm. Assuming brake mean effective pressure to be 0.925 bar and mean piston speed to be 12 m/s. Find (i) brake power, (ii) displacement volume, (iii) stroke and (iv) bore.

What are the purposes of testing of IC engine? Define indicated horse power, indicated mean effective pressure, brake horse power, specific fuel consumption and A/F ratio.

An engine develops a brake power of 3.7 kW. It's indicated thermal efficiency is 30%, mechanical efficiency is 80%, heating value of the fuel is 42,000 kJ/kg and its specific gravity = 0.88. Calculate (i) the fuel consumption rate, (ii) indicated specific fuel consumption, (iii) brake specific fuel consumption.

Why idling of SIE requires rich mixture?

Differentiate between part fuel injection and gasoline direct injection. Which process is more advantageous?

A four stroke gasoline engine has a volumetric efficiency of 0.84. It has 12 cylinders, 150 mm bore, 200 mm stroke, and runs at 1500 rpm with indicated thermal efficiency of 0.30. The overall fuel-air ratio is 0.08 and density of air in the manifold is $0.82 \text{ kg/m}^3$. Compute the indicated mean effective pressure and indicated power. Heat of combustion = 42000 kJ/kg.

How IC engine performance measured? Name five parameters to measure the performance. How significant these parameters are to measure the performance of an IC engine?

The following readings are recorded from a single cylinder diesel engine working on 4-stroke cycle:

• The suction conditions are 1 bar and 50°C
• Brake power developed = 260 kW, rpm = 1500
• Volumetric efficiency = 80%, Air-fuel ratio = 18
• Specific fuel consumption = 0.25 kg/kW-h on brake power basis.

Determine the dimensions of the engine cylinders taking stroke to bore ratio 1.25.

What is internal combustion engine? Compare SI and CI engine with respect to i) compression ratio ii) ignition iii) Speed

In a performance test on a four-stroke engine, the indicator diagram area was found to be $5 \times 10^{-4}\text{ m}^2$ and the length of the indicator diagram was $0.05\text{ m}$. If the y-axis has a scale of $1\text{ m} = 50\text{ MPa}$, find the indicated mean effective pressure of the engine given that bore=$150\text{mm}$, stroke=$200\text{mm}$. The measured engine speed was $1200\text{ rpm}$. Also calculate the indicated power and indicated specific fuel consumption of the engine if the fuel injected per cycle is $0.5\text{ cc}$ with the specific gravity $0.8$.

Why idling of SIE requires a rich mixture?

What is nozzle? What are the functions of a nozzle in CIE?

A four stroke gasoline engine has a volumetric efficiency of $0.83$. It has 12 cylinders, $150\text{ mm}$ bore, $200\text{ mm}$ stroke and runs at $1500\text{ rpm}$ with indicated thermal efficiency of $0.31$. The overall fuel-air ratio is $0.08$ and density of air in the manifold is $0.81\text{ kg/m}^3$. Compute the indicated mean effective pressure and indicated power. Heat of combustion is $42000\text{ kJ/kg}$.