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
yawa3891 [41]
3 years ago
13

A rigid 14-L vessel initially contains a mixture of liquid water and vapor at 100°C with 12.3 percent quality. The mixture is th

en heated until its temperature is 180°C. The final state is superheated water and the internal energy at this state should be obtained by interpolation. Calculate the heat transfer required for this process. Use data from the steam tables.
Engineering
2 answers:
tigry1 [53]3 years ago
7 0

Answer:

Q = 65.388 KJ

Explanation:

To calculate the heat required for the given process Q, we recall the energy balance equation.

Therefore, : Q = Δ U = m (u₂ - u₁) ..................equation (1)

We should note that there are no kinetic or potential energy change so the heat input in the system is converted only to internal energy.

Therefore, we will start the equation with the mass of the water (m) using given the initial percentage quality as x₁ = 0.123 and initial temperature t₁ = 100⁰c , we can them determine the initial specific volume v₁ of the mixture. For the calculation, we will also need the specific volume of liquid vₙ  = 0.001043m³/kg and water vapour (vₐ) = 1.6720m³/kg

Therefore, u₁ = vₙ + x₁ . ( vₐ - vₙ)

                   u₁ = 0.001043m³/kg + 0.123 . ( 1.6720m³/kg - 0.001043m³/kg)

                   u₁ = 0.2066m³/kg

Moving forward, the mass of the vapor can then be calculated using the given volume of tank V = 14 L but before the calculation, we need to convert the volume to from liters to m³.

Therefore, V = 14L . 1m² / 1000L = 0.014 m³

Hence, m = V / u₁

                 0.014m³ / 0.2066 m³/kg

              m = 0. 0677 kg

Also, the initial specific internal energy u₁ can be calculated using the given the initial given quality of x₁ , the specific internal energy of liquid water vₐ = 419.06 kj / kg and the specific internal energy of evaporation vₐₙ = 2087.0 kj/kg.

Therefore, u₁ = vₐ + x₁ . vₐₙ

                   u₁ = 419.06 kj / kg + 0.123  .  2087.0 kj/kg

                    u₁ = 675.76 kj/kg

For the final specific internal energy u₂, we first need to calculate the final quality of the mixture x₂ . The tank is rigid meaning the volume does not change and it is also closed meaning the mass does not change.from this, we can conclude the the specific volume also does not change during the process u₁ = u₂. This allows us to use the given final temperature T₂ = 180⁰c to determine the final quality x₂ of the mixture. for the calculation, we will also need the specific volume of liquid vₙ=0.001091m³/kg and vapor vₐ =  0.39248m³/kg

Hence, x₂ = u₂ - vₙ / uₐ

x₂ = 0.2066 m³/kg - 0.001091m³/kg / 0.39248m³/kg

x₂ = 0.524

Moving forward to calculate the final internal energy u₂, we have :

u₂ = vₙ + x₂ . vₙₐ

u₂ = 631.66 kj/kg + 0.524  . 1927.4 kj/kg

u₂ = 1641.62 kj/kg

We now return to equation (1) to plug in the values generated thus far

Q = m (u₂ - u₁)

0. 0677 kg ( 1641.62 kj/kg - 675.76 kj/kg)

Q = 65.388KJ

Troyanec [42]3 years ago
6 0

Answer:

98.13kJ

Explanation:

Given that;

The rigid 10-L vessel initially contains a mixture of liquid water & vapor at

T_1 =100^0C\\T_2 = 180^0C

We are to calculate the heat transfer required during the process by obtaining our data from the steam tables.

In order to do that, let start with our Energy Balance

So, Energy Balance for closed rigid tank system is given as:

\delta E_{system} = E_{in} - E_{out}

Since the K.E and P.E are insignificant;

∴ K.E = P.E = 0

Q_{in}= \delta U + W\\Q_{in} = m(u_2-u_1)+ W

Where;

m = mass flow rate of the mixture

(u_2-u_1) = corresponding change in the internal energy at state point 2 and 1

However, since we are informed that the vessel is rigid, then there is no work done in the system, then W turn out to be equal to zero .i,e

W = 0

we have our above equation re-written as:

Q_{in}= m (u_2-u_1)+0\\

Q_{in}= m(u_2-u_1)

We were told to obtain our data from the steam table, so were going to do just that

∴  At inlet temperature T_1 = 100^0C, the given quality of mixture of liquid water and vapor (x_1) = 123% = 0.123

Using the equation:

v_1 = v_f + x_1v_{fg}\\v_1 = v_f + x_1(v_g-v_f)

where;

v_1 = specific volume at state 1

v_f = specific volume of the liquid

v_g = specific volume of the liquid vapor mixture

The above data from the steam table is given as;

v_f  = 0.001043 m³/kg

v_g = 1.6720 m³/kg

so; we have

v_1 = 0.001043 + 0.123(1.6720-0.001043)

v_1 = 0.001043+0.123(1.670957)

v_1 =0.001043+0.205527711

v_1= 0.206570711m^3/kg

v_1=0.2065m^3/kg

At  T_1 = 100°C and x_1=0.123;

the following steam data from the tables were still obtained for the internal energy; which is given as:

Internal Energy (u_1) at the state 1

u_1= u_f + xu_{fg}

where;

specific internal energy of the liquid  (u_f)  = 419.06 kJ/kg

The specific internal energy of the liquid vapor mixture (u_{fg}) = 2087.0 kJ/kg

∴ since ; u_1= u_f + xu_{fg}

(u_1)  = 419.06 + (0.123 × 2087.0)

