1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
umka21 [38]
2 years ago
15

Refrigerant-134a enters the expansion valve of a refrigeration system at 120 psia as a saturated liquid and leaves at 20 psia. D

etermine the temperature and internal energy changes across the valve. Use data from the steam tables.
Engineering
1 answer:
Shkiper50 [21]2 years ago
5 0

Solution :

$P_1 = 120 \ psia$

$P_2 = 20 \ psia$

Using the data table for refrigerant-134a at P = 120 psia

$h_1=h_f=40.8365 \ Btu/lbm$

$u_1=u_f=40.5485 \ Btu/lbm$

$T_{sat}=87.745^\circ  F$

∴ $h_2=h_1=40.8365 \ Btu/lbm$

For pressure, P = 20 psia

$h_{2f} = 11.445 \ Btu/lbm$

$h_{2g} = 102.73 \ Btu/lbm$

$u_{2f} = 11.401 \ Btu/lbm$

$u_{2g} = 94.3 \ Btu/lbm$

$T_2=T_{sat}=-2.43^\circ  F$

Change in temperature, $\Delta T = T_2-T_1$

                                         $\Delta T = -2.43-87.745$

                                           $\Delta T=-90.175^\circ  F$

Now we find the quality,

$h_2=h_f+x_2(h_g-h_f)$

$40.8365=11.445+x_2(91.282)$

$x_2=0.32198$

The final energy,

$u_2=u_f+x_2.u_{fg}$

   $=11.401+0.32198(82.898)$

   $=38.09297 \ Btu/lbm$

Change in internal energy  

$\Delta u= u_2-u_1$

   = 38.09297-40.5485

  = -2.4556        

You might be interested in
Integer to Float Conversion All labs must be done during lab time. Each labs worth 10 points The lab can be hand in next day wit
andrew-mc [135]

Answer:

Code explained below

Explanation:

.data

msg1: .asciiz "Please input a temperature in celsius: "

msg2: .asciiz "The temperature in Fahrenheit is: => "

num: .float 0.0

.text

main:

#print the msg1

li $v0, 4

la $a0, msg1

syscall

#read the float value from user

li $v0,6 #read float syscall value is $v0

syscall #read value stored in $f0

#formula for celsius to fahrenheit is

#(temperature(C)* 9/5)+32

#li.s means load immediate float

#copy value 9.0 to $f2

li.s $f2,9.0  

#copy value 5.0 to $f3

li.s $f3,5.0

# following instructions performs: 9/5

#div.s - division of two float numbers

#divide $f2 and f3.Result will stores in $f1

div.s $f1,$f2,$f3

#following instruction performs: temperature(C) * (9/5)

#multiple $f1 and $f0.Result stored in $f1

mul.s $f1,$f1,$f0

#copy value 32 to $f4

li.s $f4,32.0

#following instruction performs: (temperature(C) * (9/5))+32

#add $f1 and $f4.Result stores in $f1

add.s $f1,$f1,$f4

#store float from $f1 to num

s.s $f1,num

#print the msg2

li $v0, 4 #print string syscall value is 4

la $a0, msg2 #copy address of msg2 to $a0

#print the float

syscall

li $v0,2 #print float syscall value is 2

l.s $f12,num #load value in num to $f12

syscall

#terminate the program

li $v0, 10 #terminate the program syscall value is 10

syscall

4 0
3 years ago
A spherical gas container made of steel has a(n) 17-ft outer diameter and a wall thickness of 0.375 in. Knowing that the interna
Arte-miy333 [17]

Answer:

Maximum Normal Stress σ = 8.16 Ksi

Maximum Shearing Stress τ = 4.08 Ksi

Explanation:

Outer diameter of spherical container D = 17 ft

Convert feet to inches D = 17 x 12 in = 204 inches

Wall thickness t = 0.375 in

Internal Pressure P = 60 Psi

Maximum Normal Stress σ = PD / 4t

σ = PD / 4t

σ = (60 psi x 204 in) / (4 x 0.375 in)

σ = 12,240 / 1.5

σ = 8,160 P/in

σ = 8.16 Ksi

Maximum Shearing Stress τ = PD / 8t

τ = PD / 8t

τ = (60 psi x 204 in) / (8 x 0.375 in)

τ = 12,240 / 3

τ = 4,080 P/in

τ = 4.08 Ksi

7 0
3 years ago
When Ontario
Marat540 [252]

Answer:

Explanation:

This will be possible when setting them up in summer with a certain quantity of sag, they have already know that the cables won't be able to sag any further because of the heat. During winter, when the cables contract because of the cold weather, the sag will therefore be reduced, but much tension will not be put on the cables.

4 0
2 years ago
How are industries related to systems
REY [17]

Answer:

The industrial systems of the future are seen as complex systems, composed of vast numbers of devices, interacting with each other and with enterprise systems continuously.

summary:

they are related because they ARE a system. well, a type.

hope this helps!! :)

7 0
2 years ago
In an international film festival, a penal of 11 judges is formed to judge the best film. At
Julli [10]

Answer:

International Film Festival

Judging the best best film:

a. The probability that out of five judges (random sample),  three are in favor of film FA is:

= 33%.

b. The demerits of classical probability are:

1. Classical probability can only be used with events that have definite numbers of possible outcomes.  

2. Classical probability can only handle events where each outcome is equally likely.

3. Classical probability is based on the assumption of linear relationship (which is not always true in real life) between the latent variable and observed scores.

Explanation:

a) Number of judges = 11

Number of judges in favor of FA film = 6

Number of judges in favor of FB film = 5

Probability of judges in favor of FA film = 6/11

Probability of judges in favor of FB film = 5/11

Random sample of judges = 5

Probability that out of five judges, three are in favor of film FA = 3/5 * 6/11

= 18/55

= 33%

b) Classical probability is the simple probability showing that each event has equal chance of happening.  It can be contrasted with empirical probability that is obtained from experiments.

7 0
3 years ago
Other questions:
  • Under conditions for which the same roojm temperature is mainteined bt a heating or cooling system, it is not uncommon for a per
    10·1 answer
  • What is Back EMF? How does it limits the speed of a permanent magnet DC?
    10·1 answer
  • Write Python expressions using s1, s2, and s3 and operators and * that evaluate to: (a) 'ant bat cod'
    14·1 answer
  • The conditions at the beginning of compression in an Otto engine operating on hot-air standard with k=1.35 and 101.325 kPa, 0.05
    10·1 answer
  • Why is data driven analytics of interest to companies?
    9·1 answer
  • If you have 300 skittles in a bag and you need to have 28 percent yellow. How many yellow skittles would you have to make a mini
    11·1 answer
  • Cual es la definición de la distribución de las instalaciones?
    13·2 answers
  • Consider 2 hosts, Host A and Host B, transmitting a large file to a Server C over a bottleneck link with a rate of R kbps.
    12·1 answer
  • For RTK to work, what do we need besides two or more receivers collecting data from a sufficient number of satellites simultaneo
    11·1 answer
  • Whats the purpose of the keyway
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!