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A view from the ‘crow’s nest’



A long watch: War Captivity and Return in Sri Lanka

Reviewed by Ransiri Menike Silva

I have just been released, for the second time from the grip of ‘A Long Watch’ after an interval of about two years, and found it as arresting as before but this time with an added awareness and sensitivity that had eluded me the first time. Authentic accounts of escapee prisoners of war (POW’s) had always interested me, irrespective of the era or the nationality. But this was different. It was OUR story revealed by a senior ranking Naval officer who had been captured by the LTTE and held prisoner for eight years.

My first introduction to it took place some years ago. I was visiting my brother, a retired Naval officer, to find him in animated conversation with a lady visitor. At the end of her stay, she left behind some papers which my brother waved at me saying that it was the manuscript of a book being compiled for publication about the Naval officer Ajith Boyagoda who had been a prisoner of the LTTE for eight years. As my brother was also a well-known writer, she had requested his comments. This was Sunila Galappatti who had interviewed Boyagoda.

I was excited at the thought of reading it when it was published, but it reached the public only a long while later. I grabbed several copies of it, when at a leading bookshop I found it leaning contentedly against my own book, ‘The Blue Door’, on a crowded shelf.

It is a well compiled book with short informative chapters whenever possible, which gives the impression that the narrator is speaking to you direct and not through a third party. For this novelty in presentation, Sunila Galappatti has to be congratulated and applauded for it is she who listened to his story, gently drawing out lurking details, some extremely painful, to set them in a proper sequence that could be absorbed in its entirety without a break. An onerous task performed with dedication that reveals Sunila’s versatile literary skills.

The narrative leads gradually up from his youth to the point of his capture by the enemy, along with a few others and not by himself. This fact has been deliberately omitted from the twisted, falsified versions touted in order to (wrongfully) convince the public that he went over willingly. It is ironic that this same little group of captives were together during their incarceration and released almost together, thereby forming a bond that has continued to this day through direct contact with one another whenever possible.

From the point of his capture, the story undergoes a change of mood. The overnight change in their status, from free men to captives, causes a subtle alteration in the character of individuals, each affected in a different way.

The fluctuations in their daily routine caused by the sudden unpredictable moves indulged in by their captors, is an added obstacle to any form of acceptance of their situation. These involved being shepherded into trucks, sometimes blind-folded, and driven in the night for long hours through unknown territory to be deposited in yet another camp. Hearing a familiar bark in two different locations convinced Boyagoda that the journey taken through a long circuitous route was a ruse to give the prisoners the impression that it was a long distance away and not the short direct one it really was.

Surreptitiously exchanging facts about the LTTE among themselves, the Sinhala prisoners became aware of the fact that some of their fellow captives were themselves unwilling slaves of the LTTE movement. Arrested on fake charges these civilians were inducted into their labour force which had many gaping vacancies. (Shades of the South!)

The majority of people, in both the North and the South, are ignorant about the origins of the LTTE movement, which was a fight against the caste system practiced by the Hindus, which debarred low caste people from entering a Kovil even for religious worship.

Velupillai Prabhakaran belonged to a low caste, and began to realize the unfairness of it and the implications it had on the majority of the citizens, on reaching adolescence. Exposure to Christianity where all men are considered equal had him converting to that faith.

After that, his eye focused on one target; the annihilation of all High Caste Hindus. Gathering a band of like-minded youth around him they created as much destruction as they could.

At this time, across the seas in Tamil Nadu a secret movement had been formed with the aim of creating a Tamil Homeland, with Jaffna as their chosen site.

Hearing of Prabhakaran’s activities they decided to use him as their cat’s paw. Taking him and his supporters to Tamil Nadu they indoctrinated them with their ideas while also giving them military training, thereby subtly moulding them into the shape required. They were brought back to Jaffna with the main target of a Tamil Homeland implanted firmly in their immature brains, the original anti-caste goal pushed to the sidelines.

