|
oMarch 1988
March 1988
Floppy disc included with this
item has been shelved separately.
Consult LUIS or ask circulation
staff for assistance.
Circular 772
GREENHOUSE
Estimation of Greenhouse Heat Losses
COMPUTER SERIES I
P.B. Panagakis, F.S. Zazueta and R.A. Bucklin
Centra! Science
Library
JAN 30 1990
I' ty of Florida
W m
PFUS
101 active Extension Service / Institute of Food and Agricultural Sciences / University of Florida / John T. Woete, Dean
F636c
772
codebk
GREENHOUSE
Estimation of Greenhouse Heat Losses
P.B. Panagakis, F.S. Zazueta and R.A. Bucklin*
* Graduate Assistant, Associate and Assistant Professors
respectively, Department of Agricultural Engineering Institute
of Food and Agricultural Sciences, University of Florida,
Gainesville 32611.
Estimation of Greenhouse Heat Losses
P.B. Panagakis, F.S. Zazueta and R.A. Bucklin
Introduction
Energy expenditure for greenhouse heating becomes critical
because of the instability in prices and availability of fossil
fuels. Heating represents the largest energy expense in
traditional greenhouse operations and the required amount of
money depends on the climate, the condition of the structure and
the crops grown.
The first step in an energy conservation program in
greenhouses, is to make an estimate of the heat losses from the
entire structure. If the estimated losses are large, conserva-
tion techniques can be used to reduce them.
This program, GREENHOUSE, allows the computation of
conduction, infiltration and total heat losses from the following
types of greenhouses:
1) Gable or curved greenhouses using one material for the
wall.
2) Gable or curved greenhouses using different materials
for the lower and upper wall.
3) Quonset greenhouses.
Input Data
The required input data vary slightly with the type of
greenhouse for which the heat losses are being estimated. For
each one of the three types mentioned above the input data are as
follows
1) Gable/curved greenhouse using a single material for the wall.
The required data to estimate the heat losses in this type
of greenhouse (Figure 1) are:
1.1) Wall height (H): This is the height of the greenhouse
wall in feet.
1.2) House width (W): This is the width of the greenhouse
in feet.
1.3) House length (L): This is the length of the greenhouse
in feet.
1.4) Rafter length (R): This is the length of the rafter in
feet.
1.5) Gable height (G): This the height of the gable in
feet.
1.6) U factor of single material wall: This is the heat
transfer coefficient of the wall's material in
BTU/hr.F ft2. Values of this coefficient for typical
materials are shown in Table 1.
1.7) U factor of rafter material: This is the heat transfer
coefficient of the rafter's material in BTU/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
1.8) U factor of roof material: This is the heat transfer
coefficient of the roof's material in BTU/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
1.9) U factor of the perimeter: .This is the heat transfer
coefficient of the perimeter in BTU/hr F ft. Values of
this coefficient are shown in Table 1.
1.10) Number of individual bays: This is the number of
bays that make up the greenhouse.
1.11) Number of air exchanges per hour: This is the number
of times that the volume of air in the greenhouse is
replaced per hour. Typical values can be seen in
Table 2.
1.12) Temperature difference: This is the difference between
the nightime desired inside temperature and the minimum
expected outside temperature. This value is given in
degrees Fahrenheit.
2) Gable/curved greenhouse using different material for the
lower and upper wall.
The required data to estimate the heat losses in this type
of greenhouse (Figure 2) are:
2.1) Wall height (H): This is the height of the greenhouse
wall in feet.
2.2) Lower wall height (B): This is the height of the lower
wall in feet.
2.3) Upper wall height (A): This is the height of the upper
wall in feet.
2.4) House width (W): This is the width of the greenhouse
in feet.
2.5) House length (L): This is the length of the greenhouse
in feet.
2.6) Rafter length (R): This is the length of the rafter in
feet.
2.7) Gable height (G): This is the height of the gable in
feet.
2.8) U factor of lower wall material: This is the heat
transfer coefficient of the lower wall's material in
BTU/hr F ft2. Values of this coefficient for typical
materials are shown in Table 1.
