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http://www.iaeme.com/IJCIET/index.asp 365 [email protected] International Journal of Civil Engineering and Technology (IJCIET) Volume 9, Issue 8, August 2018, pp. 365377, Article ID: IJCIET_09_08_037 Available online at http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=9&IType=8 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 © IAEME Publication Scopus Indexed OPTIMIZATION OF THERMAL COMFORT IN OFFICE BUILDINGS USING NON-TRADITIONAL OPTIMIZATION TECHNIQUES S. Elizabeth Amudhini Stephen Associate Professor of Mathematics, Karunya Institute of Technology and Sciences, Coimbatore, India ABSTRACT Due to the difficulty of controlling the indoor thermal environment, it is important to provide thermal comfortable conditions which meet occupants’ expectation. In order to realize the long-term thermal comfort in indoor environment, the microclimate in Karunya university campus in Coimbatore, Tamilnadu. India is measured through year. PMV model is applied to calibrate the climate parameters and environment elements .The results obtained are optimized using ten different nontraditional optimization models and compared to find which method is suitable in terms of number trails and minimum time taken. ASHRAE standards are verified. Key words: Indoor Thermal Comfort, Hot-Humid Regions, Non-traditional Optimization Techniques. Cite this Article: S. Elizabeth Amudhini Stephen, Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques. International Journal of Civil Engineering and Technology, 9(8), 2018, pp. 365-377. http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=9&IType=8 1. INTRODUCTION Thermal comfort is highly subjective, not only is it subject to personal preference but also to varying temperatures. Both internal and external temperatures sensing is integrated in such a way that the resulting effect would either move towards restoring deep body temperature or move away from it. A cold sensation will be pleasing when the body is overheated, but unpleasant when the core is already cold. At the same time, the temperature of the skin is by no means uniform. Besides variations caused by vasoregulation, there are variations in different parts of the body, which reflect the differences in vasculation and subcutaneous fat. The wearing of clothes also has a marked effect on the level and distribution of skin temperature. Thermal comfort for human is one of the major problems at present. Providing thermal comfort for occupants in buildings is really a challenging task because thermal comfort is not

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Page 1: OPTIMIZATION OF THERMAL COMFORT IN OFFICE BUILDINGS … · Thermal comfort can be calculated by an equation called Fanger‟s „Predicted Mean Vote‟ (PMV) as given by Fanger. This

http://www.iaeme.com/IJCIET/index.asp 365 [email protected]

International Journal of Civil Engineering and Technology (IJCIET)

Volume 9, Issue 8, August 2018, pp. 365–377, Article ID: IJCIET_09_08_037

Available online at http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=9&IType=8

ISSN Print: 0976-6308 and ISSN Online: 0976-6316

© IAEME Publication Scopus Indexed

OPTIMIZATION OF THERMAL COMFORT IN

OFFICE BUILDINGS USING

NON-TRADITIONAL OPTIMIZATION

TECHNIQUES

S. Elizabeth Amudhini Stephen

Associate Professor of Mathematics,

Karunya Institute of Technology and Sciences, Coimbatore, India

ABSTRACT

Due to the difficulty of controlling the indoor thermal environment, it is important

to provide thermal comfortable conditions which meet occupants’ expectation. In

order to realize the long-term thermal comfort in indoor environment, the

microclimate in Karunya university campus in Coimbatore, Tamilnadu. India is

measured through year. PMV model is applied to calibrate the climate parameters

and environment elements .The results obtained are optimized using ten different

nontraditional optimization models and compared to find which method is suitable in

terms of number trails and minimum time taken. ASHRAE standards are verified.

Key words: Indoor Thermal Comfort, Hot-Humid Regions, Non-traditional

Optimization Techniques.

Cite this Article: S. Elizabeth Amudhini Stephen, Optimization of Thermal Comfort

in Office Buildings Using Non-Traditional Optimization Techniques. International

Journal of Civil Engineering and Technology, 9(8), 2018, pp. 365-377.

http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=9&IType=8

1. INTRODUCTION

Thermal comfort is highly subjective, not only is it subject to personal preference but also to

varying temperatures. Both internal and external temperatures sensing is integrated in such a

way that the resulting effect would either move towards restoring deep body temperature or

move away from it.

A cold sensation will be pleasing when the body is overheated, but unpleasant when the

core is already cold. At the same time, the temperature of the skin is by no means uniform.

