control Solar Kiln with help of arduino uno

Drying of agricultural products is one of the applications where solar energy can be efficiently utilized. The reason for this is that the drying process requires low grade energy since high air temperature may damage the dried material. Several investigators have proposed many geometries and arrangement that use solar energy in drying. These geometries can be classified into two types.

Ø Solar collectors are used separately to preheat the ambient air before it is supplied to the dying.

Ø The solar collector and the drying are integrated is one structure.

In this system, ambient air is first heated in the solar collector and is then circulated by natural draft through the drying bin. [1]

Lumber is usually dried to specific moisture content prior to further manufacturing or use. The amount of water in wood is usually expressed as moisture content and can be directly measured or calculated. The moisture content of wood is defined as the ratio of the weight of water in wood to the dry weight of the wood material. While lumber can be air-dried, the humidity in most localities prevents the lumber from reaching the moisture content required for the stability needed for interior use. A dry kiln is required to dry lumber to the necessary final moisture content and does so fairly rapidly. This publication discusses the design and operation of a solar-heated lumber dry kiln that is designed to be inexpensive to construct and simple to operate. [1]

Figure 1 Solar Kiln (Made in paint for concept). [1]

Where;

Sun Radiation= sun light direct incident with Acrylic Sheet

Ambient Air = inlet Air to interior system of Solar Kiln

1.2 Components of solar kiln

Solar Kiln Main component consists of

1. Acrylic Sheet

2. Fans (two-sets) and Relay Control

3. Humidity and Temperature Sensor

4. Arduino UNO

5. Lcd Display (16×2) and Buttons for setting

6. Dc-Motor and shaft, Battery (12V)

7. Insulation Sheet.

Figure 2 Components of Solar Kiln [1]

1.2.1 Acrylic sheet

The acrylic sheet is ceramic material with high temperature capability. Acrylic Sheet change the Sun Light wave length, when sun light passed through it.

1.2.2 Fan and relay control

Fan used as exhaust of Air. We used dc-fan in the Solar Kiln project because only for testing the system. Relay Control used as ON/OFF switch.

1.2.3 Arduino uno

There are a number of different Arduino boards; we will be using one of the most popular, the Arduin Uno.The Uno has a number of input ports which can be used to read in signals from other Sensor and Fan, and output ports which can be used to drive external lights, speakers, motors and LCD.

Program:

// SOLAR KANAL PROJECT

// GROUP MEMBERS

#include <dht.h> // library file for dht11 sensor

#include<LiquidCrystal.h> //library file for lcd

LiquidCrystal lcd(13,12,8,9,10,11); // pins define for lcd

int relay=6; // pin for fan on and off

int val; // variable define

int pin=4; // for ldr sensor

int led=2; // led is used in pin 2

float var=0; // variable used to store value

float var1=0; // variable used to store value

int pin2=A0; // FOR temperature sensor LM35

dht DHT; // library file

#define DHT5_PIN 5 // pin define for Humidity sensor

void setup()

{

Serial.begin(9600); // serial communication

Serial.println("SOLAR KANAL PROJECT");

Serial.print("Humidity and temperature control ");

Serial.println();

Serial.println("\tHumidity (%),\tTemperature (C)");

lcd.begin(16,4); // lcd define

pinMode(relay,OUTPUT); // fan output

pinMode(pin,INPUT); // FOR IR SENSOR READ

pinMode(led,OUTPUT); // led pin value as output

pinMode(DHT5_PIN,INPUT); // FOR HUMIDITY SENSOR DHT11

pinMode(pin2,INPUT); // FOR TEMPERATURE SENSOR LM35

}

void loop()

{

float reading= analogRead(pin2);

float temp=(reading*0.48828125);

Serial.print("DHT11, \t");

float chk = DHT.read11(DHT5_PIN); //READ VALUE FROM DHT11 SENSOR PIN 5

{{

Serial.print("\t");

Serial.print(DHT.humidity, 1);

Serial.print(",\t");

Serial.println(temp);

// Serial.print("\t");

lcd.setCursor(0,0);

lcd.print("temp(C) = ");

// lcd.setCursor(0,1);

lcd.print (temp);

lcd.setCursor(0,1);

lcd.print("Humidity %=");

lcd.print (DHT.humidity);

}

delay(1000);

lcd.clear();

// conditions for on and off fan

// case 1 : when humidity >=60 and temperature is >=25 then fan is on

if(DHT.humidity>=60 && temp>=35)

{

digitalWrite(relay,HIGH); // its a negative trigger relay (relay light on at low trigger)

lcd.setCursor(0,0);

lcd.print("FAN IS ON");

}

if(DHT.humidity>=60 && temp<=35)

{

digitalWrite(relay,HIGH); // its a negative trigger relay (relay light on at low trigger)

lcd.setCursor(0,0);

lcd.print("FAN IS ON");

}

if(DHT.humidity<60 && temp>=35)

{

digitalWrite(relay,HIGH); // its a negative trigger relay (relay light on at low trigger)

lcd.setCursor(0,0);

lcd.print("FAN IS ON");

