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RAPPORT NO. 2357
E. Haas, Ir. G.H. van Nieuwenhuizen, H.A.M. Boerrigter, R.G. Bons
FACTORS INFLUENCING THE CONDUCTIVE DUCTIVE HEAT TRANSFER THROUGH HYACINTH BULBS PACKED IN CLOSED OR VENTED CARTONS
Uitgebracht aan de directeur van het Sprenger Instituut Project no.
ISSN 0169 765X 11 november 1988
SUMMARY
Experiments were carried out with hyacinth bulbs, with the aim to determine the influence of the bulbs' heat produced by respiration and of the carton vent holes, on the bulbs cooling rate, and on the effective thermal conductivity. For the first and third experiment a closed carton was used. For the second experiment 6% vent holes were provided on the carton bottom and for the fourth experiment the carton cover had the same percent of vent holes.
In all these experiments the cartons containing flower bulbs were stacked on a cold plate with a constant temperature (3-4 C) and one dimensional heat flow perpendicular to the cold plate, was ensured.
Two finite differrence models were used to calculate the bulb temperature (from all the seven layers) and the surrouonding air temperature.
The results show that the cooling process based on heat conduction (in one direction only) is influenced by the bulbs' respiration rate. When the heat produced by respiration was high (during the first experiment) the bulbs' temperature from the last layers was increased instead of decreased. The vents provided in the carton bottom or in the cover have some positive influence on the bulbs' cooling rate, in particular the layers near the vents. A good agreement was found between the calculated and measured temperature of the bulbs in all layers.
For the air surrounding the bulbs a good agreement was found between the measured and calculated temperature for some layers only.
van de warmteproduktie en de toepassing van ventilatiegaten in de dozen op de afkoeling en de effectieve warmtegeleiding.
Tijdens experiment 1 en 3 werd een gesloten doos gebruikt. Voor experiment twee is een doos met 6% ventilatie-opening in de bodem toegepast en in het vierde experiment is het deksel voorzien van 6% ventilatie-opening.
Tijdens alle vier experimenten waren de dozen met bloembollen op een koude plaat gestapeld met een constante temperatuur (3-4 C ) . Hierbij is gezorgd voor een ééndimensionale warmtestroom loodrecht op de koude plaat.
Twee eindige differentiemodellen zijn gebruikt om de boltemperaturen (in alle zeven lagen) te berekenen evenals de omgevende luchttemperaturen.
De resultaten laten zien dat het koelproces gebaseerd op warmtegeleiding (in een richting) wordt beïnvloed door de warmteproduktie van de bloembollen. Bij een hoge warmteproduktie (experiment 1) namen de boltemperaturen toe in plaats van af.
De ventilatiegaten in de bodem of in het deksel hebben beide een positieve invloed op de afkoelsnelheid vooral in de lagen bij de openingen.
Een goede overeenstemming werd gevonden tussen de berekende en gemeten temperaturen in alle lagen. Ook voor de luchttemperaturen rond de bollen werd een goede overeenkomst gevonden tussen de metingen en de berekeningen maar slechts in enkele lagen.
INTRODUCTION
All the hyacinths bulbs used for forcing in the U.S. and Canada are produced in The Netherlands (3).
For Ocean transport two types of packing materials are widely used: wooden or plastic trays and cardboard boxes.
Since the spring flowering bulbs require ventilation which is essential for proper development of the bulbs during transport the cartons are provided with vent holes.
Several research works have shown that by providing the carton wall perpendicular to the air flow direction with vent holes it is possible to reduce the pressure drop across the package and to improve the air and
temperature distribution in the cargo (4-7). But generally the cartons are stacked in a shipping container in such a way that the cooling or heating process is determined by heat conduction only in the center of the stack (2). In this case it is interesting to know the factors which influence the cooling rate.
The aims of the research were :
1. To determine the cooling rate of hyacinths bulbs packed in a closed or vented carton.
2. To evaluate the influence of the bulbs respiration rate and of the vent holes provided on the top or the bottom of the carton on the cooling rate and on the effective thermal conductivity.
3. To compare the measured cooling rate of the bulbs and the air from different layers with the calculated one based on a finite difference model.
TEST PROCEDURE AND PRESENTATION OF RESULTS
In this research only the case of one-dimensional conduction heat flow was considered. Therefore the experimental carton with the dimension of 48 x 30 x 25 cm was placed in the middle of a cold plate.
