# Cooling system transfer function

#### cdennis414

Joined Dec 19, 2012
15
Hello,

I am doing a work-based project for college

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#### ci139

Joined Jul 11, 2016
1,873
? which way transfer function
? the external flow rate versus no flow at the motors water jacket

#### ci139

Joined Jul 11, 2016
1,873
? so as it may be read out your radiator won't get totally blocked off and there remains some motor to radiator heat exchange
as so
? do you include this flow rate as well about https://apureinstrument.com/blogs/select-the-right-water-flow-meter/ --e.g.-- you need to characterize you engine and cooling system for various flow rates and temperatures of the heat transfer media (water) . . . or at least theoretically . . . otherwise you need monitoring the temperatures and make live decisions about the cooling adjustments

a block diagram (with sufficient context) of your setup would not hurt

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#### MrAl

Joined Jun 17, 2014
9,558
Hello,

I am doing a work-based project for college; it is control and instrumentation subject. I am trying to create an additional cooling system for a generator diesel engine. The problem is that during the summertime the radiator getting blocked by pollen and gets overheated and shuts itself down.

I am trying to introduce an additional water spray system that would spray some water on the radiator to prevent the shutdown. So, when temperature reach 90 degrees water pumps starts, solenoid valve opens and water spays through the nozzle.

My aim is to mathematically model the system and then simulate it in MATLAB. However, I am struggling to get a transfer function for the system. Any suggestions how get around it?
Hi,

This sounds like an on/off control rather than an actual linear control.
You say when the temp reaches 90 (is it F or C) the water pump starts. Does that mean the pump is controlled in a linear fashion or just turned on?
If linear that would mean the speed of the pump is varied but if just on/off then the pump simply turns on when needed and off when not needed.
Sometimes a simple on/off system is enough, with some added hysteresis. That would be like a home thermostat used to set the house heating.

How are you modeling the Qe and Qa and even the other, or are you?

A practical question is, where is the water going to come from?
Some air conditioners use this technique but they get the water from the normal condensation that other AC units just drip out the back and down onto the ground. The water spray increases the overall cooling efficiency of the AC unit.