How does it work a centrifugal pump?

Back on track with our Tempco tutorial video series in this new year, let’s talk about fluid motion, being it water, oil or other kind of fluids. In particular let’s talk about how a centrifugal pump works.

A centrifugal pump is a hydraulic machine in shape of a rotative pump, that can be directly coupled with an electric motor or via a joint. As it often happens, Tempco customers ask how centrifugal pumps should work in order to operate properly ‘in range’.
If we look at a common functioning curve of a centrifugal pump, flow rate and pressure values happen to be inversely proportional: when flow rate is at its maximum the pressure is minimum, viceversa maximum pressure corresponds with minimum flow rate.

pompa centrifuga pressione portata

With the outlet of the pump completely closed, with water delivery off, we’ll thus have maximum pressure value. Customers often contact us telling the pump is undergoing a huge effort while pushing water at a high pressure. If we take a look at the electric power absorption curve of the motor, we’ll see that the power input of the electric motor is inversely proportional to the pressure value generated by the pump.

rendimento pompa centrifuga

Otherwise, a maximum pressure value is combined with minimum power consumption of the electric motor, which instead goes maximum when the pressure is at its minimum.
The reason relies upon the mechanical functioning of a centrifugal pump, which moves the maximum flow rate when the pressure is at its minimum, pushing high weights of fluid putting the electric motor under big efforts, meaning high power consumption.

To make an empirical example, the same happens when we try to move a huge weight for a short space distance, it takes a very big effort.

The consequence is that in case the decrease of pressure gets no limitations, letting the pump operating without pressure charge, the pump will exceed its operating range, triggering the intervention of the thermal protection of the electric motor.
Pumps have indeed a limit toward upper pressures, since they cannot exceed a certain maximum pressure, but on the other side they can push flow rates much higher than the design value of the electric motor, setting the motor in out of range stress, that causes the intervention of the thermal protection to avoid the burn out of the motor itself.

To avoid this issues, in our plants we usually put a gate valve on water delivery, which increases the pressure while closing it, making the pump operate back in the correct range, with proper design flow rates, thus ensuring that the motor won’t absorb power in excess.

Measuring energy efficiency of data centers with the PUE

While the quantity of data collected by sensors and IoT devices increases, as well as the computing power required by AI and machine learning applications, the energy consumption of data centers is becoming more and more a very hot topic.

Hot as it’s in fact the amount of waste heat produced by servers and IT equipments in their operations, so that cooling systems in data centers are a crucial asset to ensure the efficiency and reliability of a data center. There are some methods of calculating energy efficiency in data centers, the most popular being the PUE metricPower Usage Effectiveness -, as described by Matteo Mezzanotte in this very interesting Submer blog’s article. The PUE was introduced by the Green Grid, a non profit consortium of IT professionals aimed to improve energy efficiency and lower the environmental impact of data centers.

data center cooling

The PUE is obtained as the ratio of the total amount of energy used by a data center facility, including utilities such as cooling, lighting and energy losses by UPSs, to the energy actually delivered to computing equipment. Green Grid also introduced its reciprocal measurement, the DCIEData center infrastructure efficiency, defined as the ratio of total amount of energy consumed by the IT equipment to the overall energy consumption of a data center.

An ideal PUE is 1.0, with all the power consumed by the IT devices. According to Green Grid, the average PUE value of data centers around the world is 1.8, meaning that about the 45% of all the energy consumed by a data center is employed for non-computing purposes.

PUE data center energy efficiency

Submer also created a SmartPUE, a useful tool to evaluate a data center efficiency by calculating its actual PUE. We also re-launch a suggestion made by Submer to the Green Grid to include the positive effect of the recovery and re-use of waste heat to the PUE and DCIE equations, as well as focusing the benefits of the adoption of immersion cooling systems in data centers. Cooling servers by placing them into dielectric baths, a kind of application we also develop in Tempco with TCOIL immersion cooling systems, allows indeed to achieve several benefits, above all an important reduction of energy consumption when compared to air cooling solutions, a more stable and constant thermal environment and, last but not least, physical space saving which allows to increase IT hardware and computing density, achieving better PUE values.

Immersion cooling of servers also brings a lot more benefits, as this other very much interesting article on the submer blog explains. We would also like to add that immersion cooling allows to employ fluids at a less low temperature compared to air cooling solutions in data center. That’s a very interesting topic, which we’ll gladly approach more in depth very soon.

raffreddamento a immersione data center

Tempco Wishes! Happy Holidays from Tempco!

It has been a year full of challenges along with great satisfactions for Tempco, a year that brought many important innovations that carry us into a 2020 full of energies and wiling to grow up always further with you!

And as every year, we would like to wish you a Very Merry and Warm Christmas and an Amazing New Year!

Tempco happy-holidays 2020
Happy Holidays from Tempco!

Energy saving and IoT, chatting with Tempco part. 2

Follow-up of the chat we did with La Termotecnica, let’s go on talking about energy saving, a really main driver in all of Tempco’s projects. In order to maximize energy saving in industrial thermoregulation, cooling and heating solutions, we’ve developed a series of thermoregulating units that employ power modulation on electric motors. Whenever is it possible, we always try to use fans and pumps with EC motors, equipped with inverters enabling to adapt pressure and flow rate to the effective needs of the process.