Besides variations caused by vasoregulation, there are variations in different parts of the body,

which reflect the differences in vasculation and subcutaneous fat. The wearing of clothes also

has a marked effect on the level and distribution of skin temperature.

Thermal comfort for human is one of the major problems at present. Providing thermal

comfort for occupants in buildings is really a challenging task because thermal comfort is not

Page 2: OPTIMIZATION OF THERMAL COMFORT IN OFFICE BUILDINGS … · Thermal comfort can be calculated by an equation called Fanger‟s „Predicted Mean Vote‟ (PMV) as given by Fanger. This

S. Elizabeth Amudhini Stephen

http://www.iaeme.com/IJCIET/index.asp 366 [email protected]

only influenced by temperature but also factors like relative humidity, air velocity,

environment radiation, and activity level and cloths insulation. These entire six variables play

a major role in providing thermal comfort.

Thermal comfort can be calculated by an equation called Fanger‟s „Predicted Mean Vote‟

(PMV) as given by Fanger. This equation gives the optimal thermal comfort for any activity

level, clothing insulation and for all combinations of the environmental variables such as air

temperature, air humidity, mean radiant temperature and relative air velocity.

Human thermal comfort is defined by ASHRAE as the state of mind that expresses

satisfaction with the surrounding environment (ASHRAE Standard 55). Maintaining thermal

comfort for occupants of buildings or other enclosures is one of the important goals of design

engineers.

Thermal comfort is maintained when the heat generated by human metabolism is allowed

to dissipate, thus maintaining thermal equilibrium with the surroundings. Any heat gain or

loss beyond this generates a sensation of discomfort.

It has long been recognized that the sensation of feeling alone. The problem that we are

going to deal with here is the thermal hot or cold is not just dependent on air temperature

comfort of offices .

2. LITERATURE SURVEY

Human perception of air movement depends on environmental factors such as air velocity, air

velocity fluctuations, air temperature, and personal factors such as overall thermal sensation,

clothing insulation and physical activity level (metabolic rate) (Toftum, 2004). Air velocity

affects both convective and evaporative heat losses from the human body, and thus

determines thermal comfort conditions (Tanabe, 1988; Mallick, 1996). If we agree that

thermal environments that are slightly warmer than preferred or neutral, can be still

accepTable to building occupants as the adaptive comfort model suggests (deDear, Brager,

2002; Nicol, 2004), then the introduction of elevated air motion into such environments

should be universally regarded as desirable. This is because the effect will be to remove

sensible and latent heat from the body, so body temperatures will be restored to their comfort

set-points. This hypothesis can be deduced from the physiological principle of alliesthesia

(Cabanac, 1971).

In hot and humid climates, elevated indoor air velocity increases the indoor temperature

that building occupants find most comfortable. Nevertheless, the distribution of air velocities

measured during these field studies was skewed towards rather low values. Many previous

studies have attempted to define when and where air movement is either desirable or not

desirable (i.e. draft) (Mallick, 1996; Santamouris, 2004).

Thermal comfort research literature indicates that indoor air speed in hot climates should

be set between 0.2 - 1.50 m/s, yet 0.2 m/s has been deemed in ASHRAE Standard 55 to be the

threshold upper limit of draft perception allowed inside air-conditioned buildings, where

occupants have no direct control over their environment (de Dear, 2004) The new standard 55

is based on Fanger‟s (1970) draft risk formula, which has an even lower limit in practice than

0.2 m/s. None of the previous research has explicitly addressed air movement acceptability.

Instead it has focused mostly on overall thermal sensation and comfort (Toftum, 2002).

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Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques

http://www.iaeme.com/IJCIET/index.asp 367 [email protected]

3. RESEARCH METHODS

3.1. Outdoor Climatic Environment

Under the Koppen climate classification, the Coimbatore city has a tropical wet and dry

climate. It has mild winters and moderate summers. Karunya University office buildings lie in

the latitude of 100 55‟ 51.73” N and longitude of 760 44‟ 40.60” E with elevation 1551 ft. The

surveys in this study were performed in the May 2009 and September 2009

3.2. Subjects

A Sample size of 220 subjects in 8 different office buildings in the Karunya University was

collected in survey and field measurements. The offices interviewed are multi-story buildings.