}

// case 2 : when humidity >=60 and temperature is <25 then fan is on

if(DHT.humidity <60 || temp<35)

{

digitalWrite(relay,LOW); // fan high means voltage at pin is high

lcd.setCursor(0,0);

lcd.print("FAN IS OFF");

}

delay(1000);

lcd.clear();

}

// coding for light detection

var= digitalRead(pin); // read data from digital pin

if (var>0) // if condition

{

digitalWrite(led,LOW);

lcd.setCursor(0,0);

lcd.print("LIGHT IS OFF ");

}

if (var==0)

{

digitalWrite(led,HIGH);

lcd.setCursor(0,0);

lcd.print("LIGHT AVAILABLE");

}

delay(1000);

lcd.clear(); [2]

1.2.4 Humidity and temperature sensor

Humidity is the presence of water in air. The amount of water vapor in air can affect human comfort as well as many manufacturing processes in industries. One of the tasks of air-Exhausting, depending on the existing internal and external effects, is to provide optimal temperature in the Solar Kiln. Temperature sensors are integral components of Solar Kiln and units. [3]

1.2.5 Dc motor and shaft

Dc motor covert electrical power to mechanical in the form of rotation in this system the dc motor is rotate shaft and with help of shaft we can able to adjust the angle of Acrylic Sheet. [4]

1.2.6 Battery

Dc Battery (12Volt) rechargeable li-Ion 6000mAh pack for Lcd, humidity & temperature sensor, to drive Dc-Motor for negligible time to adjust the angle for Acrylic sheet. [5]

1.2.7 Insulation

Insulation is to protect every system from damage. This way here we use it for to not direct effect the weather condition on the system of Solar Kiln. [2]

1.3 Exhausting fan and ambient air inlet

Fig 1.1 shows to regulate the air and temperature of the internal system and control it with achieved target value.

1.3.1 Exhausting fan

Exhaust fan is to control the temperature in the internal system. When temperature is high in the internal system from given target values, then the exhaust fan automatically control the internal temperature. [6]

1.3.2 Ambient air inlet

The ambient air inlet from the bottom of solar kiln is necessary to protect system from squeezing condition, not affect the structure of the system also to protect material (wood, corps) from damage. [7]

1.4 Advantages and disadvantages of solar kiln

1.4.1 Advantages

· . 1) Drying time is significantly shorter than air drying.

· 2) Drying quality is substantially better than air drying.

· 3) Drying to a very low equilibrium moisture content (e.g. 8-10%) is possible for most locations, compared with air drying.

· 4) The system has low operating costs (solar energy, less fuel required for additional heating), and less skill is required than for conventional kiln drying

1.4.2 Disadvantages

· Solar Kiln is more normally more expensive then air drying.

· More skill is required to them well.

· Require maintenance.

· Solar kilns depend on weather conditions (affected by rain, cloudy days)

Overall solar kiln is considered as an acceptable alternative to air-drying method for pre-drying of hardwoods (e.g. black butt, Eucalyptus pilularis).
So Australasian timber industry is showing an increasing interest in use of solar kilns.Solar kilns are ineffective for high production shops, but they certainly have their place with serious hobbyists and individual furniture and cabinetmakers.

Chapter 2

LITERATURE REVIEW

2.1 Background

The earliest known kiln dates to around 6000 BC, and was found at the Yarim Tepe site in modern Iraq. As air is heated in the collector space, one or more fans circulate it through the lumber, enabling it to absorb moisture from the lumber’s surface. When the evaporated moisture increases the relative humidity to where it gets too high in the chamber, it releases it through vents in the back of the kiln. Solar Kilns Managing Director, Greg Weir, is a second-generation Australian saw-miller and timber processor with over 40 years’ experience in sawmill and timber processing industry. The original model of this dryer was successfully built and used for years by Curtis Johnson, a retired Forest Service employee. A newer model designed by Mr. Johnson with greater holding capacity and other improvements is now in operation. Steinmann (1992) investigated the effects of collector area and solar tracking on the performance of a solar wood drying kiln and came to the following conclusions: Increasing the collector ratio (collector area per volume wood in the kiln) from 2.4 to 12.1 m²/m ³ raised the average temperature by only 2°C, over the full drying time. The solar simulation system as previously described (Steinmann 1990) was used to simulate an actual drying run in a solar kiln. Adjustments necessary to compensate for difference in scale are described. The simulated weather conditions were in close agreement with the actual weather. [9]

Solar-kiln drying gives a higher quality of seasoned timber than open-air seasoning (Johnson, 1961). [1] The main types of solar kiln include: the greenhouse type-(Plumptre, 1979), semi-green-house (Young, 1979) and solar kiln with external collector (Tschernitz & Simpson, 1979; ofi, 1982) [1]. The objective of this work was to construct and test the performance of the simple solar kiln designed for small-scale sawmills in tropical countries [Plumptre, R. A. (1983).[4] Some thoughts on design and control of solar timber kiln. Paper presented to Wood Drying Workshop of IUFRO Division V Conference, Madison, WI]. The solar kiln reduced the drying time of Terminalia Superba and Mansnia altissima by a third when compared with the open-shed during the wet season (May-July) this is reasonabily high when compared with earlier reports of dryers [Off, 1982; Duffle et al.,1974].[5]

The model was validated experimentally for a box-type collector solar kiln operating under constant and falling rate drying periods. It was found that although the model could be applied satisfactorily, the tested design proved to be a very inefficient one, giving low values for the recirculating parameter.