Through this plate a constant temperature liquid (water with glicol) was pumped by a Colora Cryostat.
To ensure one-dimensional heat flow in the direction perpendicular to the cold plate, the bottom of the cold plate was insulated and around the experimental carton containing hyacinth bulbs six other cartons containing the same bulbs were placed (Fig. 1 ) . The exterior walls of these cartons were insulated with a
10 cm polystyrene layer. A polystyrene 10 cm layer covered also all the cartons.
In each carton, the bulbs were arranged in 7 layers each containing 120 bulbs arranged as uniformly as possible. The temperature of two bulbs (measured in the bulb center) and of the air surrounding them (two points) were measured with fine copper constantan thermocouples (0,5 mm diameter of the wire), in each layer.
The plate surface temperature was measured at five different points and the average value was used. A "Fluke" datalogger recorded all the thermocouples every hour.
The cold plate non-insulated surface was provided with a heat flow meter which was also connected to the same data logger.
Two finite difference model were used to calculate the cool down of the bulbs and to calculate the surrounding air temperature. The model used to calculate the bulbs temperature takes into account the convective heat transfer between the bulbs and the cold air from the void spaces, the conduction heat between
energy balance for each node is given by ec. 1. k_ A. 1 (Tn. . - Tn. .) k_ A. (Tn. - Tn. .) f l+l v l+l i-I' f l v l i-l/ , . ,mn Tn . , „n AX. , AX. 1+1 1 ._ n+1 n m.c_ (1. - I .) l f l l At - hA (T . - I .) + Q •= s i l r (1) , 1
The value of T. can be calculated from formula 2.
l
k,. A. - At k. A. .. At k_ A. At h A At
n+1 = _ 1 _ ^ L + 1 n . _ f _ i + l f _ 2 _ s n
1 A 1+1 A A 1
m. c_ Ax. , m. c. Ax. , m. c^. Ax. m. cr
l f l+l l f l+l l f l i f k- A. At h A At Q n At + - ^ Tn. . + — 5 — In. + ^ (2) l-l l v m. c- Ax. m. cr m. cr l f l i f i f where
kf = fruit thermal conductivity [W/mK]
2
A - exposed surface area of the fruit [cm ]
2
A. = average cross section area for conduction between fruit i and i-1 [cm Ax. = distance between nodes i and i-1 [cm]
l l '
At — length of time step [h] T . = temp of node i and step n [K]
I . = temperature of the air surrounding node i at time step n [K]
2
h = convective heat transfer coefficient [W/m K] m. = mass of fruit [kg]
Cr. - fruit specific heat [Wk]
-6-By taking At = 1 hour
A.,1 = A.; Ax. . = Ax.
l+l l l+l l for the layers 2 to 6
Ax. Ax Ax. = for layer 1 and Ax. ^ - for layer 7
i 2 i+l 2 i+1 k,. A. f i and by noting = P m. cr Ax l f h As Q n = N and — R l f i f Equation 2 becomes T.n + 1 = Tn. ,p + Tn. (1-P-P-N) + P Tn. . + Nln. + R (3) l i+lr l l+l l
This equation was used only for the layers 2-6.
For the first and last layer was used also
K£ A.
PI £ - 1 nu C i (Ax/2)
For the first layer equation 2 becomes:
Tn+1 _ Tn + T n _ _ N ) + p T + m n + R
i+l l 1 1 l-l l 1
For the last layer equation 2 becomes:
T i n + 1 = Tn i + 1 Px + T™ (1 - Px - P - N) + P Tn i ; L + N I ^ + R (32)
For the calculation of heat and mass transfer in the void space each bulb is assumed to be surrounded by air whose volume is equal to the volume of the void space increased with some slow air movement (3 cm/sec were measured with a DISA hot wire annemometer in the carton with 6% vent holes in its bottom). Each node
is subjected to convection heat flow from the bulb toward the plate and evaporative cooling due to water losses.
