Split type superhigh-expansion-ratio engine and adjustment and control method

Abstract

The invention discloses a split type superhigh-expansion-ratio engine and an adjustment and control method and belongs to the field of engines. The split type superhigh-expansion-ratio engine comprises a gas compression device, an expansion acting device and a high-pressure pipe. A high-pressure gas tank is arranged between the gas compression device and the expansion acting device and is in gas circuit connection with the gas compression device and the expansion acting device through the high-pressure pipe. The air cylinder volume of the expansion acting device is greater than the air inlet natural volume. The split type engine is different from a common Otto-cycle internal combustion engine in that the gas compression stroke is moved into the gas compression device out of an acting cylinder and the engine is provided with the high-pressure gas tank for achieving buffering, pressure stabilization and temporary storage of compressed gas. By means of a certain technical scheme and the adjustment and control method, the engine can achieve the Atkinson cycle easily at the low cost in all working conditions; and in addition, the expansion ratio can be far greater than the compression ratio under the working condition of small acceleration, thus, oil consumption is remarkably lowered, and the effect is particularly obvious under the working condition of the small acceleration.

Description

technical field [0001] The invention relates to the field of engines, in particular to a split-type super-large expansion ratio engine and a control method. Background technique [0002] In a conventional Alto cycle internal combustion engine, four strokes are performed in each cycle: intake stroke, compression stroke, power stroke, and exhaust stroke are all completed in one cylinder, and the compression stroke and power stroke of the piston are equal and less than the length of the cylinder , the compression ratio and expansion ratio are equal and fixed. Result 1. After the piston’s working stroke is over, the gas in the cylinder still has a relatively high residual pressure, and the high-temperature gas cannot fully expand and do work, resulting in energy waste, which is especially serious under the condition of large throttle; It can also be seen from the characteristic curve that at the same speed, when the torque (throttle) is above the mid-high value, the greater the...

AI Technical Summary

Problems solved by technology

The disadvantage is that high load will lead to insufficient engine power. Under low throttle conditions, the compression ratio will drop more, requiring a complex valve mechanism, and the compressed gas cannot effectively cool down. When used in gasoline engines, the compression ratio is low and the fuel efficiency is low;

[0007] Chinese patent CN 102472152 A discloses a split-type circulating air hybrid engine with ignition and inflation modes: it is a split type, that is, compression and work occur in different cylinders; its air distribution mechanism and air distribution control are quite complicated, and the compression ratio is not fixed , unstable, not conducive to the normal operation of the engine, and low fuel efficiency;

[0008] Chinese patent CN107407190A discloses a split cycle engine: it belongs to the split type, its overall structure is complex, the valve mechanism and gas distribution control are quite complicated, the compression ratio is not fixed and unstable, which is not conducive to the normal operation of the engine, and the fuel efficiency is low

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