Prabhakaran was instigated into assassinating Alfred Duraiappah after which he was rowed away to a haven in Tamil Nadu. Many years later he returned as an adult, with an over inflated ego and besotted by an insatiable greed for power. He even distanced himself from his own family who refused to be converted to his new way of thinking, his father remaining a loyal clerk in the Jaffna Kachcheri, who had served under my brother when he was the Government Agent there.

His activities attracted western powers who considered him the perfect tool for the manipulation of their own hidden interests and so stepped in the USA, the UK, Norway and others assisted by Anton Balasingham who had acquired a ‘white’ wife through dubious means. It was only after Jaffna was over-run completely by the Government Forces that it revealed to what horrendous extent they had assisted.

An entire city had been created underground with housing, car parks, offices, residential areas and a highly advanced fully equipped hospital with vital drugs and qualified medical staff.

Air power was assured with ground to air missiles, air planes, trained pilots and a proper airstrip that our own helicopter pilots had spied from above.

The Sea Tigers had their diving and other underwater training at a vast swimming pool. A special, secluded heavily guarded area was also set aside for King Prabhakaran to indulge in jogging and other health enhancing activities. My family and I saw these as ‘tourists’ soon after the destruction of the LTTE and before they were rightfully reduced to rubble by our Army.

All these developments had taken place with the full knowledge of succeeding governments in power at the time which had had underhand dealings with the enemy under the guise of ‘Peace Pact’, ‘Peace Accord’ and other such fanciful labels. The LTTE was also rewarded substantially when at the request of the President in power at the time, they eliminated those whom he believed were a threat to his position of TOP DOG in the country.

The lower ranks were not spared either, with 600 young policemen being offered on a golden platter to Prabhakaran.

“Into the Valley of Death

Rode the six hundred”

It was Boyagoda’s misfortune to be a participant in a disturbing situation when a highly placed ‘officer’ of the LTTE patted jeeps and other valuable equipment and declared sarcastically “Gifts from Premadasa.” That was the infamous era of the ‘Premadasa Yugaya’ which is now being glorified by his son who is threatening to inflict upon us the same once again.

Boyagoda’s captors and fellow prisoners comprised a collection of ‘the good, the bad and the ugly’, which gave birth to an intimacy in relationship between individuals irrespective of age or position in life, though an unexpected hurdle was encountered in the incompatibility between the generations. The detailed descriptions of the terrible tortures they had to endure is searing as some are inhumanly savage. Yet this is nothing new to us who are aware of the interrogating tactics of Police Forces everywhere. Although they themselves were not too brutally tortured physically, occasional muffled screams would reach them from some unlocatable source convincing them that hidden torture chambers existed elsewhere.

Their apparent journey through a dark unending tunnel despaired them until a faint glimmer at the far end appeared with the involvement of the ICRC. That was when Boyagoda had a new status thrust upon him, that of ‘SHOW’ prisoner. As public eye-wash he was ordered to have a proper bath (a luxury!) then spruced up in new attire and given a good feed before being displayed to groups of media men, university students, merchants and other curious folk, with cameramen working overtime.

After each such exhibition he was whisked away, divested of the false costume and dropped back in the same cesspit he had wallowed in, prior to the charade, in which he had been an enforced actor.

Being the highest ranking officer of the government forces they held on a leash, he became the LTTE’s chief bargaining tool. This transparent ruse did not fool the ICRC which was an independent institution and tolerated no spies in disguise at their meetings with the prisoners thereby enabling Boyagoda to speak freely. He revealed the terrible conditions under which they were forced to exist – not live, and appealed for help. Positive results followed. Their next visit saw them loaded with ‘goodies’ for the prisoners; books, magazines, outdated newspapers, letters from their families, clothes, extra nourishment, medicines etc.