(u_1)  = 675.761 kJ/kg

As the tank is rigid, so as the volume which is kept constant:

v_2=v_1\\=0.2065 m^3/kg

Now, let take a look at when T_2 = 180^0C from the data in the steam tables

Specific volume of the liquid (v_f) = 0.00113 m³/kg

specific volume of the liquid vapor mixture (v_g) = 0.19384 m³/kg

The quality of the mixture at the final state 2 can be determined  by using the  equation shown below:

v_2=v_f+x_2v_{fg}

x_2=\frac{v_2-v_f}{v_{fg}}

x_2=\frac{v_2-v_f}{v_g-v_f}

x_2=\frac{0.2065-0.00113}{0.19384-0.00113}

x_2=\frac{0.20537}{0.19271}

    = 1.0657

From our usual steam table; we still obtained data for the Internal Energy when T_2=180^0C

Specific internal energy of the liquid (u_f) = 761.92 kJ/kg

Specific internal energy of the liquid vapor mixture u_{fg} = 1820.88 kJ/kg

Calculating the internal energy at finsl state point 2 ; we have:

u_2=u_f+u_{fg}

= 761.92 + (1.0657 × 1820.88)

= 761.92 + 1940.511816

= 2702.431816

u_2 ≅ 2702.43 kJ/kg

Furthermore, let us calculate the mass in the system; we have:

m= \frac{V_1}{v_1}

where V₁ = the volume 10 - L given by the system and v₁ = specific volume at state 1 as 0.2065

V₁ = the volume 10 - L = 10  × ( 0.001 m³/L)

v₁ = 0.2065

∴

mass (m) =  \frac{10(0.001m^3/L)}{0.2065}

= 0.04842 kg

Now, we gotten all we nee do calculate for the heat transfer that is required during the process:

Q_{in}= m(u_2-u_1)

Q_{in}= 0.04842(2702.43-675.761)

Q_{in}= 0.04842(2026.669)

Q_{in}= 98.13 kJ

Therefore, the heat transfer that is required during the process = 98.13 kJ

There you have it!, I hope this really helps alot!

You might be interested in
What is the mode of operation of a ramp digital voltimeter​
liberstina [14]

Answer:

The operating principle of a ramp type digital voltmeter is to measure the time that a linear ramp voltage takes to change from level of input voltage to zero voltage (or vice versa).

7 0
1 year ago
Identify the measurement shown in figure 7 and state in centimeters ​
Sav [38]

Answer:

1.3cm

Explanation:

the arrow is 3 lines past the 1 so it is 1.3cm

6 0
3 years ago
Some cars have an FCW, which stands for
Natalka [10]

Answer:

FCW in car stands for <em>Forward Collision Warning. </em>

<u>Explanation:</u>

The vehicle speed is monitored by <em>FCW system</em>, this is an advanced technology which indicates to the rear vehicle that a crash is going to happen if the vehicle gets close <em>because of speed</em>. This FCW systems monitor’s distance between the vehicles and speed of the vehicles.

<em>FCW system do not control the vehicle completely</em>. This system consists of sensors to detect stationary or slower-moving vehicles. A signal alerts the driver if the <em>distance between the vehicles is less</em> so that crash is being happened. It helps driver from crash by changing his route. Cars with this technology consists of audible alert.  

8 0
3 years ago
11) (10 points) A large valve is to be used to control water supply in large conduits. Model tests are to be done to determine h
IrinaVladis [17]

Answer:

7.94 ft^3/ s.

Explanation:

So, we are given that the '''model will be 1/6 scale (the modeled valve will be 1/6 the size of the prototype valve)'' and the prototype flow rate is to be 700 ft3 /s. Then, we are asked to look for or calculate or determine the value for the model flow rate.

Note that we are to use Reynolds scaling for the velocity as par the instruction from the question above.

Therefore; kp/ks = 1/6.

Hs= 700 ft3 /s and the formula for the Reynolds scaling => Hp/Hs = (kp/ks)^2.5.

Reynolds scaling==> Hp/ 700 = (1/6)^2.5.

= 7.94 ft^3/ s

7 0
3 years ago
Info security:
il63 [147K]

Answer:

True

Explanation:

Dual home host - it is referred to as the firewall that is incorporated with two or more networks. out of these two networks, one is assigned to the internal network and the other is for the network. The main purpose of the dual-homed host is to ensure that no Internet protocol traffic is induced between both the network.

The most simple example of a dual-homed host is a computing motherboard that is provided with two network interfaces.

7 0
3 years ago
Other questions:
  • If there are 16 signal combinations (states) and a baud rate (number of signals/second) of 8000/second, how many bps could I sen
    7·1 answer
  • I need solution for this question please<br>Select the right answer ​
    8·2 answers
  • Compared to arc welding, which of the following statements are true about<br> gas welding?
    13·1 answer
  • During an office party, an office worker claims that a can of cold beer on his table warmed up to 20oC by picking up energy from
    13·1 answer
  • Single point cutting tool removes material from a rotating work piece to generate a cylinder is called • Facing Tuming • Both 1
    6·1 answer
  • 1. Which type of fit implies that a piece will never fit? a. interference fit b. construction fit c. transition fit d. impeding
    8·1 answer
  • What are two reasons why Hunter edjucation is important?<br><br><br> 30 pts
    12·1 answer
  • 6.
    8·1 answer
  • Steam enters an adiabatic turbine at 6 MPa, 600°C, and 80 m/s and leaves at 50 kPa, 100°C, and 140 m/s. If the power output of t
    14·1 answer
  • A helicopter is hovering in a steady cross wind at a gross weight of 3,000 lb (1,360.8 kg). This helicopter has 275 hp (205 kW)
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!