The flow diagram illustrating the control logic of this kiln is published elsewhere (Steinmann, Vermass 1990). The moisture content of the kiln air, expressed as equilibrium moisture content (EMC), was controlled according to a normal drying schedule based on the instantaneous moisture content of the load. The control logic satisfied the following two conditions:

· Venting was allowed only if EMC(I)>EMC(P) where EMC(P)= the target value for the equilibrium moisture content inside the kiln [EMC (I)], according to the drying schedule.

· Venting should produce a net moisture loss in the kiln air.

The temperature and equilibrium moisture content of the air inside and outside the kiln were measured and recoded at 5-min intervals, together with the solar radiation, mass of the Kiln and air dryir loads, frequency of venting as well as spraying, and the time, recorded by computer.[5]

2.1.1 Formulation:

Ø Governing equations:
Referring to Fig. 1, let x be the vertical distance along the solid layer measured from the layer base. Assuming a one-dimensional model, constant properties of solid and air, spherical solid particles, well insulated kiln, and plug flow, the energy balances for air and solid in a control volume of thickness dx give, respectively, the following:

Ø Initial and boundary conditions:
The previous governing equations are subject to the following initial conditions :
t <<.O, T~= T~.~, T. = T.. (3)
The boundary condition for T~at t > 0 and x = 0 is

and that for air is
p,, K, eACp~,(T,, - T~ )x=o = h(1 - OA(T, - T~ ).,- o
which gives.

The boundary condition for T~at t > 0 and x = 3 is h(l -e,)A(To- L).,.~,~+ (1 -~)Ad:~

where To is the temperature of the air above the layer. Also, the heat balance of the air leaving the layer gives

p~v~d;ACp~(To- T,,)., ,~ = h ( 1 - e ) A ( T ~ - - To), ~. (6b)
Equations (6a) and (6b) give

Which is the boundary condition for T~ at t > 0 and X~ (~.

Ø Air velocity:

The air flow in the solar kiln is caused by natural draft due to the temperature difference in the kiln and the ambient temperature. The pressure difference available for a draft of air is.

where the superscript "*" means at x = 6. The dependence of p~ on Ta at constant pressure is expressed as follows.

The pressure drop in the air flowing across the solid layer depends on layer thickness and air velocity. For various crops and pebble beds, the air velocity is assumed to be related to the pressure drop per unit depth of the solid layer according to the following expression.

where K and n are constants that depend on the dimension and type of the solid material. Using eqs (7-9), the expression for the air velocity becomes

Ø The dimensionless equations;

The governing equations, eqs (1) and (2), are transformed to the following equations.

where cq, ~2, ~3, and ~4 are dimensionless parameters defined as

The expression for V~given by eq. (10) also becomes

The dimensionless form of the initial and boundary conditions take the following form:

Ø The finite difference equations:

The finite difference technique is used to solve the governing equations together with their boundary conditions. An implicit method is used with the Gauss-Seidel iterative technique. Computer search is carried out to determine the space step AX and time step AT that give a unique solution which is independent of the reduction in AX and Az. A convergence criterion that the relative variation in the temperature of any nodal point should be less than 10 - 6 is used between any two successive iterations. A summary of the finite difference equations is given in the Appendix.

2.2 Solar kiln construction

The solar kiln described by Steinmann et al. ( 1980, 1981 ) consisted of an insulated chamber and an external collector facing north and inclined at 45 ° to the horizontal (latitude of the kiln site + 10°) for optimum year round performance. Air was circulated over the collector and through the load at 1.7 m/sec -¹. Vents and a spray system were used to control the relative humidity in the kiln. The temperature and relative humidity of the air inside and outside the kiln, the mass of the kiln load, the status of the venting system (open/closed), the moisture content of the kiln load, the time of the day, and the solar radiation were recorded at 15 min intervals.

Figure 3 SOLAR KILN FRONT VIEW. [10]

Ø Solar kiln control:

In conventional kilns, drying is controlled according to drying schedules. These specify the temperature and relative humidity of the kiln air at any given wood moisture content value. In a solar kiln, the maximum temperatures are approximately 50°C, last only for very short periods during each day, and are only achieved when the wood is partially dry and can endure these temperatures. Temperature control is not necessary in solar wood drying kilns and, therefore, only the moisture content of the kiln air has to be controlled according to the given drying schedule. The relative humidity inside the solar kiln was computer controlled in such a way that venting was only allowed if it rose above the target value as given by the drying schedule and if, at the same time, the absolute humidity of the outside air was less than the absolute humidity of the air inside the kiln. If both conditions were not satisfied simultaneously, venting was not allowed. This was to prevent air with too high a moisture content from entering the kiln. With this control, venting was optimized, preventing loss of energy. Such a system would achieve identical drying results using the same drying schedule under the same weather conditions both in the solar kiln and the SS.

