Vapour Compression Heat Cycle

Question 1

Work consumed by the system

Answer 1

negative

Question 2

Work produced by the system

Answer 2

positive

Question 3

First law of thermodynamics for a closed system

Answer 3

sum of heat = sum of work + change in energy

Question 4

First law of thermodynamics for an open system

Answer 4

Qdot = Wdot + Mdot ( (h2-h1) +(0.5c2^2 - c1^2) + g(z2 -z1))

Question 5

Enthalpy equation

Answer 5

H = U + pV

Question 6

Ideal gas equation

Answer 6

PV = mRT

Question 7

Specific heat definition

Answer 7

the energy required to raise the temperature of a unit mass of a substance by one degree

Question 8

Efficiency equation

Answer 8

net work output / gross heat input

Question 9

ratio of specific heats is denoted by which greek letter

Answer 9

gamma

cp/cv

Question 10

what are the two variations of specific heat and their equations

Answer 10

c p = (dh/dT) p

c v =(du/dT) v

Question 11

what are the two perfect gas equations

Answer 11

u = cvT
h = cpT

Question 12

isentropic

Answer 12

constant entropy

Question 13

What is the equation relating COP of a heat pump and refridgerator?

Answer 13

COPhp = 1 + COPref

Question 14

What is the flow rate equation?

Answer 14

mdot = power kW / heat (q)

Question 15

What does a reversible process mean?

Answer 15

The process wherein the quantity of heat transferred is directly proportional to the
systems entropy change.