The nodes are located at the same levels from the cold plate as the bulb nodes, fig. 2.
rn Tn . ,Tn Tn 1 ï+l ï+l ï x ï i ï-l n n — — — - - ^ - + h S (T . - I .) - L.WS = 1 ï * AX. n Ax. 1+1 1 1 l n-+l Tn At (1/ - ï \ ) (4) n-1
The value of I. can be calculated from formula:
l k, A. 1 At k, A. . At k, A. At
n+1 _ J_l+1
+_ _L^±1 L^:
1 . 1+1 ml cl A x i + 1 ml cl A x i + 1 ml cl A xl h S At k , A. At h S At LnWS At ) In. + i In. , + Tn. - - ^ (5) l „ l - l l ra1 Cj n^ Cj Ax. m^ Cj m^ c^ where : kx = a i r t h e r m a l c o n d u c t i v i t y [W/m.K] 2A. = average cross section area for the air surrounding the bulb [cm ]
I . = air temperature at node i and time step n [ K]
mx = mass of volume of air at node i [kg]
cx - air specific heat [W/kg]
W - weight losses for a bulb [kg]
L = X — distance between nodes [cm]
2
S = As - exposed surface area of the fruit [cm ]
To calculate the effective thermal conductivity of a layer of 25 cm hyacinth bulbs packed in a corrugated carton with or without vent holes the following
formula was used.
qs E
U
where
E - effective thermal conductivity [W/m.K]
q = heat flow through the carton with flower bulbs (measured by the heat flow meter) [W/m ]
s - thickness of the bulbs layer [m]
U = T - T
t P where :
T = temperature on the top of the carton T = temperature of the cold plate
The factors which can influence the cooling rate are the heat produced by respiration, the evaporative cooling of the water losses and the carton vent holes.
Before each experiment the bulbs' respiration rate was measured using the head space accumulation method.
In this method a stainless steel vessel with volume of 68 1 is used. Into this vessel 10 kg of hyacinth bulbs, with a known specific weight are introduced. The bulbs are arranged in a wire mesh container which is in contact with the vessel in four points only, in order to allow a good air penetration through
the bulbs, and to assure a uniform climate.
The vessel is closed hermetically only a P.V.C. tube connects it with an Infra Red Co2 analyzer type ADC-SSI with the range 0-10%.
The accumulation of C02 in time is measured in the range 0-1% only since higher
levels can have some influence on the respiration rate. The C02 production can
be calculated with the formula:
VI - VP A C02
PG02 x x 60
m At
where :
PC02 - C02 production, ml/kg.h
VI = volume of the vessel, ml Vp =• volume of product, ml m - mass of bulbs in kg AC02/At - % C02/min
The C02 production as a result of respiration is transformed in heat production
divided by a coefficient of 0.168 [lC02/h.W] which was given for apples in (1).
The weight losses of each layer of bulbs were determined by weighing the bulbs before and after each experiment.
The bulbs specific weight was measured by using the water déplacement method. The two principal dimensions of 100 bulbs, the maximal diameter and the length
(fig. 3) were measured at the beginning and the end of the experiments with a vernier Caliper.
The exterior surface of the bulb was calculated. The data are presented in table 1.
Table 2 shows the changes occurred during the experiments concerning the bulbs' characteristic data.
RESULTS AND DISCUSSION
Four experiments were carried out. During the first two experimnents the bulbs' respiration rate was higher (see table 2) and during the last experiments the bulbs' respiration rate became slower. It is possible to compare the cooling rate of the bulbs and of the surrounding air from different layers during the
first two experiments in fig. 4-6. For the first experiment the bulbs were packed in a closed carton and for the second experiment a carton provided with 6% vent holes in its bottom was used.
In fig. 7-9 the cooling rate of the bulbs and surrounding air are compared during the two last experiments.
For the third experiment the bulbs were packed in a closed carton and for the fourth one a carton provided with 6% vent holes area uniformly distributed on the carton cover was used.
Important to note that all the fig. 4-9 present not only the measured
temperature but also the calculated one using two finite difference computer programmes. One for bulbs temperature and the other for air temperature. These programmes are given in annexe 1 and 2.
The correlation between the effective thermal conductivity E calculated with eq 6 and the temperature difference U for the first two experiments was given in fig. 10 and for the last one in fig. 11.
Figs. 4 and 5 show that when the bulbs repirations rate was not so high (experiment two) and a carton with 6% vent holes in its bottom was used, the bulbs cooling rate, from all the layers was faster and more uniform. During the first 10-15 h the bulbs temperature from the last four layers was increased with 1.5-2.7 C during the first experiment (fig. 5 ) .
The temperatures increase was slower during the second experiment (only 1 C ) . It is not sure that this is the effect of the carton vent holes perhaps also
the respiration rate has some influence.