Ø The simulation system:

· Design:
The SS (Fig. 1) consisted of a commercial CC into which a SKS (Figs. 2 and 3) was placed. The mm long and with the same cross section as the lumber used in the solar kiln, comprised the SKS load. SKS was controlled in exactly the same way as the solar kiln. A single piece of wood, 500

Ø Weather simulation

The temperature and relative humidity of the air outside the solar kiln could be accurately simulated on a real-time basis in the CC. The solar energy input to the SKS was simulated by a power transistor (50 watt max) mounted on a finned heat sink, serving as the collector plate. This collector plate was placed inside the SKS parallel and next to the window (Fig.1) allowing for the long wave radiation losses that occur in a collector. The glass area of the window could be adapted to simulate changes in collector area.

The energy input, W (in watts/m-2), under the glass cover of the solar kiln collector was calculated using eqn (1) which is based on equations described by Kreider and Kreith ( 1975 ) and Lunde (1980). The input data consisted of the solar radiation recorded during a specific solar kiln run, taking into account the angle of incidence, (i) of the solar radiation on the inclined collector, and the fraction (P) of the radiation passing through the glass cover of the collector at different angles of incidence. These values were multiplied by the collector area, a, (m 2) as simulated in the SKS. These calculated W values represent the target values for the output of the transistor on the collector plate in the SKS and were stored together with the ambient temperature and relative humidity values as obtained from the same solar kiln run to serve as target values for the control of the CC (weather simulator).

Where la = solar intensity on a surface perpendicular to the radiation at any selected date and time; i = angle of incidence between the solar radiation and the collector surface at any selected date and time; and P is calculated according to eqn (2) below. The fraction, P, of the radiation passing through the glass cover of the collector, was measured for the 5 mm thick glass cover of the solar kiln at different angles of incidence (i) using a solar meter. At i = 90 ° the radiation under the glass was taken as zero.

Equation (2) gives the empirically determined mathematical relation t between P and i.

where

Ø Conclusions

From the above evidence it was concluded that the simulation system could produce real and repeatable drying results and that meaningful real-time simulations are possible using this equipment. Using this simulation system, Steinmann (1992) investigated the effects of collector area and solar tracking on the performance of a solar wood drying kiln and came to the following conclusions:

Increasing the collector ratio (collector area per volume wood in the kiln) from 2.4 to 12.1 m²/m ³ raised the average temperature by only 2°C, over the full drying time. Maximum kiln temperatures were 10°C higher, but the minimum temperatures were not increased being a function of the ambient night temperature. Increasing the collector ratio from 2.4 to 7.3 m2/m 3 reduced the drying time by about 20%, but further increases in collector ratio produced no further improvement. At a kiln site with latitude 35 ° or higher, solar tracking by the collector doubles the daily collected energy, but has no effect in winter. Solar tracking by the collector can reduce drying times in summer by between 13% and 21%. Solar tracking about a vertical axis, with seasonal adjustments of the collector angle with the horizontal axis, reduces the drying times as much as full tracking.

2.3 Components

1. Vent Fan and Fan Motor

2. Test Piece Led Vent

3. Dry Bulb and Relative humidity Sensor

4. Load cell and window

As wood is a hygroscopic material, it will adsorb moisture from, or lose moisture to, the surrounding air until its moisture content is in equilibrium with the surrounding air.

2.4 Mechanism

Solar energy is the basic resource needed in the wood drying process of this Kiln. Temperature of Kiln is increased with the absorption of sun heat into the kiln the entry of heat energy of the sun take place from glazed clear screen and is readily taken by the dark black internal chamber.

The solar kiln consist collector chamber where all the heated air is collected. Fan running with help of electric power are used as tool for circulating the air across the timber chamber. This process enables the heated air to evaporate the water from wood and absorb it in the air itself. As a result of this absorption the humid element of the air keep on increasing. When the chamber the certain high level of humidity an automatic exhaustion process initiated where by the hot humid air thrown out of the vents located of rear portion the solar kiln.

2.4.1 Enhance size solar kiln material

To enhance the size of the solar kiln to understand that the basic ratio principle for each 10 board feet of wood you will need a 1 square panel of the solar energy for clear roof of the top of kiln number an area of solar screen is of almost importance of the solar kiln if the area is to large it can cause over drying or speeding up of the wood drying process. This may result in cracking in splitting of timber. Similarly if the solar screen area is too little, it can result in slow drying or even no drying at all because the required heating temperature of the air will not be reached.

2.4.2 Significant of solar kiln angle

Significance feature of Solar Kiln design is the angle of its roof this angle should be such that able to absorb right amount of sun light from sun. The angle can be determined by using the latitude of the place where the kiln will be placed for wood drying. The angle of solar panel or roof should be modified according to movement of sun in different time of year.

