Gasoline Combustion

For gasoline or any other fuel to burn properly, it must be mixed with the right amount of air. The mixture must then be compressed and ignited. The resulting combustion produces heat, expansion of gases, and pressure. The pressure pushes down on the piston to turn the crankshaft.

Normal gasoline combustion

Normal gasoline combustion occurs when the spark plug ignites the fuel and burning progresses smoothly through the fuel mixture. Maximum cylinder pressure should be produced a few degrees of crank rotation after piston TDC on the power stroke.

A spark at the spark plug starts the fuel burning. A small ball of flame forms around the tip of the plug. The piston is moving up in the cylinder, compressing the fuel mixture.

The flame spreads faster and moves about halfway through the mixture. Generally, the flame is moving evenly through the fuel mixture. The piston is nearing TDC, causing increased pressure.

The piston reaches TDC, the flame picks up mores speed.

The flame shoots out to consume the rest of the fuel in the chamber. Combustion is completely with the piston only a short distance down in the cylinder.

Normal combustion only takes about 3/1000 of a second. This is much slower down in the cylinder. Dynamite explode in about 1/50,000 of a second.

Under some undesirable conditions, however, gasoline can be made burn too quickly, making part of combustion like an explosion.

Inspecting injection system

A general inspection of the engine and related components will sometimes locate gasoline injection troubles. Check the condition of all hoses, wires, and other parts. Look for the fuel leaks, vacuum leaks, kinked lines, loose electrical connections, and other troubles. Spend more time checking the components most likely to cause the particular symptoms.

Verify the problem

Before you test the system, verify the problem or complaint. Make sure that the customer or service writer has accurately described the symptoms.

Never repair a gasoline injection system until after you have checked all possible problem sources. The ignition system, for example, normally causes more problems than an injection system.

Gregory D. Lorson

https://gregorydlorson20.wordpress.com/2012/03/07/gasoline-combustion/

ANCIENT INDUSTRIES AND TRADE ROUTES

In early times the Near East became a center of industrial and mercantile activity as well as of agricultural production. The peasant cultivators supplied the manufacturing and trading cities with food; the skilled craftsmen made products for markets near and far. Commerce developed at first along the river highways and then on the caravan and sea routes to more distant lands. The cities of the Near East became the foci of trade routes reaching far into Europe, Asia and Africa. North and south, east and west, merchandise was carried along the rivers, across the deserts and steppes, and over the seas. Through central Asia ran the great caravan routes to China. By way of the Aegean, the Straits (the Dardanelles, the Marmora Sea, and the Bosporus), and the Black Sea men found easy water passage to the rivers of Eastern Europe, which gave access to the great Eurasian plain stretching from the Urals to the Vosges Mountains. The Red Sea and the Persian Gulf furnished high ways to East Africa and to India. The Mediterranean made trade possible with North Africa and southwestern Europe. Active local caravan routes which traversed Anatolia, Syria, Palestine and Arabia provided connecting links in theirs intercontinental transportation system. For many centuries the near east, as a nexus of trade routes, enjoyed a most favorable geographical position for economic prosperity. Connected with these geographic features, which contributed so greatly to the welfare and cultural progress of the Near East, were certain disadvantages. The caravan and sea routes became avenues of invasion accessible to the Indo-European nomads from the north and to the Turkish and Mongolian nomads from the east. The caravan routes crossed arid and semiarid lands suitable only for wandering tribes, who were ever a threat to the trade routes and the agrarian and urban population. The great wealth of the Near Eastern cities was constant temptation to invasion by “barbarian” nomads, as well as by predatory civilized states.

 

Gregory D. Lorson

https://gregorydlorson20.wordpress.com/