2.9) U factor of upper wall material: This is the heat
transfer coefficient of the upper wall's material in
BTU/hr F ft2. Values of this coefficient for typical
materials are shown in Table 1.
2.10) U factor of rafter material: This is the heat transfer
coefficient of the rafter's material in BTU/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
2.11) U factor of roof material: This is the heat transfer
coefficient of the roof's material in BTU/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
2.12) U factor of the perimeter: This is the heat transfer
coefficient of the perimeter in BTU/hr F ft. Values of
this coefficient are shown in Table 1.
2.13) Number of individual bays: This is the number of bays
that make up the greenhouse.
2.14) Number of air exchanges per hour: This is the number
of times that the volume of air in the greenhouse is
replaced per hour. Typical values can be seen in
Table 2.
2.15) Temperature difference: This is the difference between
the nightime inside desired temperature and the minimum
expected outside temperature. This value is given in
degrees Fahrenheit.
3) Quonset greenhouse.
The required data to estimate the heat losses in this type
of greenhouse (Figure 3) are:
3.1) House width (W): This is the width of the greenhouse
in feet.
3.2) House length (L): This is the length of the greenhouse
in feet.
3.3) Rafter length (R): This is the length of the rafter in
feet.
3.4) Gable height (G): This is the height of the gable in
feet.
3.5) U factor of rafter material: This is the heat transfer
coeffici-ent of the rafter's material in BTU/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
3.6) U factor of roof material: This is the heat transfer
coefficient of the roof's material in BTu/hr F ft2.
Values of this coefficient for typical materials are
shown in Table 1.
3.7) U factor of the perimeter: This is the heat transfer
coefficient of the perimeter material in BTU/hr F ft2.
Values of this coefficient are shown in Table 1.
3.8) Number of air exchanges per hour: This is the number
of times that the volume of air in the greenhouse is
replaced per hour. Typical values can be seen in
Table 2.
3.9) Temperature difference: This is the difference between
the nightime inside desired temperature and the minimum
expected outside temperature. This value is given in
degrees Fahrenheit.
Output
The results of the program consist of the computed values
of conduction, infiltration, and total heat losses. Results are
expressed in BTU/hr.
Conduction may be viewed as "the transfer of energy from the
more energetic to the less energetic particles of a substance due
to interaction between the particles" (Incropera and DeWitt,
1981).
In the case of the greenhouse conduction heat losses are due
to the difference between inside and outside temperature. These
losses are proportional to the surface area of the greenhouse,
the heat transfer coefficient of the greenhouse material and the
perimeter, and the difference between inside and outside
temperature.
Infiltration is the exchange of inside and outside air. The
rate of infiltration depends upon the direction and the speed of
the wind, the difference between inside and outside temperature,
and the type and quality of the greenhouse construction.
Technical Notes
A practical method to compute the total heat losses from a
greenhouse is to add the conduction and infiltration heat losses.
Conduction heat losses can be computed using the conduction
heat transfer equation.
Qc = A U Dt (1)
where
Qc = Heat transfer through the material in BTU/hr,
A = Exposed surface area in ft2,
U = Heat transmission coefficient in BTU/hr F ft2,
Dt = Temperature difference between inside and outside
in degrees Fahrenheit.
Infiltration heat losses can be computed using the formula:
Qa = 0.02 Dt V Na (2)
where
Qa = Air infiltration heat losses in BTU/hr,
Dt = Temperature difference between inside and outside
in degrees Fahrenheit,
V = Volume of the greenhouse in ft3, and
Na = Number of air volumes exchanged per hour.
Total heat losses from the greenhouse are obtained by
summing conduction and infiltration heat losses.
Qt = Qc + Qa (3)
where
Qt = total heat losses in BTU/hr.
Sample Run
The following is a step-by-step example of how to use this
software to estimate the heat losses from different greenhouse
types.
1. To run the program place the disk that contains the
GREENHOUSE.COM file in Drive A.
2. Type GREENHOUSE . If the banner shown in CRT 1
is displayed the program has loaded successfully. If the message
"Bad command or file name" is displayed you do not have the disk
with the GREENHOUSE program in Drive A (default drive).
