Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80°f with a velocity of 1453.4 ft/s. at the exit, the tem
perature is 280°f and the velocity is negligible. the diffuser operates at steady state and potential energy effects can be neglected. determine the exit pressure in lbf/in2 .
1 answer:
Refer to the diagram shown below.
State 1: The inlet
T₁ = 80°F, the inlet temperature
v₁ = 1453 ft/s, the inlet velocity
Saturated vapor
From thermodynamic tables, obtain
h₁ = 113.94 Btu/lbm, the enthalpy
p₁ = 101.45 psia, the inlet pressure
State 2: The outlet
T₂ = 280 F, the outlet temperature
v₂ = 0, the outlet velocity
From thermodynamic tables, obtain
h₂ = 163.76 Btu/(lbm-R)
p₂ = 40 psia, the exit pressure
Answer: 40 psia
State 1: The inlet
T₁ = 80°F, the inlet temperature
v₁ = 1453 ft/s, the inlet velocity
Saturated vapor
From thermodynamic tables, obtain
h₁ = 113.94 Btu/lbm, the enthalpy
p₁ = 101.45 psia, the inlet pressure
State 2: The outlet
T₂ = 280 F, the outlet temperature
v₂ = 0, the outlet velocity
From thermodynamic tables, obtain
h₂ = 163.76 Btu/(lbm-R)
p₂ = 40 psia, the exit pressure
Answer: 40 psia
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