From fig. 5 is also possible to see that 50 hours after the carton was put on a cold plate (with a temperature of 3-4 C) the temperature of the bulbs from the last layer was still 25 C, as it was at the beginning of the first experiment. This fact shows that the conduction heat transfer cannot assure the cooling of products with high respiration rate during a short time 50 h. Important to note that for the same time period, during the second experiment the bulbs
temperature from the last layer decreased till 19 C.
The differences between the measured and calculated temperatures for different layers were smaller for the second experiment, 0.3-0.5 C. Perhaps this is the effect of more uniform respiration rate of the bulbs from different layers, as A result of a more uniform cooling temperature.Fig. 6 shows that by using the data from Annex 2for the computer model it is possible to calculate also the temperature of the air.
It is necessary to note that it is difficult also to measure the air
temperature since the thermocouple can touch a bulb so that for some layers the difference between the calculated and measured value is higher. Two factors have an important influence on the calculated air temperature. The quantity of air which is near the bulb and the evaporative cooling of the water lost by the bulbs. By trying different values for the mass of air present in the space around each bulb it was found that 0,04 kg/h is the best one. The mass of air was calculated from the average cross section area for the air surrounding the bulb multiplied by the air velocity and density. The value shows that the air
around the bulbs has some velocity. In fact at the end of the second experiment the air velocity on the top of the bulbs was measured with a DISA hot wirre annemometer and it was found that the air velocity into the carton was 3 cm/sec when the carton bottom is provided with 6% vent holes.
From fig. 7 it is possible to see that when the bulbs respiration rate is reduced the cooling rate of the first three layers is quite the same in a closed or in a carton with 6% vent holes area on its cover. But by regarding fig. 8 it seems that the vent holes provided on the top of the carton have some positive effect on the cooling rate of the last four layers and on the cooling
•10-rate uniformity, so that the temperature differences between the layers became smaller.
Fig. 9 shows that the vent holes from the carton cover have a positive influence on the air cooling rate. This influence is not only in the last layers but also in the second layer.
Fig. 10 compares the effective thermal conductivity of a 25 layer hyacinth bulbs packed in a closed carton or in a carton with 6% vent holes in its bottom and it is possible to remark that the high respiration rate during the first experiment has a negative influence on the uniformity of the quantity of heat flowing through the carton.
When the heat of respiration decreases to 0.104 W/kg (see Table 2) and a carton with 6% vent holes in its bottom is used the effective thermal conductivity
o remains quite constant for a temperature difference of 16-21 C.
The effective thermal conductivity decreased when the bulbs' respiration rate is reduced but its value remains quite the same when the bulbs are packed in a closed carton (fig. 11).
From the same figure can be seen that the vent holes provided on the carton cover have a negative influence on the uniformity of the effective thermal conductivity.
CONCLUSION
The cooling process based on conductive heat transfer is influenced by the bulbs' respiration rate. When the respiration rate was high the temperature of the last layers was increased instead of decreased.
At the end of the cooling time (50 hours) a large range of temperatures are found in a small carton (25 cm height).
The air into the carton especially in a carton with 6% vent holes in its bottom has a slow velocity of 3 cm/sec.
Two finite difference models were developed one for the bulbs and one for the air surrounding them, for calculating the conductivity heat transfer through a carton with seven layers of hyacinth bulbs with different respiration rate and weight losses.
A good agreement was found between the calculated and measured bulbs' temperature from all the layers.
For the air surrounding the bulbs, a good agreement was found between the measured and calculated temperature of some layers only.
It seems that the vent holes provided in the top or bottom of the carton have some positive influence on the cooling rate of the air from the layers near the vent holes, so that for conductivity heat transfer it is also recommended to use cartons with vent holes.
REFERENCES
1. Anonim, 1984. Produktgegevens groente en fruit. Appel 06. Mededeling Nr. 30 Sprenger Institute.
2. Chau, K.V., Gaffney, J.J., Baird, C D . , 1985. Transient heat and mass transfer for oranges in closed containers. Proceeding of the Orlando IIR Congress 1985 pp. 87-93.
3. De Herthog, A., 1985. Holland bulb Forcer's guide. Dep. of Horticultural Science. N.C. State University.
4. Haas Elise and Felsenstein, G., 1987. Factors affecting resistance to air flow through avocados packed in fiber board crates. Proceedings of the XVII International IIR Congress Vienna. p[p. 125-131.