By this time Boyagoda had undergone a significant change. His eye-sight and hearing had deteriorated badly along with his mental faculties. He was weak, almost a walking skeleton and physically inactive. Announcing their discovery to the outside world the ICRC invited assistance from whoever was interested in helping them. It was then that Boyagoda began receiving monthly issues of Newsweek and National Geographic Magazines which Vijitha Yapa had gifted as a two year subscription in Boyagoda’s name. Thank you Yapa for that act of unreserved generosity, a true Dana in the Buddhist sense.

Later the ICRC also succeeded in arranging meetings between the prisoners and their immediate families, which carried with it the faint possibility of release through an exchange of prisoners. This did not affect Boyagoda, who was fully aware of his unchanging position – that of main bargaining tool of the LTTE. Finally, after eight long excruciating years in captivity he was chosen for release, but ironically not as a personal reward but in exchange fora very important LTTE member they wished to have back.

Now another phase of Boyagoda’s life begins. His transition from captive to free man is as excruciatingly painful as the ordeal he had endured in reverse order eight years earlier.

He was unable to adapt himself to ‘normal’ life either socially or domestically. He did not belong anywhere and was a stranger even in his own home. At first, he would walk around the house searching for a member of the household to obtain permission to use the toilet. The poignancy of this impacted most forcefully on me, being almost moved to tears by the deep sadness it generated.

His professional life was equally devastating. The Navy he rightfully belonged to, did not want him, as his presence was an embarrassment to them. They were keen on ridding themselves of him whom they believed to be a traitor. Much had changed in the period between his capture and his release. There had been an escalation in violence which affected the priorities in duty and performance. An added ordeal was the mid-ocean smuggling of drugs and other dangerous things which forced them to be extra vigilant. Had there been informers? Perhaps, but they would never be able to identify them. Personnel death rate was high.

So they mistrusted anything that had even a brush-stroke of the enemy daubed on them. They could not afford to be negligent. Such situations are inevitable in a state of war and have to be accepted.

When he was released he was sick; malnourished and weak with an unsettled mind. But instead of giving him the vital care he needed, he was treated like a flea infested mongrel. Even some wives of Navy personnel whom I know, were firmly convinced that Boyagoga had gone across to the enemy willingly, with the LTTE according him a high position and also financially supporting his family in his absence. Seeped in self-righteous misconceptions they shunned the devastated family of their colleague who were treated like lepers. Learning of this shocking behavior on the part of people I knew, I lost all regard for them. To such pitiable people, I have only this to say, remember the words of Jesus Christ – “Let him who has not sinned cast the first stone.” But on reflection I have the feeling that these bigoted buffoons may even refuse to acknowledge the existence of Jesus Christ!

The same clique of Navy personnel who were captured along with and shared their period of incarceration together with Boyagoda were released about the same time as he. The Navy welcomed them back in to the service where they ran into one another at Naval Head Quarters, and still keep in touch after retirement.

Now here is an interesting conjecture. Many, including the Navy had vehemently denied the existence of these people, so how come they suddenly manifest themselves in human form now? I suppose one has to trek to the Himalayas to get a solution from the hermit ascetics there!

The excellent training given to its cadets by the Navy was proved by the ‘Old Guard’, Boyagoda’s colleagues and friends who stood loyally by him as they had done with his family throughout his incarceration. Treated like something ‘the cat brought in’ he would on occasion be hauled out of obscurity whenever it suited various groups of people, mainly the politically motivated ones. Suddenly he would find himself hauled up to the main stage sharing it with prominent personalities. A (comic) repetition of his former role of ‘SHOW PRISONER’!

The personal revelations and reflections recorded in the book was an eye-opener for me. My attitude to life was changed by the over-all view I had gathered, even though I had myself weathered many a storm in my own life.

This is not only a ‘must read’ book but also one to be ‘re-read’ many times over. It should also be shared, lent, gifted, passed around and talked about at every turn. I am grateful to the great duo; Commodore Ajith Boyagoda and Sunila Galappatti for gifting us this panorama of life, the over-all view one gets from the ‘Crow’s Nest’ of a ship.

