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Dear CCP4bb users, I would like to thank everyone who replied my email. I am posting all the answers I got for the following question: I have a rotating anode that requires an input of 20 L of water per min at 18-20 celsius degrees. I have to redimension an old chiller for this purpose and I was wondering if someone have any idea about the temperature of the output water when rotating anode is working properly. I know the answer will depend on each rotating anode type but any reference will be a starting point for my case (ps. i could not find such answer in the manual). Is a raise of 5 celsius degrees a common value? Here are the answers. >>>>> Deena Oren You could try contacting the chiller supplier. My contact person was: Doug Wagner of Haskris [EMAIL PROTECTED] He was very helpful. >>>>> >>>>> Simon Phillips I remember having to face this a few years ago, but we managed to find the spec sheet for the generator. I think you should expect more than 5 degrees temperature rise, depending on power, and perhaps more like 15 or 20 degrees. You should be able to calculate it from the power input. I am not in the lab right now so cannot look up the correct information, but I think the figures above are in the correct ball-park. >>>>> >>>>> Anastassis Perrakis I think a raise of 5 deg is a good value - for a pretty good anode. we have a 12 year old fr591; it does about 5 at 4 kW and about 10 at 6 kW (our cooler cannot handle that and eventually it crashes after 5-6 hrs) >>>>> >>>>> Michael Bannwarth I would be myself interested what other ccp4bb users think about this matter, but my thought was that a rotating anode has e.g. 5.4 kW means it can deliver 5400 J per s not only to generate x-rays but also mainly heat, which means, since the heat coefficient of water is 4.19 J/(g*K), that it can deliver each second 1.290 L*K heated water or per minute it can heat up 20 L water by 3.87 K or centigrades respectively. So I would consider a raise in the 5 celcius degrees range a common value. But I do not really know it or measured it myself. >>>>> >>>>> Mark Agacan I have mains-supplied water running through our rotating anodes (M007 and M007 hf), which goes into the chiller at around 10 degrees Celsius and exits the generators at around 20 degrees C, so, in my opinion, a raise of 5 degrees C would be acceptable. However, this water goes straight down the drain after exiting the anode, so our water chillers are not burdened with cooling relatively warm water. An old chiller may find this a bit too much work. >>>>> >>>>> Ana Luísa Moreira de Carvalho In our group, we have a FR591 rotating anode from Nonius. The primary water goes in at 15 C and comes out at 19 C, so i think a 5 celsius degrees increase is normal. >>>>> >>>>> Boaz Shaanan Rise of 5 deg. C is fine. We have our RA (Rigaku RUH3B) running at 5 kW, the entrance temp. is 18-19 deg. C and exit temperature is 24-25 deg. C. The volume/minute capcitity supplied by the chiller (Neslab HX-750) is also 20 L./minute. >>>>> >>>>> Peter Moody Rigaku RU2HB 50kV 100mA 0.3 focus so thats 5kW in the tube, plus TMP and transformer heating. I read 20 C, input 24 C output (thermocouple taped to the copper pipe) so 5 C should be fine... I don't know our flow though! >>>>> >>>>> Matthew Franklin Here's some related numbers that I collected when Rigaku and I were trying to diagnose a chiller problem in my then-new 007HF. At 1.2 kW (full power; 40 kV/30 mA), the generator was dumping 2.2 kW of heat into the closed water loop of the chiller. Flow was 1.1 gpm, and water temp into the generator was 20 C, water temp out was 35 C. We eventually determined that the Haskris R033 (1/3 hp) was too small to take the heat load, even though a similar system had worked in other installations. Replacing the Haskris with a 3/4 hp model allowed the chiller to handle the heat from the generator. This was a refrigerated, water-cooled Haskris system: a closed loop of circulating water cooling the X-ray generator, with a refrigeration system taking the heat from the closed loop and dumping it into a city water open loop. I would say that, for this system, the 1/3 hp chiller was marginal (worked for some people, not for me) while the 3/4 hp chiller is more than adequate. We never did figure out where the extra 1 kW of heat came from; the only things that the water cools are the anode and the tube tower. >>>>>
