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I won't say the name of the manufacturer... i'll just say that it's name has a greek character and it produces heat exchangers around the world. The mentioned methods are specified on the heat exchanger's manual. Regards, JuanMC

Hi! There are several titanium-plates heat exchangers in our facility. By one side of the exchanger (cool fluid) runs non-treated water, taken directly from a little dam. By the other side runs treated water that cools an electric generator. Due to the level variation in the dam, sometimes we...

Thanks Deltathx, Ed and DYV. Let me explain a little further our problem: I'm talking about heat exchangers of a little hydroelectric plant (50 Mw). As I said before, there is treated water running by one path, and non-treated water on the other side. The non-treated water cools the...

Thanks for your answers Uncle, Pmover. I have heard about magnetic conditioners, so I thought there could be something similar to deal with our sediments. Now, after i read more about the mag-conditioners, i've realized that those would be useless for our intentions. I guess we must use the...

You are right btrueblood. But we're thinking about changing the characteristics of the plates, looking for a decrease of the "adhesiveness" (sorry, i'm not sure if it is the right word to say it) of the sediments, so we wouldn't need to change or clean nothing at all. Thanks!

Hi! We have several plates heat exchangers in our facility. In a closed circuit, runs treated water that cools an electric generator, and in an open circuit runs non-treated water, on counter flow. Due to the high quantity of sediments in the open circuit, the thermal flow decreases almost...

Thanks a lot!

Hi! What methods are there to clean the inside of the tubes of an oil cooler?. The supplier recommends compressed air, not more, but the oil cooler has been working with low quality oil, and it hasn't had an adequate maintenance since it's installation. ¿Are there any chemical solutions or...

Hi! We need a AC/DC converter, to feed 8 DC motors, 125Vdc - 2 kW each one, from an input of 480Vac. Does anybody know a supplier of this type of AC/DC converters?. I have found just pc and low voltages converters or low power (12 kW maximum). ¿How much could this cost? Sorry, if it's a silly...

Thanks to everybody. Willard, thanks, but we can't use the heat. It is the refrigeration of the lube oil for bearings for an electric generator, there is no use for the heat. I was wondering if it was better; The system has had a lot of miss-designs (piping, thermal capacity under-sized, and...

I have another easy question about fans... well, I hope it is an easy question... We have in our facility an oil-cooler; it works with two axial blowers, suctioning air through the finned tubes and sending it out directly to the atmosphere. We could invert the rotation of motor and change the...

I'm having difficulties with something similar... i'm not changing the flow rates, but i'm pre-cooling one side, keeping the flow rates constant. Try this: * Take the initial Q for one side. If you increase the flow rate, the temperature should decrease => Q = mass flow x Cp x (Tout-Tin) * Do...

Hi! I want to build an evaporative cooler to increase the efficiency of an HEX (shell & tubes). I was checking the ambiental studies and found the average relative humidity of this area: 81 to 92%. ¿Could I work with an evaporative cooler? I was checking psychrometric charts and the difference...

I haven't noticed that there were no latent heat values, sorry. I found the page looking for viscosity and specific heat at different temperatures. I think that those crazy units are related with the API gravity (Petroleum standars), in the first sheet. About the density, I just took the...

Hi curve Try this: http://www.xlrotor.com/Lubricant_properties_calculator.XLS I wouldn't trust 100%, but it has been useful for me. Best regards, JuanMC

About this "in an air-cooled oil cooler the oil side generally controls the overall heat transfer coefficient" I think that that is related to the material of the tubes and the fluid's characteristics: viscosity, density and type of flow (laminar or turb.) We need to consider the air density...

I am not designing a new exchanger. I'm trying to increase the efficiency of the original exchangers, by cooling the air used by the fan. I could know this temperature (air at the entrance), but my desired oil exit temperature is the coolest possible with the minimum modifications.

Yep, that is what i'm trying to determine by doing all that. I'm supposing that UA remains unchanged, but i need to determine the variation in heat transfer (by the variation of the air-inlet temperature), before selecting a way to modify the system. dcasto, thanks. If i can't get enough heat...

I have the iteration process in a .xls sheet, if someone is interested. Thanks again.

I have a heat exchanger, (shell & tubes) fan-cooled. It cools oil from 55 °C to 45°C. I would like to increase the net heat transfer with the minimum changes in the system. I have determined the additional heat stream that i need, but don't know how to relate it with the heat exchanger. This is...