The patent that will lower the emissions from the exhaust of cars with a diesel engine

A development by a researcher from Ben Gurion University, which has now been granted a patent, may reduce the risk to health and the environment from car smoke * The idea is based on a phenomenon of particles clustering in a fluctuating flow field

An idea conceived by Prof. David Katushevsky from the Department of Biotechnology and Environmental Engineering at Ben-Gurion University has become an applied patent, which may reduce the risks to health and the environment arising from the smoke particles emitted from diesel engines. The research partners are Prof. Eran Sher from the Department of Mechanical Engineering, and PhD students Michal Rosel and Tal Shaked from the Environmental Engineering Unit.

The idea is based on a phenomenon of particle clustering in a fluctuating flow field. This phenomenon is found in nature, for example in the formation of sediment blocks (mud) in the sea. The development of a mathematical model to analyze the phenomenon led to the thought that the model could be used in the opposite way, namely to control particle aggregation by creating the appropriate flow conditions. Following this, the idea arose that this phenomenon could be exploited in the context of the smoke particles emitted from a diesel engine as they move through the exhaust pipe. The idea is that such a grouping causes the particles emitted from a diesel engine to stick together and thus cause a decrease in the number of the smallest particles.

It has long been known that submicron particles emitted from diesel engines are the main source of concern regarding air pollution from these engines. The smaller the particle, the higher the health risk and this is for two reasons: one, it is easy for a small particle to penetrate the respiratory tract, and the second, such a particle stays in the air for a relatively long time, which causes us to be exposed to it for a long time.

Based on the theory, an exhaust pipe with a special geometry was designed for a diesel engine. The computational simulation and the experiments show that the new exhaust does cause a reduction in the number of the smallest particles at the expense of an increase in the mass of the larger ones. Increasing the particles will lead to the possibility of their capture by simple filters, but beyond that - even if they are released into the air, they will be less dangerous to health and the environment.

The researchers continue to develop different versions of the system in the laboratory at Ben-Gurion University and hope that there will be a response from car companies to use it. The system is expected to be useful on the one hand, and on the other - cheap and simple to implement.