The volunteers participating in the study comprised both men and women. The average age of

all respondents was 33.2 years, ranging from 23 to 57 years. All the participants were in good

health. The questionnaire covered several areas including personal factors (name, gender, age,

etc.), years of living in their current cities and personnel environmental control.

The questionnaire also included the traditional scales of thermal sensation and thermal

preferences, current clothing garment and metabolic activity. The thermal sensation scale was

the ASHRAE seven point scale ranging from cold (-3) to hot (3) with neutral (0) in the

middle. The three point thermal preference scale asked whether the respondents would like to

change their present thermal environment. Possible responses were “want warmer”, “no

change”, or “want cooler”. Clothing garment check list were compiled from the extensive lists

published in ASHRAE -55, 2004. Metabolic rates were assessed by a check of activities

databases published in ASHRAE-55, 2004. The summary of the background characteristics of

the subjects are presented

Table 1 Summary of the Sample of Residents and Personal Thermal Variables

Sample Size 220

Mean 33.2

Age (year) Maximum 23 years

Minimum 5 months

Metabolic rate Clothing

insulation 75(W/m

2)

1.5 Clo

3.3. Data Collection

Both physical and subjective questionnaires were obtained simultaneously in the visit of the

field survey. This study investigates thermal environment and comfort of office buildings in

the Karunya University. A total of 220 subjects in naturally ventilated 11 office buildings (

with occupant – operable windows) provided 220 sets of cross-sectional thermal comfort data,

first field campaign from Mar 15, 2010 to Mar24,2010 and second field campaign from

Sep10,2010 to Sep 19, 2010 in Karunya University, Coimbatore. In both the set of data

collections the same buildings were taken into account for data collection. Indoor climatic

data were collected using instruments, with accuracies and response times in accordance the

recommendations of ANSI/ASHRAE 55. All the measurements were carried out between

10:00 hours and 16:00 hours.

A number of instruments were used to measure the thermal environment conditions, while

the respondents filled in the subjective thermal comfort questionnaire. The instruments were

standard thermometer for air temperature, whirling hygrometer for humidity, globe

thermometer for radiant heat, kata thermometer for air velocity. Metabolic rate can be

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S. Elizabeth Amudhini Stephen

http://www.iaeme.com/IJCIET/index.asp 368 [email protected]

estimated using standard Table found in ISO 7730. Among the residential respondents, air

temperature readings were taken at a minimum of two locations in each space and at two

different levels corresponding to the body level and the ankle level corresponding to

approximately 0.1 m and 1.2 m above the floor level, respectively. Instruments used in this

study met the ASHRAE standards‟ requirements for accuracy.

During the survey period, there were no significant sources of radiant heat in residents‟

apartments. Therefore the operative temperature is close to the air temperature. The insulation

of clothing ensembles was determined using the Olsen‟s 1985 summation formula:

Icl= ∑ I clu,i where Icl is the insulation of the entire ensemble and I clu,i represents the

effective insulation of the garment i. The garments values published in the ANSI/ASHRAE

Stand card 55-2004 was the basis for the estimation of clothing ensemble insulation. The

general mean clothing-insulation value of 1.5 clo was recorded among all the respondents.

The majority of the respondents were seated on partly or fully upholstered chairs at the time

of survey. This appears to have been reflected in the generally higher mean value of 1.1 clo

recorded among the subjects at home.

The metabolic rates were determined from the activities filled by the subjects and as

observed at the time of the survey. Uniform value of 75 W/m2 was assumed for respondents

of the residential buildings. This assumption is based on the ISO 7730 Table of metabolic

rates for provisions for relaxed seating which was assumed to be the case with all subjects in

their homes.

3.4. Subjective Questionnaire

The subjective questionnaire consists of the following areas. All the surveys are “right now”

surveys. It takes 15 minutes in average for a participant to answer those questions.

Table 2 Range of values

Fcl Ta Tmrt Vair Pa Tcl M(met) Icl(clo)

Min 0 16 19.5 0.1 0.01 27 75 1.5

Max 1.5 34 23 1 1 29 75 1.5

Therefore the Problem is to minimize PMV for office

( ) *( ) , ( ) - ,( ) - ( ) ( )

,( ) ( )

- ( )+

( ) ,

,( ) ( )

- ( )-

{ ( )

( ) √

√ ( ) √

}

Subject to the following constraints (bounds)

0 ≤ Fcl ≤ 1.5;

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Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques

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16 ≤ Ta ≤ 34 ;

19.5 ≤ Tmrt ≤ 23;

0.1 ≤ Vair ≤ 1;

0.01 ≤ Pa ≤ 1;

27 ≤ Tcl ≤ 29;

M = 75;

Icl = 1.