And now to end this on a hilarious note. Those of our vintage will remember the infamous IPKF (Indian Peace Keeping Force) deal, with its ‘Parippu Drop’, struck between our President, J.R. Jayawardena and the Indian Prime Minister, Rajiv Gandhi. The entire country was against it, even inciting schoolboys to parade the streets in protest. At a ceremonial parade for the visiting dignitary, a young Naval rating had suddenly raised his rifle and brought it down in an attempt to hit Rajiv Gandhi and failed. Years later, this boy had confessed to his senior officers that he still regretted missing his target that day, which had been J.R. and not Rajiv!

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An air of discontent prevails



We have had a series of “Avurudhu parties” here in Aotearoa. No shortage of Kavum, Kokis, Athiraha, and even Wali Thalapa. Buffalo curd available locally and of course imported treacle in abundance. Yours truly has assumed the role of a fly on the wall during these festivities and gleaned much information, worth talking about.

First to get on to the Pearl, the talk of the botched-up vaccination plan and running out of the second dose of vaccine. Bizarre permutations as to what would happen if the second dose was not available on time and to who would be press-ganged into getting the “dodgier” types of vaccine from China and Russia, etc. The possible repercussions of getting a second dose of another type of vaccine to the original, the speculations of which left me rather glad that the general populace of Aotearoa has not been vaccinated to date. The talk moved on to the Easter bombings and the recent comments by leaders of the Roman Catholic church as to the possible perpetrators of the attack. Some increasingly obvious conclusions as to those responsible for the planning and funding of same are being reached by those other than some of us who dared to voice our opinions over a year ago! This combined with the increasing and very rapid unpopularity of the person they elected to high office hoping he was genie of the magic lamp type, and the possible reverse of Hong Kong that could take shape on the reclaimed land near the Colombo port, does not bode well for an already dubious future. By reverse of Hong Kong, I mean Hong Kong is trying to hold out as a bastion for democracy, whilst the proposed port city seems to be modeled on the opposite!

Moving on to Aotearoa, the rest of the world seems to be praying for a leader such as our own Jacinda Ardern, but the fat cats of Aotearoa are getting rather sick of her. Those who own multiple houses and have been setting off their interest payments against their taxes due to a loophole in the law that has now been plugged are grumbling. The fact that most young people can’t afford to buy their first houses due to rich people and property developers snapping up all available property, happily funded by banks who are only interested in the bottom line, is of no consequence to them. The fact that this could lead to so much discontent that it could even lead to armed insurrection doesn’t bother them. They seem to have forgotten that we have had almost no deaths and hardly any Covid 19 cases in our community when they say that the lockdowns, we underwent were too excessive and how the economy and business sector has suffered. These very people throng the stadia during the rugby and cricket games and enjoy music concerts with gay abandon. Megacorporations are not happy about the restrictions that are coming on with regard to the use of Liquid Petroleum Gas (LPG) due to environmental concerns. To top it all off I had a lecture from my 13-year-old daughter about how I am being “led by the nose” by Jacinda Ardern and her propaganda! Where she got that from could only be from her elder brothers whose get rich quick schemes have seen a setback due to certain leftist policies coming in from the Labour government that is in power with an absolute majority.

I laugh to myself and think about other examples I have seen of self-proclaimed pundits never being content with their lot. My education was in a very large Government school. As a perfect and a member of some sports teams we handled the administration and some of the governance of this school. Later in life when my children were attending a private school I got involved in the Executive committee of the PTA of that school. The “problems” faced by the private school and the vast dramas that were involved in trying to solve those problems were laughable when compared to those faced by even us, senior students (a much lower level in the administration) of the Government school.

It led me to believe that people always grumble. They are never content with their lot and there is always someone plugging their case and trying to sow the seeds of discontent among the populace. If those living in Aotearoa, in the present situation and well aware of the chaos and mayhem that is prevailing in the rest of the world are dissatisfied, when will anyone be satisfied? Everything is relative and one should try to step outside the confines of one’s own situation and look at the broad picture. In the words of learned barristers, I rest my case!