3. After a while the screen will display a mask as is shown
in CRT 2. At the point where the cursor is blinking enter the
selection.
4a) If the entered selection is 1, the screen will show an
input/output mask as shown in CRT 3. Enter the corresponding
data on each of the fields (see Appendix A) that are shown in
Table A.
Table A
Wall Height: 8.0 ft
House Width: 40.0 ft
House Length: 96.0 ft
Rafter Length: 22.4 ft
Gable Height: 10.0 ft
U Factor Of Single Material Wall: 1.1 BTU/hr. F ft2
U Factor Of Rafter Material: 1.1 BTU/hr. F ft2
U Factor Of Roof Material: 1.1 BTU/hr. F ft2
U Factor Of Perimeter: 0.8 BTU/hr. F ft
Number Of Individual Houses: 1
Number Of Air Exchanges Per Hour: 1.5
Temperature Difference: 60.0 F
-----------------------------------------------------
Once the last datum has been entered press the key.
A mask as shown in CRT 4 will be displayed.
i) Typing Y the computations will be performed and a mask
as shown in CRT will be displayed on the screen. At the point
where the cursor is blinking you can enter Y or N. Entering Y
the MAIN MENU will be displayed. Entering N sends the cursor to
the first input field and new data can be entered.
ii) Typing N sends the cursor to the last input field.
4b) If the entered selection is 2, the screen will show an
input/output mask as shown in CRT 6. Enter the corresponding
data on each of the fields (see Appendix A) that are shown in
Table B.
Once the last datum has been entered and there are no
mistakes press the key. A mask as shown in CRT 7 will be
displayed.
i) Typing N the computations will be performed and a mask
as shown in CRT 8 will be displayed on the screen. At
the point where the cursor is blinking you can enter Y
or N. Entering Y the MAIN MENU will be displayed.
Entering N sends the cursor to the first input field
and new dTta can be entered.
ii) Typing N sends the cursor to the last input field.
4c) If the entered selection is 3, the screen will show an
input/output mask as shown in CRT 9. Enter the corresponding
data on each of the fields (see Appendix A) that are shown in
Table C.
Once the last datum has been entered and there are no
mistakes press the key. A mask as shown in CRT 10 will be
displayed.
i) Typing Y the computations will be performed and a mask
as shown in CRT 11 will be displayed on the screen. At
the point where the cursor is blinking you can enter Y
or N. Entering Y the MAIN MENU will be displayed.
Entering N sends the cursor to the first input field
and new data can be entered.
ii) Typing N sends the cursor to the last input field.
Table B
Wall Height: 8.0 ft
Lower Wall Height: 2.0 ft
Upper Wall Height: 6.0 ft
House Width: 40.0 ft
House Length: 96.0 ft
Rafter Length: 22.4 ft
Gable Height: 10.0 ft
U Factor Of Lower Wall Material: 1.1 BTU/hr. F ft2
U Factor Of Upper Wall Material: 1.1 BTU/hr. F ft2
U Factor Of Rafter Material: 1.1 BTU/hr. F ft2
U Factor Of Roof Material: 1.1 BTU/hr. F ft2
U Factor Of Perimeter: 0.8 BTU/hr. F ft
Number Of Individual Houses: 1
Number Of Air Exchanges Per Hour: 1.5
Temperature Difference: 60.0 F
Table C
Wall Height: 8.0 ft
House Width: 40.0 ft
House Length: 96.0 ft
Rafter Length: 44.9 ft
Gable Height: 3.0 ft
U Factor of Lower Wall Material: 1.1 BTU/hr. F ft2
U Factor of Upper Wall Material: 1.1 BTU/hr. F ft2
U Factor Of Roof Material: 1.1 BTU/hr. F ft2
U Factor Of Perimeter: 0.8 BTU/hr. F ft
Number Of Individual Houses: 1
Number Of Air Exchanges Per Hour: 1.5
Temperature Difference: 60.0 F
4d) If the entered selection is 4, the screen will show an
input/output mask as shown in CRT 12. Enter the corresponding
data on each of the fields (see Appendix A) that are shown in
Table D.