5. Mitchell, F.G., Person, R.A. and Mayer, C , 1971. Cooling trials with
plastic tray pack nectarines in various containers. Calif. Agr. 25(9)13-15. 6. Ray, E. McDonald and Camp, Th., 1973. Effectivenes of three types of
ventilations openings in full telescope corrugated citrus carton ARS 25. 7. Wang, J.R., and Tunpun, R., 1968. Forced air precooling of tomatoes in
•12-TABLE 1
Flower bulbs characteristic data (Hyacinth cv. Pink Pearl, size 10-12)
Time of Before the first After the last Mean
measurement experiment experiment Decrease - - in %
Data Mean Minimun Maximum Mean Minimum Maximum Bulbs' diameter (cm) 3.46 3.02 3.90 3.39 2.97 3.75 2.02 Bulbs' length (cm) 3.92 3.45 4.32 3.85 3.14 4.25 1.78 Bulbs' lateral sur-face calcula-ted (cm ) 33.89 27.01 41.03 33.06 25.37 38.66 2.45
TABLE 2 Characteristic Measuring time Bulb mean weight (gr) Weight losses during the exp. (%) Specific weight kg/m Heat of respiration measured (W/kg) Weight of bulbs in the carton (kg) Box Duration of exp
date for all the First exp. 28.7.1988 22.3 4.57 1.098 0.163 18.732 closed 50 h four experiments Second exp. 8.8.1988 20.6 2.42 1.062 0.104 17.304 bottom open 50 h Third exp. 22.8.1988 20.1 1.40 1.036 0.061 16.884 closed 50 h Fourth exp. 10.10.1988 19.1 1.08 1.016 0.054 17.381* top open 50 h * 130 bulbs in each layer
Wageningen, November, 8, 1988 EH/AvH
1. Cold plate
2. Lateral insulation 3. Polystyrene cover 4. Experimental carton 5. Heat flow meter
Figure 1: Experimental lay out
a. top view without the polystyrene cover b. vertical section
T = for bulbs température I = for air temDerature Tp = temp, of the cold plate
T0 = temp of the carton bottom
temp, of the carton top
w;m^w>m>Àw>7/s//y/s,
Figure 3:
The exterior surface of a hyacinth bulb S, and the specific dimension D = maximal diameter L = bulbs length Si = 2 x n x £ '1 D
S
2= n x -J x / ( | )
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I ++I + I + : I + I I I M I A I L I I C I 0 0.40 I N I + + ++++ D I + + +:+ + + + I I U I C I I I I 0.35 I ! w -+ + + + + +-/ 17. 18. 19. 20. 21. 22. m K TEMP DIFFERENCE,C Figure 10:Correlation between the effective thermal conductivity E and the temperature difference U, for the first two exoeriments
R 0.40 M A L C 0 0.35 N D U C
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/ m 0.30 I I I I I I I I I I I I I 6. 1 7 . -H-+ + -H- + -t-+ +++ + : + + + + 1 8 . 1 9 . + ++ -H- + 2 0 . + I I I I + + I ++ I I I I I I I I 2 1 . TEMP DIFFERENCE,CCORRELATION BETWEEN E and U, EXPER.4 FLOWER BULBS
+ + + + + -I + I + I + I + I + I + + I ++ I I I I I I + + + I -H-+ I I I I I I ++: ++ I +++: +:+ i : : + + + +-17. 18. 19. 20. 21. TEMP DIFFERENCES Figure 11 :
Correlation between the effective thermal conductivity E and the temperature difference U for the last two experiments
T H E R M A L C 0 N D U C W / m - + 0 . 4 0 I I I I I I 0 . 3 5 I I I I I I 0 . 3 0 I -+ 1 6 .