This week’s missive will not be complete without a tribute to the memory of Prince Phillip, the Duke of Edinburgh. He lived through some of the best and worst times of human existence on this planet and conducted himself impeccably. He showed his humanity and his failings, with a few bloopers down the line but most of those had an undercurrent of humor and couldn’t really be construed as offensive, despite the best efforts of the media and others to make them so. He served as consort to her Majesty the Queen with loyalty and aplomb and he leaves behind an enviable legacy in the world of conservation and youth affairs. It is hoped that his heirs will be up to the task for they face a task which in cricketing terms could be classed as coming into bat after the great Sir Vivian Richards had just scored a century, in his prime. Something very difficult to surpass in skill and entertainment value. Unfortunately, the Duke made just 99. May he rest in peace!


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We have much to learn; and emulation is no disgrace



“Imitation is the sincerest form of flattery that mediocrity can pay to greatness.” said Oscar Wilde who, through sharply ironic wit, often proclaimed the absolute truth.

Cassandra quotes him today as she wants to point out how much we in Sri Lanka can benefit by reaping some ideas from the recent royal funeral in Windsor. And she does not excuse herself for placing stress on our mediocrity as juxtaposed with greatness. Nationalists may shout themselves hoarse and bring down a few more majestic trees by decrying the comparison. They can justifiably claim we have a cultural heritage of two and a half millennia but have we remained cultured, following faithfully and correctly the four great religions of the world? A loud NO from Cass, echoed by millions of others. Though Britain’s development of the English language, culture, arts and science was later than our civilization, they outstripped all countries at one time and are again elevated, while we are poised on bankruptcy, with the begging bowl in hand and thugs and thieves as legislators. We in Sri Lanka are mediocre if not degraded against the greatness shown by the Brits in many spheres. This is no Anglophile speaking but a dame who was born when the Brits were leaving us to govern ourselves and grew up with our statesmen doing a jolly good job of it; Sinhalese, Tamil, Burgher, and a few Muslims taking the lead graciously and effectively with complete honesty, to serve the people. They maintained and improved our country so it was admired by others and even some desiring to imitate Ceylon as Singapore’s Lee Kwan Yew admitted. And where are we now? Except the Rajapaksa family from Medamulana, wearing rose tinted glasses or with eyes shut by arrogance, and their followers and throngs of sycophants, others see our country and our people for what it, and the people, really are. No need to elaborate.


The funeral of Prince Philip juxtaposed against customs here

The low-key funeral observing all Covid-19 restrictions was noteworthy for being utterly devoid of bombast and vainglory. It was dignified and moving. Cass wonders how many of her readers watched the funeral on Saturday 17, late evening here. Prince Philip had detailed all arrangements from the Navy being prominent and other Forces joining in plus the substitution of the gun carriage with a jeep he had helped design. The horse carriage he was adept at racing was stationed close by the entrance to the chapel. He has bequeathed it to the daughter of his youngest son and Sophie; the Wessexes having been very close to him and the Queen.

The entire proceedings proved first and foremost that the royal family observed strict pandemic restrictions like mask wearing and physical distancing. There was no one rule for them and another rule for us, thus proving beyond doubt that England (usually), and more so the Royal Family (definitely) are a country and an institution despising double standards. The monarch decreed and abided by the same regulations that have restricted everyone else in the UK, sharing their fate. An anecdote is relevant here. The Queen learned that lesson long ago. She was 14 when her mother said, after Buckingham Palace was bombed in September 1940, that she “could look the East End in the face now.”

Do all our people follow rules common to everyone? Oh! My heavens NO! There are differentiations according to layers in society. Shangri La would host a party for a hundred when only 30 are allowed to gather. During the height of the first wave when restrictions were strict, SLPP electioneering saw hordes thrust together and baby carrying, patting heads and hand clasping mostly by Mahinda Rajapaksha sans a mask. He has a charismatic bond with the masses but that needed to be curbed. Sajith Premadasa’s meetings were strict on physical distancing and mask wearing.

