FE/EIT sample problems from EIT/FE exam for dynamics
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Chapter 3 Problems from Quantitative Analysis for Management by Render
pdc chapter 3 problems by Venkata Rao K., Rama Sudha K. and Manmadha Rao G.Descripción completa
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pdc chapter 3 problems by Venkata Rao K., Rama Sudha K. and Manmadha Rao G.Full description
Challenge Problems for Precalculus students. This accompanies our Unit 3 - Logs and Exponents
solved financial accounting chap 4Full description
rsgar ta4t 4t at4e ta4t 4 a4tFull description
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Sample Problems
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Calculate the heat transfer in kJ per hour through a solid brick wall 6 m long, 2.9 m high, and 225 mm thick, when the outer surface is at 5C and the inner surface is 17C, the coefficient of thermal conductivity of the brick is 0.6 W/m-K.
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A vertical furnace wall is made up of an inner wall of firebrick 20 cm thick followed by insulating brick 15 cm thick and an outer wall of steel 1 cm thick. The surface temperature of the wall adjacent to the combustion chamber is 1200C while that of the surface of steel is 50C. The thermal conductivities of the wall is 0.26 W/m-K; insulating brick at 10 W/m-K; and steel at 45 W/m-K. Neglecting the film resistances and contact resistance of joints, determine the heat loss per square meter of wall area.
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A composite wall is made up of an external thickness of brickwork 110 mm thick inside which is a layer of fibreglass 75 mm thick. The fiberglass is faced internally by an insulating board 25 mm thick. The coefficient of thermal conductivity for the three are as follows: Brickwork-1.5W/m-K; Fiberglass-0.04 W/m-K; Insulating board-0.06 W-mK. The surface transfer coefficients of the inside wall is 3.1W/m2-K while that of the outside is 2.5 W/ m2-K. Take the internal ambient temperature as 10C and the external temperature is 27C. Determine the heat loss through such wall 6 m high and 10 m long.
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A heat exchanger is to be designed for the following specifications: Hot gas temperature = 1145C; Cold gas temperature = 45C; Convective film coefficient on the hot side = 230 W/m2-K; Convective film coefficient on the cold side = 290 W/m2-K; thermal conductivity of the metal wall = 115 W/m-K. Find the maximum thickness of the metal wall between the hot gas and the cold gas so that the maximum temperature of the wall does not exceed 545C.
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A 3mm diameter and 5m long electric wire is tightly wrapped with a 2mm thick plastic cover whose thermal conductivity is 0.15 W/m-K. Electrical measurement indicate that a current of 10A passes through a wire and there is a voltage drop of 8V along the wire. If the insulated wire is exposed to a medium at 30C, with heat transfer coefficient h=12 W/m2-K, determine the interface temperature of the wire.
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An insulated steam pipe located where the ambient temperature is 32C, has an inside diameter of 50mm with 10mm thick wall. The outside diameter of the corrugated asbestos insulation is 125mm and the surface coefficient of still air, ho = 12 W/ m2-K. Inside the pipe is steam having a temperature of 150C with film coefficient hi = 6000 W/m2-K. Thermal conductivity of pipe and asbestos insulation are 45 and 0.12 W/m-K, respectively. Determine the heat loss per unit length of pipe.
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How many watts will be radiated from a spherical black body 15 min diameter at a temperature of 800C?
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At an average temperature of 100C, hot air flows through a 2.5 m long tube with an inside diameter of 50 mm. The temperature of the tube is 20C along its entire length. Convective film coefficient os 20.1 W/m2-K. Determine the convective heat transfer from air to the tube.
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How many tons of refrigeration are required to produce 10 metric tons of ice per day at -15C from raw water at 25C if miscellaneous losses are 15% of the chilling and freezing load?
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A creamery must cool 20,000L of milk received each day from initial temperature of 29C to a final temperature of 2C in 5 hours. If refrigeration losses amount to 10% of the chilling load, what must be the capacity of the refrigerating machine in TOR?
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Magnolia Dairy products plant must cool 4000 gallons of fresh milk received from the farm per day from an initial temperature of 80F to a temperature of 38F in 5 hours. If the density of milk is 8.6lb/gal and specific heat is 0.935 BTU/lb-R, what must be the capacity of the refrigerating machine in TOR?
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Fish weighing 11,000 kg with a temperature of 20C is brought to a cold storage and which shall be cooled to -10C in 11 hours. Find the required plant refrigerating capacity in TOR if the specific heat of fish is 0.7 kCal/kg-K above freezing and 0.30 kCal/ kg-K below freezing point which is -3C. The latent heat of freezing is 55.5 kCal/kg.
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An ideal vapor compression cycle requires 5 kW to power the compressor. You have found the following data for the cycle: the enthalpy at the condenser entrance = 203 kJ/kg,exit = 55kJ/kg; evaporator exit = 178 kJ/kg. If the mass flow rate of the refrigerant is 0.20 kg/s, then the coefficient of performance of this refrigeration cycle is most nearly:
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A refrigeration system operates on an ideal vapour compression using R-12 with an evaporator temperature of -30C and a condenser exit temperature of 49.30C and requires 74.6kW motor to drive the compressor. What is the capacity of the refrigerator in TOR? Enthalpy at condenser entrance = 382 kJ/kg, exit = 248.15 kJ/kg, at evaporator entrance = 248.15 kJ/kg, exit = 338.14 kJ/kg.
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A refrigerator is 2 m high, 1.2 m wide and 1 m deep. The overall heat transfer coefficient is 0.532 W/m^2-K. How many kilograms of 0C ice will melt per hour if the inside temperature is maintained at 10C while the surrounding air temperature is 35C?
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In a CO2 refrigerating plant, the specific enthalpy of the refrigerant as it leaves the condenser is 135 kJ/kg and as it leaves the evaporator it is 320 kJ/ kg. If the mass flow of the refrigerant is 5 kg/min, calculate the refrigerating capacity per hour.