Once the last datum has been entered and there are no
mistakes press the key. A mask as shown in CRT 13 will be
displayed.
i) Typing Y the computations will be performed and a mask
as shown in CRT 14 will be displayed on the screen. At the point
where the cursor is blinking you can enter Y or N. Entering Y
the MAIN MENU will be displayed. Entering N sends the cursor to
the first input field and new data can be entered.
ii) Typing N sends the cursor to the last input field.
------------------------------------------------------
Table D
Wall Height: 8.0 ft
Lower Wall Height: 2.0 ft
Upper Wall Height: 6.0 ft
House Width: 40.0 ft
House Length: 96.0 ft
Rafter Length: 44.9 ft
Gable Height: 3.0 ft
U Factor Of Lower Wall Material: 1.1 BTU/hr. F ft2
U Factor Of Upper Wall Material: 1.1 BTU/hr. F ft2
U Factor Of Rafter Material: 1.1 BTU/hr. F ft2
U Factor Of Roof Material: 1.1 BTU/hr. F ft2
U Factor Of Perimeter: 0.8 BTU/hr. F ft
Number Of Individual Houses: 1
Number Of Air Exchanges Per Hour: 1.5
Temperature Difference: 60.0 F
----------------------------------------------------
4e) If the entered selection is 5, the screen will show an
input/output mask as shown in CRT 15. Enter the corresponding
data on each of the fields (see Appendix A) that are shown in
Table E.
------------------------------------------------------
Table E
------------------------------------------------------
House Width: 40.0 ft
House Length: 96.0 ft
Rafter Length: 49.7 ft
Gable Height: 10.0 ft
U Factor Of Rafter Material: 1.1 BTU/hr. F ft2
U Factor Of Roof Material: 1.1 BTU/hr. F ft2
U Factor Of Perimeter: 0.8 BTU/hr. F ft
Number Of Air Exchanges Per Hour: 1.5
Temperature Difference: 60.0 F
-------------------------------------------
Once the last datum has been entered and there are no
mistakes press the key. A mask as shown in CRT 16 will be
displayed.
i) Typing Y the computations will be performed and a mask
as shown in CRT 17 will be displayed on the screen. At the point
where the cursor is blinking you can enter Y or N. Entering Y
the MAIN MENU will be displayed. Entering N sends the cursor to
the first input field and new data can be entered.
ii) Typing N sends the cursor to the last input field.
4f) If the entered selection is 6, the display will be
cleared and control will be returned to the Operating System.
Appendix A
This appendix contains a brief description of how to enter
and edit data.
i. The fields where you can enter your data are denoted
with blue color.
ii. Within the field you can move either to the right using
the <-- > key or to the.left using the <<--> key.
iii. If upon entering your data you detect an error:
a) Press the key to erase the character at the
cursor position or
b) Press the key to erase the character
at the left of the cursor position.
iv. Entering the data you might use the key. If you
press it once a message "Typeover" wT-~Te displayed at
the bottom of the screen and you will be able to enter
any character at the position of the cursor (if any
character is already written in this position it will
be automatically deleted). If you press the key
twice, a message "Insert" will be displayed at the
bottom of the screen and you will be able to insert a
character at the cursor position without deleting the
character which might have existed there.
v. If any of the number values are not acceptable by the
program a message "Value out of range,accept?" will be
displayed at the bottom of the screen. You have to
press N in order to reenter the value.
vi. After entering the data into a field you can move to
the next field pressing the key or the < 4/ >
key. If you want to go back to the previous field
press the < + > key.
References
1. NRAES-3, 1978.
Greenhouses. NRAES -
Engineering Service,
Energy Conservation and Solar Heating
3. Northeast Regional Agricultural
Ithaca, N.Y.
2. Incropera, F. P. and D.P. DeWitt, 1981. Fundamentals of
Heat Transfer, John Wiley & Sons., Inc. New York.
R
H
J W
W HOUSE WIDTH
L : HOUSE LENGTH
H : HOUSE HEIGHT
R = RAFTER
LENGTH
G GABLE HEIGHT
(b)
FIGURE I1 (a) CURVED GREENHOUSE USING ONE MATERIAL
FOR THE WALL.