Only 30 were invited to the extremely solemn and yes, beautiful funeral service at Windsor Chapel. This meant eliminating even close relatives of the Family; but it was done. The Queen sat distanced from her daughter and sons and their spouses. Her now diminutive figure seated alone emphasized the loneliness she must be feeling after a close and successful marriage of 73 years.

This brings to mind our First Ladies. Cass steps out bravely to say that Elina Jayewardene was a gracious lady of restraint and dignity, the only perfect consort so far. Cass remembers Hema Premadasa beating her breast (true) and crying over the coffin of her late husband’s remains – in the true sense of the word – at the Prez’s funeral at Independence Square. There is dignity in restraint of even tears over a death in public. Among the women Heads of the country, the mother completely beat the daughter in dignity and ability.

We Sri Lankan women are now much more restrained in our mourning at funerals. Time was when widows even hoarsely wailed their sorrow, coiled and roiled with grief, and begged the dear departed “To look once more; say one word.” Cass in all the expressed grief of such funerals suppressed her laughter with difficulty. How would it be if the corpse obliged?

The choir at the funeral of Prince Philip was just four – one woman and three men. But their singing resounded in the high vaulted, completely majestic, centuries old church. The lone kilted piper within the Chapel evoked much. The service itself was short, just a Reading, prayers and listing of the multitude of honours bestowed on the Duke of Edinburgh, whose medals and decorations were on display beside the alter. The Archbishop of Canterbury, Justin Welby, and the Dean of Windsor, David Conner conducted the service.

To conclude, the Duke of Edinburgh had advised and laid stipulations on a simple funeral with the necessary pomp and pageantry but low key and very unostentatious. The actual funeral was even more low-key with mourners requested not to be on the streets or place flowers. The latter they did in all the residencies of the Royal Family in appreciation of a man who faithfully stood by the Queen and in his own way gave service to the nation.

Coming back to Free Sri Lanka, we seem to stress on that first word Cass inserted to the country name, even in these dire times of no crowds. And the worst is milling crowds are apparently encouraged to boost popularity of certain VVIPs by sycophants and by the preference/orders of the VVIP himself.

Consider the funeral of Minister Thondaman: crowds in Colombo and all VIPs wishing to register their presence before the body, and then the commotion at the actual cremation Up Country. Consider this year’s Sinhala New Year celebrations which were very dignified at the President’s residence but were inclusive of all traditions and a large gathering in the PM’s home, even raban playing by the Second Lady, and milling crowds outside.


Roller coaster ride of the country continues

Cass is relieved she had a topic to write on; namely that we should emulate the manner in which the much admired Duke of Edinburgh’s funeral was conducted, abiding by his stricture of it being low key and the country’s Covid restrictions. Our leaders especially must accept the saying I quoted at the beginning.

The country continues its roller coaster bumpy ride with some crying out the country is being sold to the Chinese, we will be a colony of theirs after they occupy the Port City; and others in remote areas sitting down for days on end, some near 100 days, drawing attention to the human elephant conflict. Much is touted about the Bill relating to the rules to govern the Port City.

Cassandra listens to all, and is somewhat warned and frightened, but cannot comment. However, one matter she speaks about loud and clear. The people must be told the status quo of the pandemic – daily numbers catching the infection and numbers dying. This is not for interest sake or ghoulish appetites; but to know how things are so we relax a wee bit or shut in more stringently. The Covid-19 Task Force, or the Health High Ups (not Pavithra please) should tell the country of the true situ of the pandemic as it holds the country in its grip. We want to know whether the grip is tightening or weakening. Please give us daily statistics. This newspaper announces total numbers. No help. Are we expected to jot down figures, subtract, and give ourselves daily infection and death statistics? No! It goes to prove that other matters – political slanted, ego boosting and economics – are more important than warning, containing the pandemic, and saving lives.