2.4.3 Energy measuring

.As kiln temperatures are usually higher than ambient temperatures; energy is lost from a kiln. These losses Are at a maximum when {T (I) - T (O)} is at a maximum and this is the case when T (I) reaches its peak value. [10]

. The temperature and humidity be observed on a working drying time.

. All features are depends upon weather condition.

2.4.4 The circulation system

Wood drying required an equal distribution of hot air throughout the drying chamber it’s therefore very important to have some circulation mechanism in place for movement of the hot air from the absorption area to the other parts of the in most of the solar kiln design electric fans are installed at place which the highest temperatures this allow the highest amount of heat transfer within the circular chamber

Figure 4 Air circulation system. [12]

2.5 Solar kiln

There are several types of solar kilns, but they all generally rely on some type of solar collector to provide the heat energy that evaporates the water in the lumber. Unlike solar heating for an office or home, in lumber drying it’s not possible to reduce the heat requirement to the point where solar heating can be competitive. When you’ve got a certain amount of water to remove from a certain amount of wood, you need a certain amount of total heat to do it, and that heat requirement can’t be changed.

Figure 5 Solar Kiln.[14]

Types of solar kiln design

All through the basic design of a Solar Kiln remains that same some variation can divide it into different design forms a few of them are provided below.

2.5.1 Compartment kilns design

Compartment-type kilns are designed for a batch process in which the kiln is completely loaded or charged with lumber in one operation, and the lumber remains stationary during the entire drying cycle. Temperature and relative humidity are kept as uniform as possible throughout the kiln, and they can be closely controlled over a wide range of temperature and humidity.

2.5.2 The greenhouse kiln design

This is the basic form solar kiln design based on greenhouse design it has a large chamber like a greenhouse in contains a transparent screen with glazed on the top roof. It is surrounded by three walls on side accept the north. The transparent screen is made up of plastic material. This type of kiln loses a lot of heat energy from collector walls and the plastic which is poor insulator. Therefore some time manufacturers use double glazing sheet on the solar panel on the screen.

2.5.3 The semi-greenhouse design

This type of solar kiln design contains one glazing screen on a roof and one on the southern wall. All the other wall are totally opaque and do not let the heat pass through them .they are made from highly insulating materials.as a consequence the loss of heat energy from this type of solar kiln is minimized it is mostly made from a wooden frame of play wood material .the collector of semi greenhouse designed kiln is one of the most vital components of a system.

chapter 3

3.1 DESIGN PARAMETERS

Figure 6wood chamber of solar kiln

3.2 Solar kiln

The Width of Solar Kiln is = 1.5 Feet.

The Length of Solar Kiln is = 2.5 Feet.

The Height of Solar Kiln is = 2.0 Feet.

3.3 Acrylic sheet

Acrylic Sheet which we put on sides of the Kiln is = 2 mm thickness.

Acrylic Sheet which we put on Top of the Kiln is = 1.5-2mm thickness.

3.4 Temperature & humidity of the solar kiln

· Humidity in summer is = 60 to 80 %

· Temperature in summer is = 40 ⁰C

· Humidity in winter is = 40 to 70 %

· Temperature in winter is = 7⁰C to 30⁰C

3.5 Fan (two sets)

· Four Blades Fan, (As increasing number of Blades, Efficiency is also increases).

· Fans; micro blades, which is generally use in computer system.

3.6 Solar kiln design Volume Calculation:

Figure 8 rectangular shape of Solar Kiln

Figure 9 triangular shape of the Solar Kiln

From the figure (8&9) we can find out total volume and area of solar kiln chamber:

For volume= V₁

V₁= width× length× thickness

V₁=_.724m×.305m×.419m

V₁= 0.0925 m³

For volume =V₂

V₂= ½ (.419m) (.724m) (.305m)

V₂=.04625m³

Therefore total volume of the Solar Kiln

V_Total=V₁+V₂

V_Total= (.0925m³) + (.04625m³)

V_Total=13785m³

Now density of Sisso (tree) δ=800kg/m³

δ =m/v therefor m=δ× v

m= (.13875m³) (800kg/m³) = 111kg

Total mass capacity of Solar Kiln for Sisso (tree)

m_Total = 111kg

3.7 Drying days (wood & crops)

Minimum 6 to 13 days, but if we want more better result than 45 days are maximum period. Wood seasoning depends on wood quality types for example Kail tree and Parthal tree. Kail trees are mostly used for doors and window whereas Parthal also used for doors and window, for industrial purpose.

· Capacity of wood chamber is = 111kg (Peak-volume) of lumber.

· 4 to 6 board piece of (wood) length and thickness, 24 inch 1.2 inch and width is 12inche respectively.

· We not interested to finding, the wavelength of the sun light which is passing through Acrylic Sheet, and Sun light is 1000 Wabers per square meter.

