Improvement of the automobile engine braking indices
Operation of the automobile diesel in the conditions of idling is considered in the report. Analysis of theoretical and experimental researches into operation of the diesel in the conditions of the automobile braking by the engine is given. In connection with the rise of volumic power of diesels by means of turbo-supercharge and cooling the supercharging air, inconsistency between the effectiveness of existent engine braking system and the modern requirements is shown. It is ascertained, that a limiting factor for increase of the automobile engine braking power in the conditions of the forced idling at closing of the outlet collector is self-opening of the outlet valve in the cycle of suction. As a result of this a counter-pressure in the cycle of ejection and consequently the losses on the gas exchange decrease, that leads to decrease of braking power of the engine brake-decelerator. A scheme of the elaborated construction is given, which eliminates self-opening of the engine outlet valve in the conditions of the automobile braking by the engine. Thereat, possibility of sharp rise of the engine braking power is shown, that confirms possibility of not less effective use of the automobile engine in the conditions of braking than in the regime of traction.