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Do you pump Octane 95 Petrol to your car to get better performance?



If your answer is YES, this article is for you

Dr. Saliya Jayasekara.

Senior Lecturer Department of Mechanical Engineering
University of Moratuwa

Many passenger vehicles, including three-wheelers and motorcycles are fueled by octane 95 gasoline when octane 92 gasoline (petrol) is available at a lower price. 

Otto engine (petrol engine) is an internal combustion spark ignition engine invented by a German engineer Nicolaus Otto in 1876 and used in most of the light weight vehicles including cars, three wheelers and motor bicycles. Otto engines can burn most of the hydrocarbon fuels (including hydrogen and ethanol) that can mix with air by evaporation (low boiling point). But the combustion characteristics of different hydrocarbons are not the same when burned inside an engine. If an Otto engine is designed for a particular fuel, it would not perform similarly with a fuel that has a different chemical composition.

In a well-tuned Otto engine run on gasoline for which the engine is designed, the combustion of the gasoline (petrol) / air mixture will continue smoothly from the spark plug to the piston head by igniting successive layers of the mixture as shown in Figure 1 (a).

If low grade gasolines are used, the combustion of some of the air/ fuel mixture in the cylinder does not result from propagation of the flame front initiated by the spark plug, but one or more pockets of air/fuel mixture explode (Detonate) outside the envelope of the normal combustion front as shown in Figure 1 (b). This detonation can cause severe damage to the piston and the head of the engine while deteriorating thermal performance of the engine (low efficiency)

Gasoline is a petroleum-derived product comprising a mixture of different hydrocarbons ranging from 4 to 12 carbon atoms in a carbon chain with the boiling point ranging of 30–225°C. It is predominantly a mixture of paraffins, naphthenes, aromatics and olefins. Additives and blending agents are added to improve the performance and stability of gasoline. The engine designers learned that straight-chain paraffin have a much higher tendency to detonate than do branched-chain paraffin.

The tendency of a particular gasoline to detonate is expressed by its octane number (ON). Arbitrarily, tri-methyl-pentane, C8H18 (iso-octane) is assigned an ON of 100, while the straight-chain paraffin n-heptane, C7H16 is given an ON of zero. Hence, a fuel sample with the same anti-detonation quality as that of a mixture containing 90% iso-octane and 10% n-heptane is said to have an ON of 90. Gasoline is made up of a mixture of mostly branched-chain paraffin with suitable additives to give an ON in the range 90 –100. It was also learned through experiments that the ON of a gasoline blends (e.g. gasoline and ethanol) can be calculated by using weighted average ON of each compound. Most importantly, the octane number has nothing to do with the heating value (Calorific value) or the purity of the fuel.

Engine thermodynamics show that engines with a high compression ratio offer higher thermal performance than engines with a low compression ratio. These engines having high compression ratio require high octane gasoline (for example octane 95) to avoid detonation. However, using gasoline having higher octane ratings for the engines designed for a low octane rating (for example, 92 octane) would not provide an additional benefit or loss, other than increased fuel cost.

Therefore, it is important to know the designed octane number of the engine before fueling (refer owner’s manual of the vehicle). For example: the minimum ON requirement for two and three wheelers in south Asia is 87 (The World Bank). Most of the Toyota, Honda and Nissan models including hybrid engines recommend 92 octane gasoline.

Dr. Saliya Jayasekara received the B. Sc. degree in mechanical engineering from university of Moratuwa in 2001, and the M.Sc. and PhD degrees in decentralized power generation systems from Royal institute of technology Sweden and the Melbourne University Australia in 2004 and 2013 respectively. He has well over 13 years of national and international experience in design and installation of centralised/decentralised power plants, boilers (utility/package) and heat exchangers. Currently he is serving as a senior lecture at University of Moratuwa, a visiting lecturer and fellow at Deakin University Australia.

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