(b) GABLE GREENHOUSE USING ONE MATERIAL FOR
THE WALL.
r
L
--
H
(b)
W : HOUSE WIDTH
L : HOUSE LENGTH
H : HOUSE HEIGHT
R RAFTER
LENGTH
G GABLE HEIGHT
A : UPPER WALL
HEIGHT
B : LOWER WALL
HEIGHT
FIGURE 2: (a) CURVED GREENHOUSE USING DIFFERENT MATERIALS
FOR THE LOWER AND UPPER WALLS.
(b) GABLE GREENHOUSE USING DIFFERENT MATERIALS
FOR THE LOWER AND UPPER WALLS.
W- HOUSE WIDTH
L HOUSE LENGTH
R : RAFTER
LENGTH
G : GABLE HEIGHT
FIGURE 3' QUONSET GREENHOUSE.
Table 1: U Values for various Construction Materials
U Values,BTU/hrF ft2
Roof and wall coverings
Glass,single layer
Glass,double layer,1/4" space
Glass,triple layer,1/4" space
Polyethylene film,single layer
Polyethylene film,double layer
(separated)
Fiberglass reinforced panel
Wall Materials
Concrete block,8"
Cement asbestos board,1/4"
Concrete ,poured ,6"
Soft wood,1" nominal
Greenhouses with thin thermal
blankets
Perimeter
Uninsulated
Insulated
1.1
0.7
0.5
1.1
0.1
1.0
0.5
1.1
0.8
0.6
0.4_ 0.5
BTU/hr F ft
0.8
0.4
Notice: The roof and wall materials that are most used
(in Florida) are Polyethylene (double layer) and
Fiberglass.
Material
Table 2: Air Exchange for Greenhouses
Construction System
Air Exchanges per hour
New construction, glass or fiber_
glass
New construction, double layer PE
Old construction,glass,good main_
tenance
Old constructionglass,poor main_
tenance
0.75 to 1.50
0.50 to 1.00
1.00 to 2.00
2.00 to 4.00
version i.UV
(ci ii7, iFAS
The institute of Food and Agricultural Sciences
of Florida and the authors of this software mak4
implicit warranties on the use of this software
ability for ail consequences of using this softwai
with the user.
, The University
e no explicit or
re.The responsi-
e remain solelyi
CRT I
INSTITUTE UF FUU HNU AGRICULTURAL SCItNi
Agricultural Engineering Department
University of Florida
Estimation of Greenhouse Heat Losses
Estimation of
Greenhouse Heat Losses
MAIN MENU
1. Gable Greenhouse Using One Material For The Wall.
2. Gable Greenhouse Using Different Materials For The Upper and Lower Wall.
3. Curved Greenhouse Using One Material For The Wall.
4. Curved Greenhouse Using Different Materials For The Upper and Lower Wall.
5. Quonset Greenhouse.
6. Exit to OPERATING SYSTEM.
Enter Selection:
CRT 2
I
Gable Greenhouse Using One Material Fi
Green
Sail H
House
House
Raftei
Gable
U Fac
U Fac
U Fac
U Fac
Nuebe
Tempbe
Teape
house Characteristics
eight:
Width:
Length:
r Length:
Height:
tor Of Single Material Wall:
tor Of Rafter -Material:
tor Of Roof Material:
tor Of Perimeter:
r Of Individual Houses:
r Of Air Exchanges Per Hour:
rature Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
i*l
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
0.00 B
0.00 B
0.00 B
or The Wall
ft
ft
ft
ft
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft
F
TU/hr
TU/hr
TU/hr
CRT 3
Gable Greenhouse Using One Material For
house Characteristics
Green
Hall
House
House
Rafte
Gable
U Fac
U Fac
U Fac
U Fac
Nusbe
Nuabe
Tempe
Height:
Width:
Length:
r Length:
Height:
tor Of Single Material Wall:
tor Of Rafter Material:
tor Of Roof Material:
tor Of Perimeter:
r Of Individual Houses:
r Of Air Exchanges Per Hour:
rature Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
Exit edit mode?
