Specifications

Completely balanced engine by design

The complete balance of the conventional engines can be achieved if they are 6 in-line arranged.

In contrast, the CoAxial engine is completely balanced with only two operational pistons. The conrod assemblies of the CoAxial engine move synchronously along the cam axis of rotation with the same velocity and acceleration. But the direction of the conrods’ accelerations are opposite. Thus these inertia forces quench each other.

Downsized but with fewer cylinders – not smaller cylinders

Better ratio: (Displacement) / (Heat exchange surface). Less heat losses. Greater efficiency.

Superior efficiency at lower hazard emissions with less after treatment

The CoAxial engine thermodynamic cycle can approach to the ideal thermodynamic cycle much closer than the thermodynamic cycles of any conventional ICE due to the greater flexibility of the CoAxial engine pistons motion (see benefits). Thus the longer piston dwelling around the dead centers allows better completion of the combustion. And consequently, the products of uncomplete combustion such as CO, CH and soot will be significantly less. Particularly, the NOx emissions could be reduced by EGR approach, lowering of compression ratio or better after treatment. It has always been an optimisation task finding the proper balance between efficiency, emissions and other vital engine parameters. In the case of the CoAxial engine, the optimal efficiency can be improved by additional factors indicated in the BENEFIT tab. These factors are beyond the reach for the conventional ICE. It has been proved by researchers in the field that the engine efficiency can be increased by at least 5% only through manipulating the piston motion law.

Superior combustion by design for wide range of difficult to burn fuels

In general, the alternative fuels combust slower than conventional fuels. Therefore longer piston dwellings around their dead centers is highly beneficial in case of alternative fuels utilisation in the CoAxial engine. The efficiency improvements will be even greater than those achieved with the conventional fuels and engines.

Aggressive valve operation possible without issues for the timing mechanism

Rapid valve opening/closing is very important factor that improves engine efficiency but at the same time, the rapid valves response can destroy the structural integrity of the valve-timing mechanism prematurely. The unique CoAxial engine design allows achieving much faster valves lifts/drops without issues for timing mechanism. The huge cams profile of the timing mechanism provides opportunity for gradual cam slopes and optimal valves’ motion. In this way, the combination of longer piston dwelling around BDC and late exhaust valve opening allows longer utilization of the working fluid pressure without losses during the consequential exhaust stroke.

Atkinson cycle effect achieved by equal strokes

The Atkinson effect in the modern conventional engines is realized by late intake valve closing. Thus the cylinder length is oversized for the sake of the Atkinson effect achieving.

The CoAxial engine though does not need extra cylinder length for the same purposes. It just uses the piston duelling around BDC for free exhaust gas flowing out of the cylinder caused only by pressure difference between the working fluid in cylinder and ambient air.

Reduced friction leading to higher efficiency and wider ambient temperature limits of operation

The most of the CoAxial engine components contact each other through almost slipless rotation such as contact between the conrods and cam profiles and thus the friction is brought to much lower level than the conventional engines. As result, huge amount of the parasitic energy spent for lubrication of the conventional ICE is saved in the CoAxial engine. In this way, the CoAxial engine efficiency is boosted by both – low friction losses and less lubrication energy expense.

The only extra friction occurs in the CoAxial engine output gear transmission in case of the pure mechanical output application. The typical losses of the gear transmission though are within 1-1.5%. Therefore, it is obvious that the energy savings are much greater than the output transmission causes. Furthermore, the output transmission losses could be completely eliminated if the pure electrical output version of the CoAxial engine is selected.

Four stroke performance achieved with single revolution

In contrast with the conventional ICEs, the number of strokes per single revolution is 4 in the CoAxial engine or theoretically greater. As result, the output torque is at least twice greater than the conventional ICE. Therefore the output gear transmission could be considered as first one in the consequential gear box that actually provides better adaptation between the CoAxila engine and given vehicle transmission. It is possible also direct implementation of CVT instead of the output shaft.