4. ALGORITHMS

4.1. Genetic Algorithm

4.1.1. Options Set for the Algorithm

Initial population: 20.

Elite count: 2.

Cross over fraction as 0.8.

Max Time Limit: ∞.

Max Generations: 100.

Fitness Limit: -∞.

Selection: Stochastic.

4.1.2. Stopping Criteria:

If the maximum generations is reached (100).

If maximum time is reached (∞).

If average change in function value < 10¯⁶.

4.2. Simulated Annealing

4.2.1. Options Set

Initial Temperature: 100.

Annealing Function: Fast Annealing.

Reannealing interval: 100.

Time Limit: ∞.

Max.function evaluation: 3000 No. of variables.

Max. Iterations: ∞.

Function Tolerance: 10¯⁶.

Objective Limit: 10¯⁶

4.2.2. Stopping Criteria

Max. Time reached.

The average change in value of the objective function is < 10¯⁶.

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S. Elizabeth Amudhini Stephen

http://www.iaeme.com/IJCIET/index.asp 370 [email protected]

Max. Iterations are reached.

If the number of function evaluations reached.

If the best objective function value is less than or equal to the value of Objective limit it is

stopped.

4.3. Pattern Search

4.3.1. Options Set

Poll Method: GPS positive Basis 2N.

Initial Mesh size: 1.

Expansion Factor: 2.

Contraction Factor: 0.5.

Mesh Tolerance: 10¯⁶.

Max. Iteration: 100 No. of Variables.

Max. Function Evaluation: 2000 No. of Variables.

Max. Time Limit: ∞.

Function Tolerance: 10¯⁶

4.3.2. Stopping Criteria

Mesh Tolerance: 10¯⁶.

Max. Iteration: 100 No. of Variables.

Max. Function Evaluation: 2000 No. of Variables.

Max. Time Limit: Inf.

Function Tolerance: 10¯⁶

4.4. Particle Swarm Optimization

4.4.1. Options Set

Max.Generation = 200.

Max. Time Limit= ∞.

Average change in fitness value= 10-6

.

Time Limit = ∞.

Function Tolerance= 10-6.

Cognitive Attraction = 0.5.

Population Size = 40.

Social Attraction = 1.25.

4.4.2. Stopping Criteria

Max.Generation = 200.

Max. Time Limit= ∞.

Average change in fitness value= 10-6

Time Limit = ∞.

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Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques

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Function Tolerance= 10-6

4.5. GODLIKE

4.5.1. Options Set & Stopping Criteria

Max.FunEvals = 10-5

.

Max. Iterations = 20.

Min. Iterations = 2.

Total. Iterations = 15.

Function Tolerance = 10-4

4.6. Fmincon

4.6.1. Options Set for ‘Fmincon’

Max.Iterations:400.

Max.function Evaluations: 100 No. of Variables.

Max.Time:∞.

Max. Function Tolerance: 10-6

.

4.6.2. Stopping Criteria for Global Search

Max.Time: Inf.

Max Wait cycle: 20

4.6.3.Stopping Criteria for Fmincon

Max.Iterations > 400.

Function Tolerance: 10-6

4.7. Direct Evolution

4.7.1. Options Set

Min. Value to Reach = 10-6

.

Population Size = 10 D.

Max. Iterations = 200.

Step Size F = 0.8.

Cross Over Probability = 0.5.

Strategy= 7 (DE/rand/1/bin)

DE/x/y/z, where DE stands for DE, x represents a string denoting the vector to be

perturbed, y is the number of difference vectors considered for perturbation of x, and z stands

for the type of crossover being used (exp: exponential; bin: binomial).

4.7.2. Stopping Criteria

Max.Value of function reached= 10-6

.

Max.Iterations=200

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S. Elizabeth Amudhini Stephen

http://www.iaeme.com/IJCIET/index.asp 372 [email protected]

4.8. LGO

4.8.1. Stopping Criteria

If the current best solution did not improve for

Program execution time limits > 600 seconds.

