Task 3Four stroke compression ignition engine operates on ideal Diesel cycle, it has a compression ratio of20 and a cut-off ratio of 1.3. At the beginning of the compression process, the working fluid is at 100kPa, 40 C, and 150 m³. This engine is operating at 2500 rpm. Assume cold air standard assumptionsat room temperature (i.e., constant specific heat), determine the following:A. The net-power output (kW)B. The thermal efficiency of the cycleC. The mean effective pressure (kPa)D. The mean effective pressure (kPa) and net-power output (kW) in the cycle if a two-strokeengine is being used instead of a four-stroke engine. Task 3Superheated steam at 575°C is routed from a boiler to the turbine of an electric power plant throughsteel tubes (k = 35 W/m K) of 300 mm inner diameter and 30 mm wall thickness. To reduce heat lossto the surroundings and to maintain a safe-to-touch outer surface temperature, a layer of calciumsilicate insulation (k = 0.10 W/m K) is applied to the tubes, while degradation of the insulation isreduced by degradation of the insulation is reduced by wrapping it in a thin sheet of aluminium havingan emissivity of = 0.20. The air and wall temperatures of the power plant are 27°C. Assume that theinner surface temperature of a steel tube corresponds to that of the steam and the convection coefficientoutside the aluminium sheet is 6 W/m²K,(a) What is the minimum insulation thickness needed to ensure that the temperature of thealuminium does not exceed 50°C?(b) What is the corresponding heat loss per unit meter?(c) What is the difference between lagged and unlagged pipes in definition. In addition, writedown the heat transfer formula for each pipe (i.e., lagged, and unlagged pipes).

TASK3: Given: The compression ratio, r = 20 The cutoff ratio, rc = 1.3 The pressure at the inlet of…

Task 3 Four stroke compression ignition engine operates on ideal Diesel cycle, it has a compression ratio of 20 and a cut-off ratio of 1.3. At the beginning of the compression process, the working fluid is at 100 kPa, 40 C, and 150 m³. This engine is operating at 2500 rpm. Assume cold air standard assumptions at room temperature (i.e., constant specific heat), determine the following: A. The net-power output (kW) B. The thermal efficiency of the cycle C. The mean effective pressure (kPa) D. The mean effective pressure (kPa) and net-power output (kW) in the cycle if a two-stroke engine is being used instead of a four-stroke engine.

Task 3 Four stroke compression ignition engine operates on ideal Diesel cycle, it has a compression ratio of 20 and a cut-off ratio of 1.3. At the beginning of the compression process, the working fluid is at 100 kPa, 40 C, and 150 m³. This engine is operating at 2500 rpm. Assume cold air standard assumptions at room temperature (i.e., constant specific heat), determine the following: A. The net-power output (kW) B. The thermal efficiency of the cycle C. The mean effective pressure (kPa) D. The mean effective pressure (kPa) and net-power output (kW) in the cycle if a two-stroke engine is being used instead of a four-stroke engine.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter7: Forced Convection Inside Tubes And Ducts

Section: Chapter Questions

Problem 7.5P

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Task 3Superheated steam at 575ºC is routed from a boiler to the turbine of an electric power plant through steel tubes (k = 35 W/m K) of 300 mm inner diameter and 30 mm wall thickness. To reduce heat loss to the surroundings and to maintain a safe-to-touch outer surface temperature, a layer of calcium silicate insulation (k = 0.10 W/m K) is applied to the tubes, while degradation of the insulation is reduced by degradation of the insulation is reduced by wrapping it in a thin sheet of aluminium having an emissivity of ε= 0.20. The air and wall temperatures of the power plant are 27ºC. Assume that the inner surface temperature of a steel tube corresponds to that of the steam and the convection coefficient outside the aluminium sheet is 6 W/m2 K, (a) What is the minimum insulation thickness needed to ensure that the temperature of the aluminium does not exceed 50ºC? (b) What is the corresponding heat loss per unit meter?(c) What is the difference between lagged and unlagged pipes in…
Superheated steam at 575ºC is routed from a boiler to the turbine of an electric power plant through steel tubes (k = 35 W/m K) of 300 mm inner diameter and 30 mm wall thickness. To reduce heat loss to the surroundings and to maintain a safe-to-touch outer surface temperature, a layer of calcium silicate insulation (k = 0.10 W/m K) is applied to the tubes, while degradation of the insulation is reduced by degradation of the insulation is reduced by wrapping it in a thin sheet of aluminium having an emissivity of ε= 0.20. The air and wall temperatures of the power plant are 27ºC. Assume that the inner surface temperature of a steel tube corresponds to that of the steam and the convection coefficient outside the aluminium sheet is 6 W/m2 K, (a) What is the minimum insulation thickness needed to ensure that the temperature of the aluminium does not exceed 50ºC? (b) What is the corresponding heat loss per unit meter?
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