Saturated liquid refrigerant R-134a is throttled from 900 to 90
kPa at a rate of 0.32...
Saturated liquid refrigerant R-134a is throttled from 900 to 90
kPa at a rate of 0.32 kg/s. What is the rate of entropy generation
for this throttling process? kW/K
Refrigerant-134a is throttled from the saturated liquid state at
700 kPa to a pressure of 160 kPa. Determine the temperature drop
during this process and the final specific volume of the
refrigerant.
Refrigerant-134a enters an adiabatic compressor as saturated
vapor at 160 kPa at a rate of 2.8 m3/min and is
compressed to a pressure of 900 kPa. Determine the minimum power
that must be supplied to the compressor. Use the tables for
R-134a.
The minimum power that must be supplied to the compressor
Refrigerant-134a enters the condenser of a residential heat pump
at 900 kPa and 65oC at a rate of 0.018 kg/s and leaves
at 750 kPa subcooled by 2oC. The refrigerant enters the
compressor at 200 kPa superheated by 3oC. Determine (a)
the isentropic efficiency of the compressor in decimal (up to two
decimals), (b) the rate of heat supplied to the heated room, and
(c) the COP of the heat pump. Also determine (d) the COP if this
heat pump...
Refrigerant R-134a enters the compressor of a refrigeration
machine at 140 kPa pressure and -10 ° C temperature and exits at 1
MPa pressure. The volumetric flow of the refrigerant entering the
compressor is 0.23 m3 / minute. The refrigerant enters the
throttling valve at 0.95 MPa pressure and 30 ° C, exiting the
evaporator as saturated steam at -18 ° C. The adiabatic efficiency
of the compressor is 78%. Show the cycle in the T-s diagram. In
addition,
a)...
Refrigerant 134a, initially (state 1) a saturated liquid at
-80C, is contained in a piston-cylinder assembly. The water
undergoes a process to the corresponding saturated vapor (state 2),
during which the piston moves freely in the cylinder. The change of
state is brought about by heating the water as it undergoes an
internally reversible process at constant pressure and temperature.
If the mass of the refrigerant is 0.1 kg, determine (a) heat
transfer using first law of thermodynamics in kJ...
R-134a expands through a throttling device from 900 kPA and 30
oC to -10 oC.
a- determine the entropy generation of this process.
b- the working fluid R-134a, this time expands adiabatically
through a low pressure turbine with 90% isentropic efficiency from
900 kPa and 30 oC to -10 oC. What is the power generated by this
turbine per unit mass flow rate of R134-a, in kj/kg.
Saturated water vapor at 1000 kPa is throttled to 100 kPa. The
velocity of the steam remains constant through the process.
Determine the exit temperature of the water vapor. I know this is
already awnsered in a solution for 1st edition but can someone help
me understand what they do and how they picked the numbers they did
from some table to get the exit temperature?
A 10-ft3 tank contains a saturated mixture of refrigerant R-134a
at a pressure of 40 psia. If the saturated liquid occupies 2% of
the volume, determine the a) total mass (lbm) b) quality c) average
internal energy (Btu lbm) d) temperature (℉).
A steady-flow Carnot refrigeration cycle uses refrigerant-134a
as the working fluid. The refrigerant changes from saturated vapor
to saturated liquid at 40 C in the condenser as it rejects heat.
The evaporator pressure is 120 kPa. Determine: (a) the amount of
heat absorbed from the refrigerated space; qL = _______________
kJ/kg (b) the net work input; and wnet = ______________ kJ/kg (c)
the coefficient of performance of the system. COP =
_____________
A commercial refrigerant that uses R-134a as the refrigerant is
used for cooling, to keep the condition at -35o, throws heat into
the cooling water that has been in the condenser at 18oC and 0.25kg
/ s and has been formed since 26o. The refrigerant enters the
condenser at 1.2 MPa and 50o ° and exits by cooling 5o C more than
the saturation temperature at the same pressure. If the compressor
consumes 3.3 kW (Answer: 0.0498 kg / s,...