Engine cooling system with overload handling capability

An automotive vehicle powered by an internal combustion engine, said vehicle comprising:

• (a) an engine generating fluctuating amounts of waste heat;
• said engine being adapted for transferring said waste heat to a liquid coolant;
• (b) a radiator adapted for transferring average amount of said waste heat from said liquid coolant to ambient air but not the peaks of said fluctuating amount;
• (c) a water pump arranged to circulate said liquid coolant between said engine and said radiator;
• and
• (d) phase change material (PCM) placed in thermal communication with said liquid coolant;
• said PCM adapted for absorbing heat from said liquid coolant during said peaks, and for transferring absorbed heat to said liquid coolant at times other than the times of said peaks;
• wherein:
• said cooling system is arranged to maintain the temperature of said liquid coolant near a predetermined normal operating temperature T0, and said PCM has a melting temperature Tmelt which is higher than said predetermined normal operating temperature T0.

An engine cooling system for a liquid cooled internal combustion engine;

• said engine cooling system comprising an engine, radiator, heat accumulator, and a water pump;
• said water pump being arranged to circulate said liquid coolant between said engine and said radiator and through said heat accumulator;
• said engine cooling system arranged to maintain the temperature of said liquid coolant near a predetermined normal operating temperature T0;
• said heat accumulator comprising a phase change material (PCM) having a melting temperature Tmelt at least 5 degrees Centigrade higher than said normal operating temperature T0;
• and said PCM being in a thermal contact with said liquid coolant for transient heat exchange therewith.

A method for cooling an internal combustion engine (ICE);

• said method comprising the acts of:
• (a) providing an ICE adapted for being cooled by a liquid coolant;
• (b) providing a radiator adapted for transferring heat from said liquid coolant to ambient air;
• (c) providing phase change material (PCM) in thermal communication with said liquid coolant;
• said PCM having a melting temperature Tmelt and a solidification temperature Tsolid;
• (d) operating said ICE;
• (e) circulating said liquid coolant between said ICE and said radiator;
• (f) maintaining said liquid coolant at a predetermined operating temperature T0 which is at least 5 degrees Centigrade lower than said melting temperature Tmelt of said PCM;
• (g) increasing the output of said ICE;
• (h) allowing the temperature of said liquid coolant to rise above said melting temperature Tmelt of said PCM;
• (i) transferring heat from said liquid coolant to said PCM;
• (j) melting at least a portion of said PCM;
• (k) reducing the ICE output;
• (l) allowing the temperature of said liquid coolant to decrease to a value lower than said solidification temperature Tsolid of said PCM;
• (m) transferring heat from said PCM to said liquid coolant;
• and
• (n) solidifying said PCM.

A heat accumulator for use in a liquid cooling system for an internal combustion engine;

• said liquid cooling system being arranged to flow a liquid coolant at a normal operating temperature T0;
• said accumulator adapted for flowing said liquid coolant therethrough;
• said accumulator comprising a PCM in thermal contact with said liquid coolant;
• said PCM having a melting temperature Tmelt and a solidification temperature Tsolid;
• said melting temperature Tmelt being at least 5 degrees Centigrade higher than said normal operating temperature T0;
• and said solidification temperature Tsolid being at least 5 degrees Centigrade higher than said normal operating temperature T0.