8.00
40.00
96.00
22.40
10.00
1.10
1.10
1.10
0.80
I
1.50
ft
ft
ft
ft
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft
F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 4
The Wall
e Greenhouse Using One Material Fi
Gabl
Greenhouse Ch1
Mall Height:
House Width:
House Length:
Rafter Length:
Gable Height:
U Factor Of Si
U Factor Of Ra
U Factor Of Ro
U Factor Of Pe
Number Of Indi
Number Of Air
Temperature Di
iracteristics
8.00
40.00
96.00
22.40
10.00
1.10
1.10
1.10
0.80
1
1.50
60.00
ingle Material Hall:
after Material:
>of Material:
riseter:
ividual Houses:
Exchanges Per Hour:
difference:
or The Hall
ft
ft
ft
ft
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft
F
Final Results
Conduct
Infiltra
Total He
Return to a
on Heat Losses:
tion Heat Losses:
at Losses:
ain menu?
CRT 5
466924.80
89856.00
556780.80
BTU/hr
BTU/hr
BTU/hr
Gable Greenhouse I
Greenhouse Charac
Using Different Materials For The Upper a
teristics
Wall Height:
Lower Wall Height:
Upper Wall Height:
House Width:
House Length:
Rafter Length:
Gable Height:
U Factor Of Lower Wall Material:
U Factor Of Upper Wail Material:
U Factor Of Rafter Material:
U Factor Of Roof Material:
U Factor Of Perimeter:
Number Of Individual Houses:
Number Of Air Exchanges Per Hour:
Temperature Difference:
Final Result
Conduction Hi
Infiltration
Total Heat L
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0
0.00
00
0.00
0.00
0.00
s
eat Losses:
Heat Losses:
losses:
ft
ft
ft
ft
ft
ft
ft
BTU/hr F f
BTU/hr F f
BTU/hr F f
BTU!hr F f
BTU/hr F f
F
BTU/hr
BTU!/hr
DTUihr
CRT 6
I
nd Lower Wall
t2
t2
t2
t
-..-j
Gable Greenhousi
Greenhouse Char:
Wall Height:
Lower Wall Heigt
Upper Wall Heigh
H unn Widrh:
House Length:
Rafter Length:
Gable Height:
U Factor Of Lo
U Factor Of Up
U Factor Of Ra
U Factor Of Ro
U Factor Of Pe
Number Of Indi
Number Of Air
Temperature Di
Final Results
SConduction Hea
Infiltration H
Total Heat Los
Exit Edit Mode?
WE
pe
ft
of
ri
vi
Ex
ff
e Using Different Materials For The Upp
acteristics
it:
it:
r Wall Material:
r Wall Material:
er Material:
Material:
meter:
dual Houses:
changes Per Hour:
erence:
8.00
2.00
6.00
40.00
96.00
22.40
10.00
1.10
1.10
1.10
1.10
0.30
1
1.50
60.0
t Losses:
eat Losses:
ses:
ft
ft
ft
ft
ft
ft
ft
BTU/hr
BTU/hr
BTU/hr
BTU/hr.
BTU/hr
er and Lower Wall
F ft2
F ft2
F ft2
F ft2
F ft
F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 7
Gable Sreenhou
Greenhouse Cha
Wall Height:
House Width:
House Length:
Rafter Length:
Gable Height:
Lower Wall Hei
Upper Wall Hei
U Factor Of Ra
U Factor Of Ro
U Factor Of Pe
Number Of Indi
Number Of Air
Temperature Di
Final Results
Conduction He
Infiltration
Total Heat Lo
Return to Main M
se Using Different Materials For The Upper
racteristics
ght:
ght:
after Material:
of Material:
rimeter:
vidual Houses:
Exchanges Per Hour:
fference:
at Losses:
Heat Losses:
sses:
enu?
