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
KatRina [158]
3 years ago
11

A smoking lounge is to accommodate 19 heavy smokers. The minimum fresh air requirement for smoking lounges is specified to be 30

L/s per person (ASHRAE, Standard 62, 1989). Determine the minimum required flow rate of fresh air that needs to be supplied to the lounge and the diameter of the duct if the air velocity is not to exceed 8 m/s. (Round the final answers to two and three decimal places, respectively.) The minimum required flow rate of fresh air that needs to be supplied to the lounge is m3/s. The diameter of the duct if the air velocity is not to exceed 8 m/s is m.
Engineering
1 answer:
igor_vitrenko [27]3 years ago
7 0

Answer 1: minimum required flow rate of fresh air is 0.57 m^3/ses

Explanation: since the minimum requirement per person is 30 L/sec

Converting to m^3 it becomes

30/1000 = 0.03 m^3/sec

For 19 heavy smoker we will require

19 * 0.03 = 0.57m^3/sec

Answer 2: diameter of the duct will be 0.3m

Explanation: since flow rate is

Q =0.57m^3/sec

Also

Q = AV (continuity equation)

Where A is the duct area and V is the velocity of air flow in m/sec

0.57m^3/sec = A * 8m/sec

A = 0.57/8 = 0.071m^2

Area of the duct is that of a circle

A = 3.142 *(d^2 ÷4)

d^2 = (0.017 * 4)/3.142 = 0.09

d is square root of 0.09

d = 0.3m

You might be interested in
What is a problem that technology can help solve that problem?
Maslowich
Seeing what the other side of the world is doing right now
8 0
3 years ago
Read 2 more answers
What is the thermal efficiency of this regeneration cycle in terms of enthalpies and fractions of total flow?
irga5000 [103]

Answer:

\eta =\dfrac{(h_3-h_4)-(h_2-h_1)}{(h_3-h_5)}

Explanation:

generally regeneration of cycle is used in the case of gas turbine. due to regeneration efficiency of turbine is increased but there is no effect on the on the net work out put of turbine.Actually in regeneration net heta input is decreases that is why total efficiency  increase.

 Now from T-S diagram

    W_{net}=W_{out}-W_{in}

   W_{net}=(h_3-h_4)-(h_2-h_1)

  Q_{in}=h_3-h_5

  Due to generation (h_5-h_2) amount of energy has been saved.

  Q_{generation}=Q_{saved}

So efficiency of cycle \eta =\frac{W_{net}}{Q_{in}}

  \eta =\dfrac{(h_3-h_4)-(h_2-h_1)}{(h_3-h_5)}

Effectiveness of re-generator

  \varepsilon =\dfrac{(h_5-h_2)}{(h_4-h_2)}

So the efficiency of regenerative cycle

\eta =\dfrac{(h_3-h_4)-(h_2-h_1)}{(h_3-h_5)}

7 0
3 years ago
An ideal gas initially at 300 K and 1 bar undergoes a three-step mechanically reversible cycle in a closed system. In step 12, p
Veseljchak [2.6K]

Answer:

Ts =Ta E)- 300(

569.5 K

5

Q12-W12 = -4014.26

Mol

AU2s = Q23= 5601.55

Mol

AUs¡ = Ws¡ = -5601.55

Explanation:

A clear details for the question is also attached.

(b) The P,V and T for state 1,2 and 3

P =1 bar Ti = 300 K and Vi from ideal gas Vi=

10

24.9x10 m

=

P-5 bar

Due to step 12 is isothermal: T1 = T2= 300 K and

VVi24.9 x 10x-4.9 x 10-3 *

The values at 3 calclated by Uing step 3l Adiabatic process

B-P ()

Since step 23 is Isochoric: Va =Vs= 4.99 m* and 7=

14

Ps-1x(4.99 x 103

P-1x(29x 10)

9.49 barr

And Ts =Ta E)- 300(

569.5 K

5

(c) For step 12: Isothermal, Since AT = 0 then AH12 = AU12 = 0 and

Work done for Isotermal process define as

8.314 x 300 In =4014.26

Wi2= RTi ln

mol

And fromn first law of thermodynamic

AU12= W12 +Q12

Q12-W12 = -4014.26

Mol

F'or step 23 Isochoric: AV = 0 Since volume change is zero W23= 0 and

Alls = Cp(L3-12)=5 x 8.311 (569.5 - 300) = 7812.18-

AU23= C (13-72) =5 x 8.314 (569.3 - 300) = 5601.53

Inol

Now from first law of thermodynamic the Q23

AU2s = Q23= 5601.55

Mol

For step 3-1 Adiabatic: Since in this process no heat transfer occur Q31= 0

and

AH

C,(T -Ts)=x 8.314 (300- 569.5)= -7842.18

mol

AU=C, (T¡-T)= x 8.314 (300

-5601.55

569.5)

mol

Now from first law of thermodynamie the Ws1

J

mol

AUs¡ = Ws¡ = -5601.55

3 0
3 years ago
The cube measures 3.0-ft on all sides and has a density of 3.1 slugs/ft3. How much does it weigh?
kodGreya [7K]

Answer:

W = 2695.14 lb

Explanation:

given,

side of cube = 3 ft

density of the cube = 3.1 slugs/ft³

we know,

density = \dfrac{mass}{volume}

mass = density x volume

volume = 3³ = 27 ft³

mass =  3.1  x 27

    m = 83.7 slugs.

weight calculation

converting mass from slug to pound

weight of 1 slug is equal to 32.2 lb

now,

weight of the cube is equal to

  W = 83.7 slugs x 32.2 lb/slug

  W = 2695.14 lb

hence, weight is equal to W = 2695.14 lb

4 0
3 years ago
If a student doesn't major in Engineering as an undergraduate, They could still find a successful
34kurt

Answer:

True

Explanation:

It could either be true or false because you dont really have to be great at something just to do it, you could try new things too.

5 0
2 years ago
Read 2 more answers
Other questions:
  • Consider the following pulley system. A block of mass m is connected to a translational spring of stiffness k through a cable, w
    10·1 answer
  • You read a research study that concludes that the higher a student's self-esteem, the better he performs in school. This sort of
    5·1 answer
  • Find the inductive reactance per mile of a single-phase overhead transmission line operating at 60 Hz, given the conductors to b
    6·1 answer
  • Write a script (Program 2) to perform t he following matrix operations. Use output commands to clearly output each problem with
    15·1 answer
  • potential difference is the work done in moving a unit positive charge from one point to another in an electric field. State Tru
    12·1 answer
  • An intelligence signal is amplified by a 65% efficient amplifier before being combined with a 250W carrier to generate an AM sig
    5·1 answer
  • A rectangular bar has a edge crack at the bottom and is subjected to a pure bending moment. The crack length is a = 1 mm. The he
    14·1 answer
  • Type the correct answer in the box. Spell all words correctly.
    6·2 answers
  • Analyze the example of this band saw wheel and axle. The diameter of the wheel is 14 inches. The diameter of the axle that drive
    9·1 answer
  • Explain race condition..<br><br>don't spam..​
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!