The quest for an engine which having the same or more power with higher fuel efficiency than the existing ones has started before many years. As a result of all these researches a new engine concept is formed, which is a six stroke engine. Lot of research works are conducting on this topic nowadays and already six types of six stroke engines were discovered yet. Of these the resent developed three six stroke engines, i.e., Beare head, Bruce crowers and Velozeta’s are undergoing tremendous research works.
During every cycle in a typical four stroke engine, piston moves up and down twice in the chamber, resulting in four total strokes and one of which is the power stroke that provides the torque to move the vehicle. But in a six stroke engine there are six strokes and out of these there are two power strokes. The automotive industry may soon be revolutionized by a new six-stroke design which adds a second power stroke, resulting in much more efficiency with less amount of pollution.
2. Symbols used
3. History of six stroke engines
4. Velozeta’s six stroke engine
2. Engine Parts Modified
4. Performance test results
4.4.1.Load test results
4.4.2.Pollution test results
The term six stroke engine describes two different approaches in the internal combustion engine, developed since the 1990s, to improve its efficiency and reduce emissions
In the first approach, the engine captures the waste heat from the four stroke Otto cycle or Diesel cycle and uses it to get an additional power and exhaust stroke of the piston in the same cylinder. Designs either use steam or air as the working fluid for the additional power stroke. As well as extracting power, the additional stroke cools the engine and removes the need for a cooling system making the engine lighter and giving 40% increased efficiency over the normal Otto or Diesel Cycle. The pistons in this six stroke engine go up and down six times for each injection of fuel. These six stroke engines have 2 power strokes: one by fuel, one by steam or air. The currently notable six stroke engine designs in this class are the Crower's six stroke engine, invented by Bruce Crower of the U.S.A; the Bajulaz engine by the Bajulaz S A company, of Switzerland; and the Velozeta’s Six-stroke engine built by the College of Engineering, at Trivandrum in India.
The second approach to the six stroke engine uses a second opposed piston in each cylinder which moves at half the cyclical rate of the main piston, thus giving six piston movements per cycle. Functionally, the second piston replaces the valve mechanism of a conventional engine and also it increases the compression ratio. The currently notable six stroke engine designs in this class include two designs developed independently: the Beare Head engine, invented by Australian farmer Malcolm Beare, and the German Charge pump, invented by Helmut Kottmann.
1. TFC:-Total fuel consumption in Kg/Hr
2. SFC:-Specific fuel consumption in Kg/Kwhr
3. BP:-Brake power in Kw
4. TDC:-Top dead center
5. BDC:-Bottom dead center
6. IVO:-Inlet valve opening
7. IVC:-Inlet valve closing
8. EVO:-Exhaust valve opening
9. EVC:-Exhaust valve closing
10. N:-Engine speed at final drive shaft to the wheel in rpm
11. P:-Load in Kg
12. T:-Time for 10 cc fuel consumption
HISTORY OF SIX STROKE ENGINES
As mentioned earlier there are two approaches to study about six stroke engines,...