In order to avoid an engine’s thermal fatigue failure or lowering the engine’s performance due to engine oil deterioration, the oil must be changed when it loses its protective properties. Also, unnecessary oil changes should be avoided for environmental and economic reasons as still active additives left in the oil may react with the environment. Today, no built-in system exists in the world which online can monitor an engine’s lubricant oil condition. We change the lubricant oil based on experience by looking at oil’s sample or after 3000 km of travel which is reference set by the oil manufacturer. But with this we cannot predict if the oil is contaminated, if additive packages are depleted, if it is low or still they are active. Also we have tested oil sample for each 500 km travel of vehicle and we observed that lubricant oil losing its all properties after 1500 km travel which is far below what the oil manufacturer has set i.e. 3000 km.
The solution with which we come up to solve this problem is as follows: all the engines come up an oil filling cap or dipstick made of plastic or steel material and is dipped in crankcase oil, dipped in plastic or steel portion of oil filling cap or dipstick can be replaced and made by shape memory alloy base sensor. When we heat the shape memory alloy, it returns to its pre-deformed shape and based on this principal proposed oil monitoring system works. Now, after travelling a certain distance oil in the crankcase getting heated up to a certain temperature and so the shape memory alloy based sensor dipped in the oil will be getting heated. As oil is deteriorating day by day, its temperature also increases more than previously and so the rate of shape change of the sensor also increases rapidly. This rate of shape change is dependent on oil temperature. Now, oil viscosity talks about oil quality and its life and is directly proportional to temperature. This shape memory based Sensor integrated with oil filling cap or dip stick can be put in the engine crankcase and temperature dependent rate of change in shape can be measure and so viscosity of oil. This can be converted into suitable signals with the help of programmable coding language and can be sent to the vehicle dashboard in the driver’s cabin via Bluetooth where the driver can easily see the oil change signals colored with Green indicates oil is in good condition, Yellow indicates oil is about to deteriorate and Red indicates oil needs to be replaced.
This is a novel system for online monitoring of oil which improves engine and its components performance, public safety, vehicle/engine security and saves time, money and lives of animals and crops keeping the environment healthy. Above benefits can be achieved without any change in existing design of the engine. Only the oil filling cap and dipstick need to integrate with the shape memory based sensor which will be dipped into the engine oil.