3.8 Solid work

Figure 10 front view of solar kiln

Figure 11 back view solar kiln

Figure 12 side view of Solar Kiln

Figure 13 top view of Solar Kiln

chapter 4

FABRICATION OF SOLAR KILN

4.1 Fabrication:

Solar Kiln fabrication is the building of Wood (lasani) structures by cutting, joints, and assembling processes. It is a value added process to achieve the wood Chamber by cutting wood and Acrylic Sheet. Cutting (machine wood) and Hand Saw use in manufacturing of Solar Kiln:

Ø Cutting (wood machine).

Ø Hand saw.

4.2 Cutting (wood machine) process:

Sheets (Lasani & Acrylic) available in market are in different sizes as compare with our required size so cutting machine used for cutting sheet for required shapes. Usually, measured the point where the cutting action takes place and perpendicular to the direction of blade movement.

Figure 14 wood cutting machine

4.3 Hand saw:

It is simple way to cutting the wood (Lasani) by human effort. By utilizing human force energy to achieved the required objective. The picture above is the picture of the handsaw and as we all know handsaw's go back in history a long ways. Your grandfather or great-grandfather's use handsaw is to build most of their projects before power tools.

Figure 15 Hand-saw

4.4 Joint process:

In this type of joint process we add Wood lasani & Acrylic Sheet to the joint and prepared the simple Solar Kiln chamber. Used for joining for following parts

Ø Wood Lasani

Ø Acrylic sheet

Figure 17 acrylic sheet

4.5 Material:

We are using wood sheet & Acrylic sheet for fabrication of different parts of Solar Kiln chamber.

Their main properties are given

Ø Wood chamber

Ø Acrylic sheet

4.6 Tool and instrument used:

Ø Vernier caliper

Ø Measuring tape

Ø Hammer

4.7 Components:

Acrylic Sheet
Fans (two-sets) and Relay Control
Humidity and Temperature Sensor
Arduino UNO
LCD Display (16×2)
Battery (12V)
Insulation Sheet

4.8 Acrylic sheet:

The acrylic sheet is ceramic material with high temperature capability. Acrylic Sheet change the Sun Light wave length, when sun light passed through it. Clear cast acrylic, also commonly referred to as Perspex Sheet, is a high quality and versatile clear plastic sheet material offering high levels of strength and clarity. Suitable for many applications, cast acrylic sheet is an easy material to work with.

Cast acrylic is one of the hardest thermoplastic sheet materials available and its attractive aesthetics remain for longer than other plastic sheet materials. Cast acrylic is manufactured by pouring monomer between two sheets of high quality glass and polymerized in batches in a carefully controlled manufacturing process; Clear cast acrylic has an exceptionally high level of light transmission allowing 92% of all visible light through the material creating an unparalleled crystal clear finish. Not even glass can achieve this level of optical clarity. Because of this clear cast acrylic is an excellent alternative to glass for glazing purposes.

4.9 Fans (two-sets) and relay control:

Fan used as exhaust of Air. We used dc-fan in the Solar Kiln project Relay Control used as ON/OFF switch.

Figure 19 fan

4.10 Humidity and temperature sensor:

$Description: C:\Users\Elitebok\Desktop\20170214_210001_IMAGE\20170214_180452.jpg$ Humidity is the presence of water vapor in air. The amount of water vapor in air can affect human comfort as well as many manufacturing processes in industries. One of the tasks of air-Exhausting, depending on the existing internal and external effects, is to provide optimal temperature in the Solar Kiln. Temperature sensors are integral components of Solar Kiln units.

4.11 Battery:

Dc-battery (12volt) rechargeable li-ion 6000mah pack for lcd, humidity & temperature sensors, a rechargeable battery, storage battery, secondary cell, or accumulator is a type of electrical battery which can be charged, discharged into a load, and recharged many times, while a non-rechargeable or primary battery is supplied fully charged, and discarded once discharged. it is composed of one or more electrochemical cells. the term "accumulator" is used as it accumulates and stores energy through a reversible electrochemical reaction. Rechargeable batteries are produced in many different shapes and sizes, ranging from button cells to megawatt systems connected to stabilize an electrical distribution network. several different combinations of electrode materials and electrolytes are used, including lead–acid, nickel cadmium (nicd), nickel metal hydride (nimh), lithium ion (li-ion), and lithium ion polymer (li-ion polymer).

Rechargeable batteries typically initially cost more than disposable batteries, but have a much lower total cost of ownership and environmental impact, as they can be recharged inexpensively many times before they need replacing. some rechargeable battery types are available in the same sizes and voltages as disposable types, and can be used interchangeably with them. [11]

4.12 Insulation:

Insulation is to protect every system from damage. This way here we use it for to not direct effect the weather condition on the system of Solar Kiln. Knauf Insulation Black Acoustical Board with ECOSE® Technology is designed for use as acoustical insulation and/or a visual barrier on walls and ceilings, where system design requires a rigid product and where additional strength and abuse resistance are required. The black surface provides a visual barrier with an aesthetic appearance, in both wall and ceiling applications. The product is typically used where framing members are not present.