We have also developed a series of thermoregulating units with electric heating equipped with continuous variation of the power capacity, aimed to provide customer the effective power required in a just-in-time basis, exactly when it’s needed.

Free cooling systems are another application we develop since many years to achieve energy saving in industrial applications. A new project is instead the iTempco platform. The project was born in January 2019, but we were thinking about something similar for a long time yet: iTempco is a condition monitoring platform of our units, which allows to remotely check via cloud both the functioning and the performances of our thermal machines, aimed to implement predictive maintenance services. In addition, it allows us to understand how our equipments work, and how they are sized referred to real customer’s needs, providing us a feedback loop to optimize the engineering of our machines, in a data-driven mode.

Finally, this Tempcoblog you are reading is something that goes on since 15 years, aimed to open a contact window with our customers where we can give updates on our latest solutions for heat exchange and energy recovery problems. I can take this opportunity to say a big Thank you to everyone who is still following us with such continuity after all these years, for your attention and contribution! And also for the nice feedback we’re having for the Video series that during 2019 we started uploading on our Tempco YouTube channel.

Looking at the future of Tempco, we have very clear ideas: we want to keep growing enormously, in order to be able to give customers better and better support in their energy saving and temperature regulation applications. The Tempco team is really a close-knit and skilled group, and it allow us to react with very short times to market demands. In Tempco we love challenging projects, because this is not really a job for us, it is truly a passion!

A quick chat with Tempco

A few weeks ago I had the pleasure to chat with La Termotecnica, the reference technical publication for the Italian energy and thermal energy technology industry.

To introduce Tempco, let’s say we are a company that supports production industries to achieve thermoregulation, cooling and heating tasks in their production processes, leveraging energy recovery. Nowadays Tempco systems have several important references, and can be found in the CERN’s particle accelerator in Geneva but also in automotive ovens employed for the body curing of carbon fibre structures of F1 vehicles. Our solutions are also a crucial asset to cool down carbon-ceramic brakes that slow down jets on aircraft carrier’s decks, as well as for thermoregulating active ingredients employed in a variety of pharmaceutical drugs.

The special production is a main part of our portfolio, following a philosophy that we’ve called SCF, standard custom flexibility. Starting with standard products allow us to customize solutions aimed to meet individual customer’s needs, solving their problems in thermoregulation, heating and cooling achieving the maximum efficiency, flexibility and with shorter development times.

A main place in our offering is held by plate heat exchangers, let’s say we love them a lot! We have our own production line of plate heat exchangers, both in gasketed plate type, starting from DN32 up to DN500, and in brazed plate type, copper and nickel. We also offer a special series of brazed plate exchangers, designed to withstand water hammer effects and extreme temperature variations, and brazed exchangers that resist pressures up to 100 bars and high temperatures up to 900° C.

Finally, an important place is also held by our TREG thermoregulating units, born as a natural extension of our heat exchangers core business. Customers that used to see our expertise in plate heat exchangers started asking us if we would have been able to assembly them in a thermoregulation system. From there it has been an easy step forward for us, simply implementing a production system for thermoregulating units, special ones for power plants especially. Then we went even further, by obtaining the Atex certification, so that we can also offer thermoregulating units and skid systems suited for explosive environments.

Temperature regulation of wheat grains

TCOIL dimple jacket exchangers in application for the cooling and heating of wheat grits, coming from silos or aimed to be stored in silos. This is a very common application in north-American markets.
Wheat grains are indeed heated to get dry before these are stored, or otherwise cooled when coming from silos that are too hot to allow the wheat to be exposed to ambient air.

dimple jacket wheat grains cooling

The TCOIL exchanger with spot-welded and inflated plates in this case is composed by a battery of 30 plates with double dimple, each plate has a size of 1000 x 1000 mm and the plates are mounted with 20 mm pitch. The material is AISI 304, with thickness of 12/10 mm of the metal sheets and two flanged connections type DN 80 PN10 with square collector.

Tempco TCOIL raffreddamento frumento

The dimple jacket heat exchanger battery is immersed in a parallelepiped shaped vessel, within which wheat grains are poured. Low pressure steam flows inside the plates to achieve heating, while refrigerated water at a pressure of 3 bar is employed for the cooling task.
A very similar application has been realized for the cooling/heating of granular plastic materials.

raffreddamento materiali plastici TCOIL

dimple jacket plastic grains cooling

Drift separators in cooling towers

Third episode on our video series focused on cooling towers components, this time is the turn of drift separators. Drift separators are components employed in cooling towers to limit water consumption, installed above the nozzles that provide the distribution of water. These components are intended to capture all the water droplets that otherwise would be drafted away by the air flow generated by the forced ventilation coming from fans inside the evaporative tower.

