Engineering, 12.03.2020 06:18 coopera1744

Refrigerant-134a at 400 psia has a specific volume of 0.1384 ft3/lbm. Determine the temperature of the refrigerant based on (a) the ideal-gas equation, (b) the generalized compressibility chart, and (c) the refrigerant tables.

Answers: 3

Show answers

Answers

Answer from: rosyjesus297

The temperature based on ideal gas is T = 526 R

The temperature based on compressibility chart is T = 694 R

The temperature based on refrigerant tables is T = 700 R

Explanation:

From the mathematical relation of an ideal gas we can define the temperature of the Refrigerant-134a as follows

$T = \frac{Pv}{R}$

Where is the pressure of the refrigerant and given as = 400 psia

v is the volume of the refrigerant and it is given as = 0.1384 ft^3/lbm

R is the gas constant and has a value of $0.1052\ psia \ \cdot ft^3/lbm \ \cdot R$ for Refrigerant-134a

Substituting values

$T = \frac{(400psia)(0.1384\ ft^3/lbm)}{0.1052 pais \cdot ft^3/lbm \cdot R}$

= 526 R

Considering the generalized compressibility chart

looking at table of molar mass, gas constants and critical-point properties.The temperature of Refrigerant-134a denoted by $T_{cr}$ is 673.6 R and the critical pressure of Refrigerant-134a is 588.7 psia

Mathematically the reduced pressure is

$P_R = \frac{P}{P_{cr}}$

substituting given and value obtained from table

$P_R = \frac{400psia}{588.7psia} =0.679$

The pseudo-reduced specific volume is Mathematically given as

$V_R = \frac{v_{actual}}{RT_{cr}/P_{cr}}$

$Substituting \ 588.7\ psia \ for \ P_{cr} \ 673.6\ R \ for \ T_{cr} \ 0.1052\ psia \ \cdot \ ft^3 /lbm \cdot R\\\\ \ for \ R \ 0.1384ft^3/lbm \ for \ v_{actual}$

$V_R = \frac{0.1384}{(0.1052)(673.6)/588.7} = \frac{(0.1384)(588.7)}{(0.1052)(673.6)} =1.15$

Now the value of pseudo-reduced specific volume and reduced pressure would gives us a pointer to select the correct value of reduced temperature( T_R ) from the generalized compressibility chart

and this is 1.03 for T_R

Hence the temperature of the Refrigerant-134a

$T = T_R T_{cr}$

Substituting values

T = (1.03)(673.6 R)

$= 694\ R$

Considering the refrigerant tables

looking at the table of super-heated Refrigerant-134a the temperature for a pressure of 400 psia and

specific volume of 0.1384ft^3/lbm is 240°F

Converting to Rankine scales we add 460

$T = 240 +460 = 700\ R$

Answer from: Quest

the clapeyron equation (also called the clausius-clapeyron equation) relates the slope of a reaction line on a phase diagram to fundamental thermodynamic properties.

explanation:

Answer from: Quest

answer:

true

explanation:

Another question on Engineering

Engineering, 04.07.2019 18:10

Steel is coated with a thin layer of ceramic to protect against corrosion. what do you expect to happen to the coating when the temperature of the steel is increased significantly? explain.

Answers: 1

Answer

Engineering, 06.07.2019 02:30

A75mm diameter shaft is supported in a journal bearing 75mm long with a diametral clearance of 0. 1mm. it supports a radial load of 1000 n and is lubricated with sae 50 oil at 70°c. find the friction torque and the power loss when the crankshaft rotates at 2900 rev/min.

Answers: 1

Answer

Engineering, 06.07.2019 03:20

What is the maximum height from which a mass of 30 kg can fall on to a flange on the lower end of a vertical rod of length 1.0 m and diameter 20 mm, the upper end being rigidly fixed, if the stress in the rod is not to exceed 80 mpa? the tensile modulus of the rod is 200 gpa.

Answers: 3

Answer

Engineering, 06.07.2019 04:10

Agas mixture with a compostion of 55 methane, 30% propane, and 15 butane by volume) is compressed from 1 bar and 25°c to 9bar in a compressor with an isentropic efficiency of 85%. the environment has a temperature of to25 c. determine (a) the exit temperature of the mixture (b) the specific work required to run the compressor (c) the specific entropy generation of the process (d) the specific exergy destruction of the process (e) the second law efficiency of the compressor

Answers: 3

Answer

You know the right answer?

Refrigerant-134a at 400 psia has a specific volume of 0.1384 ft3/lbm. Determine the temperature of t...

Questions