4.13 ARDUINO UNO:

There are a number of different Arduino boards; we will be using one of the most popular, the Arduin Uno. The Arduino Uno has a number of input ports which can be used to read a signal from other Sensor and Fan, and output ports which can be used to drive external lights, speakers, motors and LCD. Arduino/Genuino Uno is a microcontroller board based on the ATmega328P (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz quartz crystal, a USB connection, a power jack, an ICSP header and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. You can tinker with your UNO without warring too much about doing something wrong, worst case scenario you can replace the chip for a few dollars and start over again.

Figure 22 ARDUINO UNO

4.14 Lcd display (16×2)

In this project we are using LCD for to show us humidity and temperature respectively. It has 16 column and 2 rows. We need to solder the header pins to the LCD display,the header pins i have are 2.0mm and you need the 2.5mm pins to fit the LCD display, so mine didn't fit because they were to close together, so i decided to cut my header pins into groups of 2,after i cut them into groups of 2, i could put 1 group of 2 in 2 pins, when you insert them, turn the display over and apply a small amount of solder to each terminal, ensuring that all the terminals are soldered, they should all be the same length, not bent, loose or too short.

Figure 23 lcd display (16×2)

4.15 Assembly:

We assemble all parts together by joints. And nails are used to supports together two joints. The ends of the wood were painted with leftover stain to reduce over-drying of the wood near the ends. The wood is stacked in the kiln with spacers between the boards called stickers. I stapled some Tyvek cloth between the bases of the metal panels and laid it across the top of wood stack to direct air through the stack. Concrete blocks were also placed on the wood to reduce any wood bending.

4.16 Complete assembly of solar kiln

It’s important to locate the kiln with a south-facing exposure that’s free of shadows. I set down treated landscape timbers to hold the kiln up off the ground (Photo 1). The timbers provide a level platform for the kiln to rest on. we started by securing the floor to the timbers, then added the back and sides . After attaching the fan plenum to cleats mounted on the side panels, we drilled a hole for the fan cord. Finally, the kiln was ready for loading. All we needed was some green wood to dry.

Figure 24 complete Assembly

chapter 5

5.1 EXPERIMENTATION AND RESULTS

5.2 For the first day experimental value

Table 1

Experiment Time PM	Time in mints	Ambient temperature	System temperature	Ambient Humidity	System Humidity	Fan On Time	Number of Experiments
1:30	30 mints	25 C⁰	47.32 C⁰	27.5%	22%	3:12 second	01
2:00	30 mints	25 C⁰	46.69 C⁰	33.12%	20.26%	2mints	02
2:30	30 mints	26 C⁰	46.12 C⁰	24.11%	18.96%	3:34 second	03
3:00	30 mints	26 C⁰	47.32 C⁰	31.63%	17.26%	2:34 second	04

5.3 For the second day experimental values

Table 2

Experiment Time PM	Time in mints	Ambient temperature	System temperature	Ambient Humidity	System Humidity	Fan On Time	Number of Experiments
1:30	30	29 C⁰	49.32 C⁰	21.5%	22.23%	3:16 seconds	01
2:05	30	27.7 C⁰	46.13 C⁰	20.5%	18.12%	3:00 mints	02
2:40	30	26 C⁰	47.87 C⁰	22.5%	17.87%	1:35 seconds	03
3:10	30	25 C⁰	48.32C⁰	21.5%	16.92%	2 mints	04

5.4 Results of two days experiments:

We put total 10.6kg Wood tiles in solar kiln for wood seasoning, As wood is a hygroscopic material, it will adsorb moisture from, or lose moisture to, the surrounding air until its moisture content is in equilibrium with the surrounding air.

5.4.1 On first day:

In the start of experiment, the weight of wood was 10.6 kg. After two hours due to loss of humidity the weight of wood we weighed was 10 kg. We observed that for 2 hours, the loss of weight of wood was 0.6 kg.

5.4.2 On second day:

In the start of experiment, the weight of wood was 10 kg. After two hours due to loss of humidity the weight of wood we weighed was 9.5 kg. We observed that for 2 hours, the loss of weight of wood was 0.5 kg

CHAPTER 06

SAFETY AND HAZARDS

Any organization cannot survive without any safety consideration. It is very important for an organization to safeguard the health and welfare of its employees and the general public. Safety should be in good practice; the good management practices needed to ensure the safe operations in the organization that has an impact of efficient operations. The term loss prevention refers having loss in financial caused by an accident. This loss is not only considered by replacing the cost of damaged plant and third party claims, but also the loss of earnings from lost production and lost sales opportunity.
All manufacturing processes are to some extent hazardous, but in chemical processes there are no. of hazards associated with the chemicals, equipment’s and operations. The designer must be aware of these hazards, and ensure, through the application of sound engineering practice, that the risks are reduced to acceptable levels.

6.1 Sources of sun-light on Acrylic sheet:

Precautions must be taken in order to eliminate sources of sunlight on Acrylic Sheet to the wood chamber. It is best way to work on the principle of flammable material like oil wood or other agricultural products etc.