4.8.2. Local Search Termination Criterion Parameter

first local search phase ends, if the function difference is less than

If max. constrain violation exceeds

4.9. glcCluster

4.9.1. Stopping Criteria

Maximum Iterations = 10000;

Maximum Function count = 10000;

Tolerance of Variables = 10-5

Function Tolerance =10-7

4.10. glcSolve

4.10.1. Stopping Criteria

Max.Iterations is exceeded > No. of variables 1000.

Max.function evaluations > No. of variables 2000.

If the difference of objective function is < 10-6

5. COMPARISON TABLE

Table 3 Comparative results of optimization methods for office thermal comfort.

PMV PPD -OFFICE

Methods Fcl Ta Tmrt Vair Pa Tcl PMV PPD TIME ITERS

GA 0.701 21.097 20.734 0.5073 0.2702 28.118 -0.5 5 0.53906 51

SA 0.710 20.647 21.367 0.5418 0.5946 28.231 -0.5 5 4.103220 3001

PS 0.75 25 19.545 1 0.255 28 -0.5 5 0.397420 26

PSO 0.80697 22.19925 21.58457 0.54836 0.47377 27.85813 -0.5 5 0.0954566 51

Godlike 0.84890 22.66393 20.96814 0.44038 0.555895 28.04283 -0.5 5 3.0026599 4

Fmincon 0.86431 23.18258 21.26676 0.555685 0.53481 28.22689 -0.5 5 14.68332 2288

DE optimization

SOLUTION

0.88907 23.46064 21.36051 0.664525 0.44529 28.20742 0.368 5 0.55702425 12000

LGO 1.2668 25.8503 20.8447 0.1 0.2887 28.5338 -0.5 5 1.0661718 3883

glcCluster 0.76 24.9946 21.4981 0.852 0.3922 28.6711 -0.5 5 0.6147302 1532

glcSolve 0.75 19 22.83333 0.25 0.0528 27.3333 -0.5 5 0.79695503 1771

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Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques

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-5

0

5

10

15

20

25

30

35

Fcl Ta Tmrt Vair Pa Tcl PMV PPD TIME

GENETIC ALGORITHM

SIMULATED ANNEALING

PATTERN SEARCH

PSO

GODLIKE

NON LINEAR

NUMERICAL optimizaion SOLUTION

LGO

glcCluster

glcSolve

Analytical

Figure 1 Comparative graph for office thermal comfort

The PMV and PPD have the same value as -0.5 and 5 for all the ten optimization

techniques except for DE, which has 0.36 as PMV. The elapsed time is maximum for fmincon

and minimum for PSO and PS. All the other parameter values are more or less the same for

all the ten optimization techniques. Now, the parameter values are taken separately and the

ten optimization techniques need to be compared so as to find which method is the best

method of optimization.

Table 4 Comparative Table for parameters in all 10 methods

Variable GA SA PS PSO GL Fmincon DE LGO Glc

Cluster

Glc

Solve Fcl X X 0.75

X X X X 1.26

0.76

0.75 Ta X X

25 X X X

25.8

24.9 19 Tmrt X X

19.54 X X X

20.84

21.49

22.83 Vair X X 1

X X X 0.1

0.852

0.25 Pa √

0.255

0.28

0.39

0.05 Tcl X X 28

X X X 28.533

28.67

27.33 PMV

-0.5

-0.5

-0.5

-0.5

-0.5

-0.5

-0.5

-0.5

-0.5

-0.5 PPD 5

5

5

5

5

5

5

5

5

5 Time 0.39 0.095

Iters X X 26 4 X X X X X

6. RESULT AND DISCUSSION

With the two extreme values of parameters from survey, the optimization is carried out with

different solvers. As they are of the stochastic type, their results may vary from trial to trial

and the problem is made to run for 20 trials (Elbeltagi, Tarek Hegazy, & & Grierson, 2005)

and an average of all trials is taken as the final value of the parameter, by the solver. The

solvers are compared with three different criteria.

6.1. Consistency

The consistency Table gives the parameters that remain constant for all the trials. All the

solvers give the same value of PMV& PPD for all the runs except DE, which in turn indicate

that the comfort requirements are in the acceptable range.

