Defination of rolling

A Carnot refrigeration cycle absorbs heat at -12 °C and rejects it at 40 °C. a)-Calculate the coefficient of performance of this

tresset_1 [31]

Answer:

a)COP=5.01

b) $W_{in}=2.998$ KW

c)COP=6.01

d) $Q_R=17.99 KW$

Explanation:

Given

$T_L$ = -12°C, $T_H$ =40°C

For refrigeration

We know that Carnot cycle is an ideal cycle that have all reversible process.

So COP of refrigeration is given as follows

$COP=\dfrac{T_L}{T_H-T_L}$ ,T in Kelvin.

$COP=\dfrac{261}{313-261}$

a)COP=5.01

Given that refrigeration effect= 15 KW

We know that $COP=\dfrac{RE}{W_{in}}$

RE is the refrigeration effect

So

5.01= $\dfrac{15}{W_{in}}$

b) $W_{in}=2.998$ KW

For heat pump

So COP of heat pump is given as follows

$COP=\dfrac{T_h}{T_H-T_L}$ ,T in Kelvin.

$COP=\dfrac{313}{313-261}$

c)COP=6.01

In heat pump

Heat rejection at high temperature=heat absorb at low temperature+work in put

$Q_R=Q_A+W_{in}$

Given that $Q_A=15$ KW

We know that $COP=\dfrac{Q_R}{W_{in}}$

$COP=\dfrac{Q_R}{Q_R-Q_A}$

$6.01=\dfrac{Q_R}{Q_R-15}$

d) $Q_R=17.99 KW$

5 0

3 years ago

12.50 An air conditioner operating at steady state takes in moist air at 28°C, 1 bar, and 70% relative humidity. The moist air f

Mandarinka [93]

Answer:

Hey smith please see attachments for answer:

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The attachments will provide you a detailed answer

Explanation:

8 0

3 years ago

A 2-mm-diameter electrical wire is insulated by a 2-mm-thick rubberized sheath (k = 0.13 W/m K), and the wire/sheath interface i

Semmy [17]

Answer:

maximum allowable electrical power=4.51W/m

critical radius of the insulation=13mm

Explanation:

Hello!

To solve this heat transfer problem we must initially draw the wire and interpret the whole problem (see attached image)

Subsequently, consider the heat transfer equation from the internal part of the tube to the external air, taking into account the resistance by convection, and conduction as shown in the attached image

to find the critical insulation radius we must divide the conductivity of the material by the external convective coefficient

$r=\frac{k}{h} =\frac{0.13}{10}=0.013m=13mm$

3 0

2 years ago

joe is an exceptional systems engineer who hopes to work at the techtonic group. he is handicapped and uses a wheelchair. techto

ASHA 777 [7]

The HR department should install wheelchair ramps and widen the doorways as they don't want to loose an exceptional systems engineer who hopes to work at the techtonic group.

What is a wheelchair ramps?

A wheelchair ramp is an inclined plane that can be installed in addition to or instead of stairs. Ramps make it easier for wheelchair users, as well as people pushing strollers, carts, or other wheeled objects, to enter a building.

The Americans with Disabilities Act requires wheelchair ramps (or other ways for wheelchair users to access a building, such as a wheelchair lift) in new construction for public accommodations in the United States.

A wheelchair ramp can be fixed, semi-fixed, or portable. Permanent ramps are intended to be bolted or otherwise attached to the ground. Semi-permanent ramps are commonly used in the short term and rest on top of the ground or concrete pad.

To know more about wheelchair ramps, visit: brainly.com/question/17395685

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5 0

1 year ago

A tubular reactor has been sized to obtain 98% conversion and to process 0.03 m^3/s. The reaction is a first-order irreversible

Zolol [24]

Answer:

The conversion in the real reactor is = 88%

Explanation:

conversion = 98% = 0.98

process rate = 0.03 m^3/s

length of reactor = 3 m