PROGRAMME FOR CALCULATING THE BULBS COOLING RATE (SECOND EXPERIMENT) open' Fl.dat';channel=2;width=350 units [nvalues=50] READ [CHANNEL=2]J,T0,I1,T1,I2,T2,I3,T3,I4,T4,I5,T5,I6,T6,I7,\ T7,Tp,Tt,Ta,Q SCALAR [VALUE=0.47] KF SCALAR [VALUE=0.022] MI SCALAR [VALUE=1.98] AI SCALAR [VALUE=1.050] CF SCALAR [VALUE=0.57] H SCALAR [VALUE=34] AS SCALAR [VALUE=3.8] X SCALAR [VALUE=0.00185] QR CALCULATE Ll-X/2 CALCULATE P-(KF*AI)/(MI*CF*X*1000) CALCULATE P1=(KF*AI)/(MI*CF*L1*1000) CALCULATE N=(H*AS)/(MI*CF*1000) CALCULATE R==QR/(MI*CF) CALCULATE 01=(P*T2)+T1*(1-P-P1-N)+(P1*TO)+(N*I1)+R CALCULATE 02=(P*T3)+T2*(1-P-P-N)+(P*T1)+(N*I2)+R CALCULATE 03«(P*T4)+T3*(1-P-P-N)+(P*T2)+(N*I3)+R CALCULATE 04=(P*T5)+T4*(1-P-P-N)+(P*T3)+(N*I4)+R CALCULATE 05=(P*T6)+T5*(1-P-P-N)+(P*T4)+(N*I5)+R CALCULATE 06=(P*T7)+T6*(1-P-P-N)+(P*T5)+(N*I6)+R CALCULATE 07=(Pl*Tt)+T7*(l-Pl-P-N)+(P*T6)+(N*I7)+R CALCULATE Z=J+1
TEXT T;VALUES-' BULBS COOLING RATE,CALCULATED and MEASURED,\ EXP.2'
GRAPH [TITLE=T;YTITLE='TEMPERATURE ,C';\
XTITLE='COOLING TIME,HOURS';YLOWER=9;YUPPER=25 ;XLOWER=0;\ XUPPER-50;NROWS=49;NCOLUMNS=51];\
Y=T1,T2,T3,01,02,03 ;X-J,J,J,Z,Z,Z;\
METH0D=P0INT,POINT,POINT,POINT,POINT,POINT ;\ SYMBOL-'o','x','i','#','+','$'
open' F.dat';channel=2;width=350 units [nvalues=50] READ [CHANNEL=2]J,T0,I1,T1,I2,T2,I3,T3,I4,T4,I5,T5,I6,T6,I7,\ T7,Tp,Tt,Ta,Q SCALAR [VALUE=0.031] K 1 SCALAR [VALUE=0.04] MI SCALAR [VALUE=2.8] A SCALAR [VALUE=0.293] CI SCALAR [VALUE=0.57] H SCALAR [VALUE=34] S SCALAR [VALUE=3.8] L SCALAR [VALUE=694] LI SCALAR [VALUE=0.000102] W CALCULATE L2=L/2 CALCULATE P=(K1*A)/(MI*C1*L*1000) CALCULATE Pl=(K1*A)/(MI*CF*L2*1000) CALCULATE N=(H*AS)/(MI*C1*1000) CALCULATE V=(L1*W*S)/(MI*C1*1000) CALCULATE 01=(P*I2)+I1*(1-P-P1-N)+(P1*TO)+(N*T1)+V CALCULATE 02=(P*I3)+I2*(1-P-P-N)+(P*I1)+(N*T2)+V CALCULATE 03=(P*I4)+I3*(1-P-P-N)+(P*I2)+(N*T3)+V CALCULATE 04-(P*I5)+I4*(l-P-P-N)+(P*I3)+(N*T4)+V CALCULATE 05-(P*I6)+I5*(l-P-P-N)+(P*I4)+(N*T5)+V CALCULATE 06=(P*I7)+I6*(1-P-P-N)+(P*I5)+(N*T6)+V CALCULATE 07=(Pl*Tt)+I7*(l-Pl-P-N)+(PI*I6)+(N*T7)+V CALCULATE Z=J+1
TEXT T;VALUES=' CALCULATED and MEASURED AIR TEMP. EXP.1' GRAPH [TITLE=T;YTITLE='TEMPERATURE ,C';\
XTITLE='COOLING TIME,HOURS';YLOWER-19;YUPPER=27 ;XLOWER=0;\ XUPPER-50;NR0WS=49;NCOLUMNS=51];\
Y=I3,I4>I6,I7,03,04,06)07;X-J,J,J,J,Z,Z,Z,Z;\
METHOD-POINT,POINT,POINT,POINT,POINT,POINT ,POINT,POINT ;\ SYMBOL-'o','x','i','c','#','$','+','*'