Fcl - P.S & glcSolve (0.75), glcCluster (0.76), LGO (1.26)

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Ta - P.S (25), glcSolve (19), glcCluster (24.9), LGO (25.8)

Tmrt - P.S (19.54), glcSolve (22.83), glcCluster (21.49), LGO (20.84)

Vair - P.S (1), glcSolve (0.25), glcCluster (0.852), LGO (0.1)

Pa - P.S (0.255), glcSolve (0.05), glcCluster (0.39), LGO (0.28)

Tcl - P.S (28), glcSolve (27.33), glcCluster (28.67), LGO (28.53)

So we see that the solvers Pattern Search, glcSolve, glcCluster& LGO remain constant

throughout their runs.

Minimum Run Time

For a minimum run time of the problem, we got PSO (0.095 seconds), Pattern Search

(0.39 seconds).

Minimum Evaluation

This criterion will determine the effectiveness of the algorithm. From the result table, we

see that the Pattern Search and GODLIKE algorithms have minimum evaluation of 26 and 4

respectively.

Simplicity of Algorithm

Of all the algorithms we have taken, the Pattern Search algorithm is the most simplest

followed by GA, PSO, DE, Simulated Annealing, GODLIKE, Non-Linear, Direct algorithm.

Results according to Standards

This is the most important criterion that determines whether the solver is practical or not.

We got the standard values for a naturally ventilated building from ASHRAE as:

Humidity: 30% to 60%

(http://www.epa.gov/iaq/largebldgs/i-beam/text/hvac.html)

This gives that the Pa should lie within the range of:0.0765 to 0.501

Operative Temperature: 17.75 to 28.5

Air velocity:0.2 to 0.8 ms-1

(1 ms-1

only at extreme conditions)

With the above standards the solvers which adhere to the standard are:

Air-Velocity: Fmincon, GA, SA, PSO, GL, DE, glcSolve.

Partial vapour pressure: GA, PS, PSO, DE, LGO, glcCluster, glcSolve

Operative temperature: GA, SA,PS, PSO, Fmincon, DE, GL, LGO, glcCluster, glcSolve

The following Table gives a summary of all the criteria for the solvers:

Table 5 Summary of all the criteria for the solvers

Criteria GA SA PS PSO Fmincon DE GL LGO glcClus glcSolve

Result according to

ASHRAE

3/3

=100%

2/3

=67%

2/3

=67%

3/3

=100%

2/3

=67%

3/3

=100%

2/3

=67%

2/3

=67%

2/3

=67%

3/3

=100%

Consistency - - - - - -

Min-Run Time - - - - - - - -

Min-Evaluation - - - - - - - -

Simple Algorithm - - - - - - - - -

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Optimization of Thermal Comfort in Office Buildings Using Non-Traditional Optimization Techniques

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Thus it is seen that the Pattern Search solver satisfies all the criteria and scores 67% for its

practicality in giving result according to ASHRAE. So the appropriate algorithm, for

optimization of thermal comfort is suggested as Direct search algorithm & the solver is

PATTERN SEARCH

7. CONCLUSIONS

This study investigates thermal environment and comfort of office buildings in the Karunya

University. A total of 220 subjects in naturally ventilated 8 office buildings ( with occupant

– operable windows) provided 220 sets of cross-sectional thermal comfort data, first field

campaign from Mar 15, 2010 to Mar24,2010 and second field campaign from Sep10,2010 to

Sep 19, 2010 in Karunya University, Coimbatore. In both the set, the same buildings were

taken into account for data collection. Indoor climatic data were collected, using instruments

with accuracies with the recommendations of ANSI/ASHRAE 55. All the measurements were

carried out between 10:00 hours and 16:00 hours.

In the experiment conducted using ten non-traditional optimization techniques, the

thermal sensation takes the value -0.5, which is in the acceptable range , where the acceptable

range is -0.5 to +0.5 (ANSI/ASHRAE55-2004, 2004). From the thermal comfort value, we

can conclude that the thermal comfort of the office buildings of the Karunya University is in

the acceptable range and hence the thermal comfort in this area is optimum.

Here, ten non-traditional optimization algorithms were presented. These include: GA, SA,

PS, PSO, GL, FMINCON, EA, LGO, glcCluster, glcSolve. A brief description of each

method is presented along with a Pseudo code to facilitate their implementation. MATLAB

programs were written to implement each algorithm. The thermal comfort problem for the

offices of the Karunya University was solved using all algorithms, and the comparative results

were presented.

REFERENCES

[1] ANSI/ASHRAE55-2004. (2004). Thermal Environmental conditions for Human

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