Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470501979
Author: Frank P. Incropera, David P. DeWitt, Theodore L. Bergman, Adrienne S. Lavine
Publisher: Wiley, John & Sons, Incorporated
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Chapter 11, Problem 11.75P
a.
To determine
The power required by the motor.
B.
To determine
To calculate the refrigerator in each segment and the power required by the motor?
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A manufacturer conducted an experiment for an
evaporator capacity 507 kW cooling and designed for
high COP of 1.8 when using lithium bromide plus
water in an absorption refrigeration system. The
evaporator operates 20 C, condenser 40 C &
absorber 45 C supplying 1.4 kg/s of water plus lithium
bromide solution to the generator. For a condenser
size of 694 kW,
determine:
Heat provided by the generator
&
absorber capacity in kW
Reinneil Law-ay
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7. (a) Compute the possible maximum efficiency of a heat
engine operating between the temperature limits of 147*C
and 698*C.
(b) A refrigerator has COP of 6. How much work must be
supplied to the refrigerator in order to
remove 45 cal of heat from its interion?
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II
An air-conditioning absorption system has an evaporator capacity of 350 kW with a COP of 0.90 operating at a temperature of 25 C with a condensing temperature of 35 C. The same cooling tower was used to reject the heat from the condenser and the absorber operating 45 C & providing 1 kg/s of water plus lithium bromide solution to the generator. Consider the heat rejection ratio of condenser to evaporator is 1.05, Determine the following:
1. Heat given by the generator & the size of condenser in kW
2. Leaving condenser & evaporator enthalpies & the mass of refrigerant water flowing from the generator to the condenser then to the evaporator & to the absorber (using evaporator heat balance). 3. Weight of lithium bromide in kg/s, concentration in percent & enthalpy from the absorber to the generator in kJ/kg
4. Enthalpy from the generator to condenser in kJ/kg (using condenser heat balance) & concentration in percent & enthalpy from generator to absorber…
Chapter 11 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 11 - In a fire-tube boiler, hot products of combustion...Ch. 11 - A shell-and-tube heat exchanger is to heat an...Ch. 11 - A steel tube (k=50W/mK) of inner and outer...Ch. 11 - A heat recovery device involves transferring...Ch. 11 - A novel design for a condenser consists of a tube...Ch. 11 - The condenser of a steam power plant...Ch. 11 - Thin-walled aluminum tubes of diameter D = 10mmare...Ch. 11 - A tinned-tube, cross-how heat exchanger is to use...Ch. 11 - Water at a rate of 45,500kg/h is heated from 80...Ch. 11 - A novel heat exchanger concept consists of a...
Ch. 11 - Prob. 11.12PCh. 11 - A process fluid having a specific heat of...Ch. 11 - A shell-and-tube exchanger (two shells, four tube...Ch. 11 - Consider the heat exchanger of Problem 11.14....Ch. 11 - The hot and cold inlet temperatures to a...Ch. 11 - A concentric tube heat exchanger of length L = 2 m...Ch. 11 - A counterflow, concentric tube heat exchanger is...Ch. 11 - Consider a concentric tube heat exchanger with an...Ch. 11 - A shell-and-tube heat exchanger must be designed...Ch. 11 - A concentric tube heat exchanger for cooling...Ch. 11 - A counterflow, concentric tube heat exchanger used...Ch. 11 - An automobile radiator may be viewed as a...Ch. 11 - Hot air for a large-scale drying operation is to...Ch. 11 - In a dairy operation, milk at a flow rate of 250...Ch. 11 - The compartment heater of an automobile...Ch. 11 - A counterflow, twin-tube heat exchanger is made...Ch. 11 - Consider a coupled shell-in-tube heat exchange...Ch. 11 - For health reasons, public spaces require the...Ch. 11 - A shell-and-tube heat exchanger (1 shell pass, 2...Ch. 11 - Saturated water vapor leaves a steam turbine at a...Ch. 11 - The human brain is especially sensitive to...Ch. 11 - Prob. 11.47PCh. 11 - A plate-tin heat exchanger is used to condense a...Ch. 11 - In a supercomputer, signal propagation delays...Ch. 11 - Untapped geothermal sites in the United States...Ch. 11 - A shell-and-tube heat exchanger consists of 135...Ch. 11 - An ocean thermal energy conversion system is...Ch. 11 - Prob. 11.55PCh. 11 - Prob. 11.56PCh. 11 - The chief engineer at a university that is...Ch. 11 - A shell-and-tube heat exchanger with one shell...Ch. 11 - Prob. 11.59PCh. 11 - Prob. 11.60PCh. 11 - Prob. 11.61PCh. 11 - Prob. 11.62PCh. 11 - A recuperator is a heat exchanger that heats air...Ch. 11 - Prob. 11.64PCh. 11 - Prob. 11.65PCh. 11 - A cross-flow heat exchanger consists of a bundle...Ch. 11 - Exhaust gas from a furnace is used to preheat the...Ch. 11 - Prob. 11.68PCh. 11 - A liquefied natural gas (LNG) regasification...Ch. 11 - Prob. 11.70PCh. 11 - A shell-and-tube heat exchanger consisting of...Ch. 11 - Prob. 11.73PCh. 11 - The power needed to overcome wind and friction...Ch. 11 - Prob. 11.75PCh. 11 - Consider a Rankine cycle with saturated steam...Ch. 11 - Consider the Rankine cycle of Problem 11.77,...Ch. 11 - Prob. 11.79PCh. 11 - Prob. 11.80PCh. 11 - Hot exhaust gases are used in a...Ch. 11 - Prob. 11.84PCh. 11 - Prob. 11.90PCh. 11 - Prob. 11S.1PCh. 11 - Prob. 11S.2PCh. 11 - Prob. 11S.3PCh. 11 - Solve Problem 11.15 using the LMTD method.Ch. 11 - Prob. 11S.5PCh. 11 - Prob. 11S.6PCh. 11 - Prob. 11S.8PCh. 11 - Prob. 11S.10PCh. 11 - Prob. 11S.11PCh. 11 - A cooling coil consists of a bank of aluminum...Ch. 11 - Prob. 11S.17P
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