2.1 A 2000-kg car accelerates from 20 to 60 km/h on an uphill road. The car travels 120 m and the slope of the road
from the horizontal is 25o. Determine the work done by the engine.
Approach:
Apply the first law choosing the car to be the system
under co
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
1. WORK (SECTION 2.8)
A. DEFINITION OF WORK
B. TYPES OF WORK COMPRESSION/EXPANSION, ELECTRIC, SHAFT
2. KINETIC ENERGY AND WORK (SECTION 2.9)
3. POTENTIAL ENERGY AND WORK (SECTION 2.10)
4. ENTHALPY A
Lecture Notes Set 3
TF1 Smith
Related Text Material: Sections 2.8 2.10
Relationship between heat and work:
Work produces the same effect on a system (raising its
temperature) as can heat.
Is there some relationship between
mechanical work
and heat?
Joules
Lecture Notes Set 4
TF1-Smith
(Related Text Material: Section 2.6)
Ideal Gases
We have already introduced three thermodynamic properties:
In particular we are interested in
the relationship among
substance
,
,
and
for a pure
also the phases of pure subs
Lecture Notes Set 1
TF1 Smith
Related Text Material: Sections 1.1-1.5
ENGR-2250 Thermal and Fluids Engineering I (4 cr. hr.)
Introductory Notes
Multidisciplinary Engineering course
Intended for students who will have no other courses in this area
Contro
Lecture Notes Set 5
TF1-Smith
(Related Text Material: Sections 2.11; 2.13)
First Law Continued:
Now consider the work done in a cyclic process
Piston-cylinder device
undergoing p-V work
p
V
Process 1a2:
Process 2b1:
Now consider Process 1a2b1:
Since (1) a
Lecture Notes Set 7
TF1-Smith
(Related Text Material: Sections 3.1 3.5, 3.7)
First Law and Heat Transfer
Elementary consideration of heat transfer rates:
In the absence of work interactions, the first law may be written
as
or in a rate form as
Surface ene
Lecture Notes Set 2
TF1 Smith
Related Text Material: Sections 2.1-2.4; 2.7 2.10
Energy
Forms of Energy
E (kJ)
Alt. units:
e (kJ/kg) =
Total energy consists of several different parts:
Thermodynamics only tells us about energy
zero is quite arbitrary
Macro
This table lists the ASCII characters and their decimal, octal and hexadecimal numbers. Characters that appear as names in
parentheses [e.g., (nl)] are non-printing characters.
ASCII Name
nul
bel
bs
ht
np (next page)
Description
null byte
bell character
b
MANE 4010 Thermal and Fluids Engineering II
Spring 2016 (Section 2 Only)
Homework Assignment No. 3
Due Date: Friday, February 19
For the convenience of your instructor and the graders, please use the following format:
1.
Staple (preferred) or clip but do
Lecture Notes Set 6
TF1-Smith
(Related Text Material: Sections 2.11 2.12; 2.14)
Specific Heats of Other Materials
We have already learned that
du = cvdT
for any process
involving an ideal gas
In general, it can be shown that
for any material, any process
ENGR-2250 Thermal and Fluids Engineering I
Fall 2016 (Sections 2 and 3 Only)
Homework Assignment No. 3
Due Date: Friday, September 23, 2016
Solution
1.
A gas is compressed polytropically, that is according to a relationship p Vn = C, where C and n are con
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
RECAP
1. RELATION BETWEEN AND (SECTION 2.11 )
2. POLYTROPIC PROCESS (SECTION 2.12)
3. FIRST LAW AS RATE EQUATION (SECTIONS 2.13 & 3.1)
RECAP
Quasi-equilibrium Process A process passing through a suc
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
Properties of Pure Substances (Sections 5.1 to 5.3)
Phase Diagram T-v, P-v and P-T Plots
Properties in the Two-Phase Region
Phase Diagram What happens when Waters heated?
Whats a Pure Substance:
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
1. RECAP
2. FUNDAMENTAL THERMODYNAMIC PROPERTIES
SECTION 2.5
3. UNIT SYSTEM
SECTION 2.7
4. INTERNAL ENERGY & SPECIFIC HEAT OF IDEAL LIQUIDS AND SOLIDS
SECTIONS 2.3-2.4
5. IDEAL GASES & IDEAL GAS LAW
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
Bernoullis Equation (SECTION 4.6)
Flow Measurement
Stagnation Tube
Venturi Meter
The Bernoullis Equation
The first law for an open system is
dEcv
Vi 2
Ve 2
Qcv Wcv mi hi
gzi me he
gze
dt
2
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
1. RESISTANCE ANALOGY FOR RADIATION (SECTION 3.7)
2. LUMPED SYSTEM APPROXIMATION (SECTION 3.6)
1. RESISTANCE ANALOGY FOR RADIATION
The net radiative heat transfer between a small gray body and a lar
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
Open and Closed Systems (SECTION 4.3)
Conservation of Mass (SECTION 4.4)
Conservation of Energy (SECTION 4.5)
Open and Closed Systems:
Open System mass crosses boundary
Closed System no mass cros
THERMAL FLUIDS ENGINEERING 1
ENGR 2250
OBJECTIVES TODAY:
Conservation of Linear Momentum in Open Systems
(Section 4.8)
Derivation of Momentum Equation
Pressure, Gravitational and External Forces in the
Momentum Equation
Conservation of Linear Momentum
ENGR-2250 Thermal and Fluids Engineering I
Fall 2016 (Sections 2 and 3 Only)
Homework Assignment No. 2
Due Date: Friday, September 16, 2016
Solution
1.
As shown in the figure, an inclined tube manometer is used to
measure the pressure of the gas within th
ENGR-2250 Thermal and Fluids Engineering I
Fall 2016 (Sections 2 and 3 Only)
Homework Assignment No. 1
Due Date: Friday, September 9, 2016
Solution
1.
Referring to the figure, water circulates between a storage
tank and a solar collector. Heated water fro