8.00
40.00
96.00
22.40
10.00
2.00
6.00
1.10
1.10
0.80
1
1.50
60.00
466924.80
89856.00
556780.80
ft
ft
ft
ft
ft
ft
ft
BTU/h
BTU/h
BTU/h
F
BTU/h
BTU/h
BTU/h
;r F
r F
r F
and Lower Wall
ft2
ft2
ft
r
r
r
CRT 8
urved Greenhouse Using One Material For The W
Creenhouse I
Uall Height
House Width
House Lengt
Rafter Leng
Gable Heigh
U Factor Of
U Factor Of
U Factor Of
U Factor Of
Number Of Ii
Number Of A
Temperature
Characteristics
h:
th:
t:
Single Material Hall:
Rafter Material:
Roof Material:
Perimeter:
individual Houses:
ir Exchanges Per Hour:
Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 9
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
ft
ft
ft
ft
ft
BTU/hr
BTU/hr
BTU/hr
BTU/hr
F
F ft2
F ft2
F ft2
F ft
all
Curved Greenhouse Using One Material For The W
use Characteristics
Ireenho
Wall He
House U
House Li
Rafter
Sable Hi
U Facto
U Factor
U Facto
U Facto:
Number
Number
Tempera
ight:
idth:
length:
Length:
eight:
r Of Single Material Wall:
r Of Rafter Material:
r Of Roof Material:
r Of Perimeter:
Of Individual Houses:
Of Air Exchanges Per Hour:
ture Difference:
lf inal Kesult
Conduction He
Infiltration
Total Heat Lo
Exit edit mode?
eat Losses:
Heat Losses:
sses:
8.00
40.00
96.00
44.90
3.00
1.10
1.10
1.10
0.80
1
1.50
ft
ft
ft
ft
ft
BTU/hr F
BTU/hr F
BTU/hr F
BTU/hr F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 10
25
all
ft2
ft2
ft2
ft
fee 1 1
.... L
s
Curved Greenhouse Using One Material
Greenhour
Hall Heig
House Ui
House Len
Rafter Li
Gable Hei
U Factor
U Factor
U Factor
U Factor
Number 01
Number Of
Temperat:
se Characteristics
ht:
dth:
ngth:
length:
ght:
Of Single Material Wall:
Of Rafter Material:
Of Roof Material:
Of Perimeter:
f Individual Houses:
Air Exchanges Per Hour:
ure Difference:
Final Results
Conductio
Infiltrat
Total Hea
Return to ma
n Heat Losses:
ion Heat Losses:
t Losses:
in menu?
CRT 11
8.00
40.00
96.00
44.90
3.00
1.10
1.10
1.10
0.80
1
1.50
60.00
For The Wall
ft
ft
ft
ft
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft
F
BTU/hr
BTU/hr.
BTU/hr
451454.40
69120.00
520574.40
Curved Greenhouse
Greenhouse Charac
Wall Height:
LoNer Mall Height
Upper Wall Height
House Width:
House Length:
Rafter Length:
Using Different Materials For The Upper
teristics
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0
0.00
0.00
Gable Height:
U Factor Of Lower Wall Material:
U Factor Of Upper Wall Material:
U Factor Of Rafter Material:
U Factor Of Roof Material:
U Factor Of Perimeter:
Number Of Individual Houses:
Number Of Air Exchanges Per Hour:
Temperature Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
ft
ft
ft
ft
ft
ft
ft
BTU/hr F fi
BTU/hr F f
fTIll? C IL
; hiugii r
BTU/hr F
BTU/hr F
F
and Lower Wall
t2
t2
ft2
ft
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 12
Curved Greent
Greenhouse CI
house Using Different Haterials For The Upp
characteristics
F
Final Results
Conduction Heat L
Infiltration Heat
Total Heat Losses
Exit edit mode?