6.2 Electrical equipment:

The sparking of electrical equipment, such as temperature and humidity sensor and lcd , arduino uno, is a major potential source of ignition, and flame proof equipment is normally specified. Electrically operated instruments, controllers and computer systems are also potential sources of ignition of flammable mixtures.

6.3 Vent Air:
When designing relief venting systems it is important to ensure that flammable or temperature and humidity are vented from wood drying chamber. This will normally mean venting at a sufficient rate values of temperature and humidity that prevents solar kiln from squeezing.

6.1.5 Temperature deviations:
Temperature deviations can cause a major accident in any plant operation. Excessive high temperature can cause structural failure and initiate disaster. High temperature can cause wood cracks.
The protection can be taken to avoid high temperature by:

1. Provision of high-temperature alarms and electronics controls devises to overcome the high temperature and humidity.
2. Provision of emergency cooling systems for solar kiln wood chamber, where heat continues to be generated after shut-down; for instance, in some polymerization systems.
3. Structural design of equipment to withstand the worst possible temperature excursion.
4. The selection of intrinsically safe heating systems for hazardous materials.

conclusion

In solar kiln we try to save the wood from the damage and cracks
In solar kiln we dry the wood as fast as we can.
We maintain the temperature and humidity of solar kiln from giving the specific range.
In cold weather the dryness of wood is difficult so with the help of solar kiln we easily dry wood
Drying times were 3 to 4 months from initial (43 to 62%) to final MC (12 to 22%).

Recommendations for Future work
Based on the present study the following recommendations are made for future study
1. The produced seasoning of wood or agricultural products should be used for furniture’s etc.

2. All of the above scope of study we can say that wood and agricultural products are mostly used for homes offices and industrial uses for burning.

Summary

Solar kilns are ideal for the hobbyist or professional woodworker who wants to save money by drying his own lumber. Solar kilns are relatively inexpensive to build and simple to operate. They use the free energy of the sun, so they cost nothing to operate except for the small cost of electricity needed to run the fans. Additionally, they are good for the environment since they generate zero CO² emissions.

Although solar kilns are designed to keep the wood from drying too rapidly, it is wise to check the MC level, especially near the end of the drying cycle. It’s also recommended that woodworkers who are new to drying lumber in a solar kiln or who are drying wood thicker than one inch frequently check the moisture levels to prevent defects later on. A moisture meter is a woodworker’s best insurance for solar-dried lumber to prevent cracking, warping, or splitting in the finished wood product.

references

[1] ADNAN H. ZAHID and MOUSTAFA M. ELSAYED August 1988.& http://owic.oregonstate.edu/solarkiln/plans.htm

[2] D. E. STEINMANN*Department of Wood Science, University of Stellenbosch, Private Bag X5018, Stellenbosch, 7599, South Africa.

[3] Dr wengret 1978 Spa Depot, spadepot.com, 800-823-3638, Outdoor Electronic 24-Hour Timer w/ Single Outlet, #BX9982.

[4] By Duffle, Y. A. & Beckman,. (1974) in New york.

[5] D. E. Steinmann Department of Wood Science, Faculty of Forestry, University of Stellenbosch, Stellenbosch 7600, South Africa.

[6] D. E. Steinmann Department of Wood Science, Faculty of Forestry, University of Stellenbosch, Stellenbosch 7600, South Africa.

[7] R. M. Polak, L. L. Christianson and M. A. Hellickson,Grain drying with a solar energy intensifier—simulation and validation. ASAE Technical paper 81-3517 (I981).

[8] Kreider, J. F., and Kreith, F., Solar heating and cooling, McGraw-Hill, New York (1975).

[9] Steinmann, D. E., The effect of collector area and solar tracking on the performance of a solar lumber drying kiln. Proceedings 3rd IUFRO International Wood Drying Conference, Vienna, Austria, 283-291 (1992)

[10] http://www.sciencedirect.com/science/article/pii/0038092X9400135Z.

[11] www.nyle.com/downloads/KilnDrying.pd.

[12] http://mendoncottagebooks.com. (drying wood with solar Kiln).

[13] http://www.knaufinsulation.us/en/content/black-acoustical-board

Abbreviation

EMC=Equilibrium Moisture content.

SSS= Solar system simulation.

SKS= Solar Kiln simulation

CC= climate chamber.

control Solar Kiln with help of arduino uno

1.2.6 Battery

1.2.7 Insulation

1.3 Exhausting fan and ambient air inlet

1.3.1 Exhausting fan

1.4.1 Advantages

1.4.2 Disadvantages

2.1 Background

2.2 Solar kiln construction

2.3 Components

4.3 Hand saw:

4.5 Material:

4.6 Tool and instrument used:

4.7 Components:

4.8 Acrylic sheet:

4.10 Humidity and temperature sensor:

4.12 Insulation:

5.2 For the first day experimental value

6.1 Sources of sun-light on Acrylic sheet:

conclusion

Abbreviation

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