Engine Cooling System

Published on 22 Nov, 2013

Cooling systems deployed around the periphery of the IC engines of vehicles play a vital role in safeguarding the engines from overheating. It involves the following components:

  • a. Fluid – Acts as a carrier for transferring heat from the engine
  • b. Hose Pipe – Contains the coolant
  • c. Pump – Forces the coolant to flow within the hose pipe to the periphery of the engine
  • d. Thermostat – Measures the temperature of the coolant/engine
  • e. Radiator – Located proximal to the engine and includes multiple pipes arranged in a specific manner for cooling the hot fluid
  • f. Fan – Assists the radiator in cooling the fluid

The below diagram depicts a typical construction of the cooling system.

typical construction-cooling system

During operation, a coolant is circulated to the periphery of the engine parts through hose pipes. The coolant absorbs the heat from the engine parts and transfers it to the radiator. Within the radiator, the coolant flows through multiple pipes arranged in a specific manner. These pipes containing the coolant at higher temperature are cooled by a fan adjoining the radiator. The coolant is then circulated back to the engine parts and the cycle repeats.

With an objective to effectively cool the IC engines, considerable research have been performed on the components of the cooling systems. Since the last five years, nearly 1,000 patent publications have been published every year. Interestingly, the research has been consistent and is slowly increasing. The chart below depicts the filing trend for the last five years.

Engine Cooling System Filing trend

The research focuses primarily on the design aspect of the cooling systems, with additional emphasis on developing the radiators. Most of the research has been performed by OEMs; Toyota and Honda motors top the list with approximately 500 and 200 patents filed in the last five years, respectively. Interestingly, Denso Corp, a component manufacturer, is actively filing patents within the domain.

Competitive Landscape

Specifically, the research by the top assignees has been toward addressing problems such as:

  • Temperature rise in multiple exhaust ports: With increasing number of turbocharger-based engines having two or more exhaust ports, considerable design modifications are made to effectively dissipate heat arising from these ports.
  • Temperature rise in non-formal engine structures: To optimize the efficiency of engines, the trend is toward varying the wall thickness of the cylinders. Therefore, it is essential to design accordingly the flow of the cooling systems, i.e., lesser amount of fluid in thick sections and high amount of fluid in less thick sections.
  • Complex structure of cooling systems: To reduce the manufacturing costs of the cooling systems and optimizing the space requirements, the companies are developing cooling systems with simplified structures.

In terms of the preferred geographies for patent protection, Japan, the US, Germany, and China are the key markets. Japan dominates the research space with approximately 1,200 inventions originating from the region. The graph below depicts the distribution:

Origin of Invention Engine cooling system

In light of the above, the research activity is expected to rise further and there is a high probability of component manufacturers bringing in innovation into the area. The growth can be attributed to global factors such as cost optimization, need for powerful engines with higher cooling requirements, OEMs outsourcing the design to component manufacturers, and space optimization within the vehicles.