Construction materials are similar to those employed for filling packs, being traditional plastic materials such as PVC and polypropylene.
Thermoformed droplets eliminators is the most employed typology. Also parallel fins separators do exist, but they offer slightly lower efficiency and are usually employed in other types of separation systems, not really much in evaporative towers. In the past, droplets separators used to be made in wood, but nowadays this is an obsolete kind of construction no longer employed.

Ferrari intercooler, some ‘dirty trick’ cooling?

Rivals teams in F1 are moving forward some doubts about the legality of the cooling system in the Ferrari power unit. That’s what this interesting article I found online is talking about. These are just hypothesis, nothing has been proved, but the presumed anomaly should refer to the employ of oil within the intercooler which cools down the intake air coming from the turbocharger and aimed to increase the output of the internal combustion engine.

Ferrari intercooler intake air cooling

An intercooler is a heat exchanger, usually air/water or air/air type, installed between the turbocharger and the combustion engine. Its function is to cool intake air charge, increasing the efficiency of the combustion. The turbocharger compresses the induction air employed in internal combustion engines to improve their volumetric efficiency. As a result, the compression process raises intake air temperature while reducing its density. The intercooler removes the heat of compression decreasing intake air charge temperature, sustaining the use of a more dense intake charge into the engine, increasing the output of the power unit. In addition, the lowering of intake charge air temperature also avoids the danger of pre-detonation.

intercooler Ferrari

The cooling circuit of an intercooler is composed by a quantity of tubes, a grid of micro-channels in this case, where a fluid flows, usually water. As it happens in every heat exchanger, the intake air charge flows within the grid giving up its waste heat to the fluid, cooling itself.

intercooler opened Ferrari

Rival teams of the Ferrari are supposing that the intercooler of the Ferrari could be employing oil to achieve the cooling of the intake air charge. The use of oil is not prohibited, unless it evaporates leading to a contamination of the intake air charge directed to the power unit. The insertion of oil in the combustion engine boosts the performances of the combustion process, a practice that has been forbidden by the FIA technical regulations.

intercooler Ferrari engine

Filling options in cooling towers

Chapter two in the cooling towers components saga. Let’s face the types of filling elements, which is the component within which happens the cooling of water. It is possibile to divide the typology of filling systems in two large families, film filling and splash filling. As the name itself tells, in film filling water flows along the walls of the filling pack creating a water film, increasing thermal exchange surface for direct thermal transfer between the flowing film water and the air rising up in countercurrent. Splash filling provide instead the spreading of the water flow distributed by nozzles in many droplets, increasing that way the direct air/water thermal exchange surface.

Materials: both systems are made of plastic materials. Film filling can be in PVC or polypropylene, splash filling is usually realized in form of polypropylene grids.

Efficiency comparison: film filling offers a higher thermal transfer efficiency, thus at equal water load and thermal capacity a splash tower solution will be bigger and more expensive than a film tower. Otherwise, in case of dirty water, containing polluting particles and filaments, a splash filling is preferable because it won’t clog, while a film filling can easily get clogged requiring periodical maintenance or even the substitution of the filling packs in order to restore the cooling efficiency of the evaporative tower. If the maintenance interventions happen within intervals of years, a film filling system can be an affordable solutions still, but in case of a very dirty fluid to be cooled that leads to cleaning or substitution within days or weeks, a splash filling solution is the only one possible.

Thermoregulation Atex skid package units

The thermoregulating units developed by Tempco for the temperature control in Atex environments are supplied as package skid units ensuring maximum flexibility, with remote management option and compete with certifications required for industrial environments with explosive atmosphere, tipically in pharma, chemical and oil & gas plants.

The engineering of equipments for this kind of environments, in presence of air gases, vapours, mists or dusts coming from the processed products, requires a series of precautions, from the selection of constructive materials Atex compliant through the evaluation of the temperature class.

Temperature classification defines in particular the maximum surface temperature that a machinery, both thermal or electrical, can reach when installed in explosion risk environments, that Tempco evaluates with maximum attention together with the final user. In depth, the temperature class impose that the maximum surface temperature must always be lower than the auto-ignition temperature of the flammable substances in the working environment. The Atex equipments employed can thus include an Atex thermostat for maximum temperature, an Atex pressure switch for maximum pressure check and an Atex temperature sensor.

skid Atex termoregolazione

Also the assembly of components of an Atex skid unit requires some peculiar care. The equipments are intended to thermoregulate fluids, often diathermic oil at high temperatures, so that is crucial to ensure the perfect seal of junction points, because leakage can become a critical issue in hazardous and explosive atmospheres. All the internal connections in the skid unit are flange joints and/or welded. All the gaskets on the flanges can employ spirometallic gaskets, while seals on the instruments, when welding is not possible, are metallic to avoid any possible leakage.

In addition, the flange connections are not only intended to avoid oil leaks, a very critical event in case of Atex environments, but also allow an easy installation. Flange connections provide indeed the guarantee of correct installment values, while with threaded connections one or two thread rotations are enough to get off quota, in addition to the risk of oil leaks. Finally, usually the construction material is stainless steel, in order to ensure maximum corrosion resistance in aggressive environments.