osses:
Losses:
i:
8.00
2.00
6.00
40.00
96.00
44.90
3.00
1.10
1.10
1.10
1.10
0.80
1
1.50
er and Lower Wall
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft2
BTI JL_ "f
lnu/nr
Wall Height:
Lower Wall Height:
Upper Wall Height:
House Width:
House Length:
Rafter Length:
Gable Height:
U Factor Of Lower Wall Material:
U Factor Of Upper Wall Material:
U Factor Of Rafter Material:
U Factor Of Roof Material:
U Factor Of Periseter:
Number Of Individual Houses:
Number Of Air Exchanges Per Hour:
Temperature Difference:
F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 13
I
-m
r TZ
Curved Greenhou
Greenhouse Chai
Mall Height:
Lower Wall Heig
Upper Wall Heig
House Width:
House Length:
Rafter Length:
Gable Height:
U Factor Of Low
U Factor Of Upp
U Factor Of Raf
U Factor Of Roo
U Factor Of Per
Number Of Indiv
Number Of Air E
TantrartrT Oilf
Final Results
Conduction Hea
Infiltration H
Total Heat Los
Return to main me
ise Using Different Materials For Th
racteristics
)ht:
|ht:
ier Wall Material:
er Wall Material:
'ter Material:
f Material:
imeter:
idual Houses:
changes Per Hour:
ference:
t Losses:
eat Losses:
ses:
nu?
8.00
2.00
6.00
40.00
96.00
44.90
3.00
1.10
1.10
1.10
1.10
0.80
1
1.50
60.00
451454.40
69120.00
520574.40
ft
ft
ft
ft
ft
ft
ft
BT
BT1
BT
BT1
BT
F
BTU
BT1
BTU
e Upper and Lower Wall
U/hr F ft2
U/hr F ft2
U/hr F ft2
U/hr F ft2
U/hr F ft
U/hr
U/hr
/hr
CRT 14
I
Quonset Greenhouse
G reet
House
House
Rafte
Gable
U Fac
U Fac
U Fac
Nuebe
Tempe
house Characteristics
Width:
Length:
r Length:
* Height:
tor Of Rafter Material:
tor Of Roof Material:
tor Of Perimeter:
r Of Air Exchanges Per Hour:
rature Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
ft
0.00 ft
0.00 ft
0.00 ft
0.00 BTU/hr F ft2
0.00 BTU/hr F ft2
0.00 BTU/hr F ft
0.00
0.00 F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
CRT 15
30
guonset Greenhouse
Greenhouse
House Widt
House Len
Rafter Len
Gable Hei
U Factor (
U Factor
U Factor (
Number Of
Tesperatur
e Characteristics
th:
gth:
gth:
ght:
Jf Rafter Material:
Of Roof Material:
If Perimeter:
Air Exchanges Per Hour:
e Difference:
Final Results
Conduction Heat Losses:
Infiltration, Heat Losses:
Total Heat Losses:
Exit edit mode?
CRT I V-
40.00
96.00
49.70
10.00
1.10
1.10
0.80
1.50
ft
ft
ft
ft
BTU/hr F ft2
BTU/hr F ft2
BTU/hr F ft
F
0.00 BTU/hr
0.00 BTU/hr
0.00 BTU/hr
-m-mmm.-m -
uonset Greenhouse
Greenhouse Charac
House Width:
House Length:
Rafter Length:
Sable Height:
teristics
u actor UT Rafter naterial:
U Factor Of Roof Material:
U Factor Of Perimeter:
Number Of Air Exchanges Per Hour:
Temperature Difference:
Final Results
Conduction Heat Losses:
Infiltration Heat Losses:
Total Heat Losses:
362275.20 BTU/hr
46080.00 BTU/hr
408355.20 BTU/hr
return to main menu?
40.00
96.00
49.70
10.00
1.10
1.10
0.80
1.50
60.00
ft
ft
ft
ft
BTU/hr F
BTU/hr F
BTU/hr F
F
ft2
ft2
ft
Ri
. CRT 17
. 32
COOPERATIVE EXTENSION SERVICE, UNIVERSITY OF FLORIDA, INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES, K.R. Tefertiller,
director, in cooperation with the United States Department of Agriculture, publishes this information to further the purpose of the May 8 and
June 30, 1914 Acts of Congress; and is authorized to provide research, educational information and other services only to individuals and institu-
tions that function without regard to race, color, sex or national origin. Single copies of Extension publications (excluding 4-H and Youth publica-
tions) are available free to Florida residents from County Extension Offices. Information on bulk rates or copies for out-of-state purchasers is
available from C.M. Hinton, Publications Distribution Center, IFAS Building 664, University of Florida, Gainesville, Florida 32611. Before publicizing this publication,
editors should contact this address to determine availability.
|
