Laboratory of heat exchangers and condensers

The laboratory’s main activity is the experimental evaluation of heat transfer on heat exchange surfaces during heating/cooling of liquids and gases. We focus primarily on evaluating heat flows of non-standard geometric configurations of heat exchange surfaces (sprinkled exchangers, labyrinth seals, small channels) and on energy applications of heat exchangers with phase change of the working substance (boiling, condensation). The laboratory facilities of specialised laboratories are used for research activities, and thanks to the mobile apparatus, we also carry out measurements "in the field.".

The laboratory activities are professionally based on a diverse range of previously implemented activities of the Department of Power Engineering. This is mainly the area of evaluation of heat transfer in partial components of energy equipment, connected mainly with the development of absorption units and steam condensers. The trends monitored by the laboratory are the area of thermal energy recovery, increasing the efficiency of energy equipment by lowering the temperature of the exhaust gases and and condensation of water vapor in the flue gas, as well as by reducing the heat removal temperature of the steam circuits. In this area, basic and applied research is currently focused primarily on the condensation of steam and steam-gas mixtures. To this end, the research facilities have been set up. These enable:

  • to observe the behaviour of the condensate film in the pipeline (character and speed)
  • to experimentally verify the heat transfer coefficients on the outer and inner heat exchange surface of the pipeline (the surface can be smooth, grooved or hydrophobic)

The experimental activity uses inverse identification of heat fluxes from local temperature measurement, direct heat flux measurement, temperature monitoring of inaccessible surfaces using liquid crystals and thermal imaging technology, which has been successfully used for many years for diagnostics and predictive maintenance in mechanical engineering, electrical engineering, energy and construction industry. For these purposes, the Department of Power Engineering uses, in addition to several standard thermal imaging cameras, an infrared camera FLIR SC 660. FLIR camera SC (scientific) allows online recording of temperature field changes with a frequency of 30 Hz in a thermogram resolution of 640 × 420 pixels which ensures high-quality complex measurements in basic research when observing the temperature fields of the investigated equipment or processes and to perform measurements of thermal equipment in power plants or heating plants. The measured data are then analysed in the post-processing using specialised programs.

We offer

  • Experimental evaluation of heat fluxes in laboratory conditions or operations.
  • Design and construction solution of heat exchangers.
  • Numerical simulations of heat transfer and temperature fields.
  • Consultation of heat flux measurement methodology.

Equipment

The following devices are used for measurement and research:

  • National Instruments modular measuring and control system, including recording and control in LabVIEW.
  • Omega DAQ 56 data acquisition system, including LabVIEW recording.
  • Temperature sensors (thermocouples T, J, K, resistance probes PT100), pressure sensors, gas and liquid flow sensors, mass gas regulators.
  • Steam generator with steam/gas superheater (up to 40 kg/h and 700 °C).
  • FLIR SC660 thermal imaging camera.
  • Portaflow 330 ultrasonic flow meter.
  • Double-beam UV-VIS spectrophotometer Metash UV-9000.
  • XS Instruments OXY70 Oximeter.

More detailed information about these devices can be found in the list of equipment.

Selected implemented projects:

  • ComSi: Computer Simulations for Effective Low-emission Energy Engineering reg. no.: CZ.02.1.01/0.0/0.0/16_026/0008392 financed from OP VVV, realised: 2018 – 2022
  • Risk analysis of the block heat exchanger station Temelín NPP, 2021, 2021
  • BioCCS: Research centre for low-carbon energy technologies reg. no.: CZ.02.1.01/0.0/0.0/16_019/0000753 financed from OP VVV, realised: 2018 – 2022
  • NETME Centre - New technologies for mechanical engineering (ED0002/01/01) and NETME CENTRE PLUS (LO1202)
  • The Czech Science Foundation 101/10/1669: Falling film heat transfer on horizontal tubes in a low-pressure atmosphere

Selected publications and results:

  • TOMAN, F.; KRACÍK, P.; POSPÍŠIL, J. Heat transfer during condensation of water vapour in the presence of non-condensable gas in vertical tube of small diameter. Case Studies in Thermal Engineering, 2022, roč. 40, č. 12, s. 1-15. ISSN: 2214-157X.
  • KRACÍK, P.; TOMAN, F.; POSPÍŠIL, J.; KRAML, S. A Heat Exchanger with Water Vapor Condensation on the External Surface of a Vertical Pipe. ENERGIES, 2022, roč. 15, č. 15, s. 1-16. ISSN: 1996-1073.
  • TOMAN, F.; KRACÍK, P.; POSPÍŠIL, J. Influence of tube diameter and steam flow rate on heat transfer in a vertical pipe of condenser: experimental investigation of copper pipes. Chemical Engineering Transactions, 2021, roč. 88, č. 2021, s. 601-606. ISSN: 2283-9216.
  • TOMAN, F.; KRACÍK, P.; POSPÍŠIL, J.; ŠPILÁČEK, M. Comparison of water vapour condensation in vertically oriented pipes of condensers with internal and external heat rejection. Energy, 2020, roč. 208, č. 118388, s. 1-11. ISSN: 0360-5442.
  • KLIMEŠ, L.; POSPÍŠIL, J.; ŠTĚTINA, J.; KRACÍK, P. Semi-empirical balance-based computational model of air-cooled condensers with the A-frame layout. Energy, 2019, roč. 182, č. 1, s. 1013-1027. ISSN: 0360-5442.
  • KRACÍK, P.; BALÁŠ, M.; LISÝ, M.; POSPÍŠIL, J. Experimental Verification of Impact of Sprinkled Area Length on Heat Exchange Coefficient. Advances in Materials Science and Engineering, 2019, roč. 2019, č. 1, s. 1-7. ISSN: 1687-8434.
  • POSPÍŠIL, J.; KRACÍK, P.; ŠTĚTINA, J.; KLIMEŠ, L. Air Cooled Condenser Model, Summary Research Report,, 2016.
  • KRACÍK, P.; POSPÍŠIL, J. Influence of Underpressure on Heat Transfer And Temperature Field at Sprinkled Tube Bundle. Applied Mechanics and Materials, 2016, č. 832, s. 200-206. ISSN: 1662-7482.
  • KRACÍK, P.; BALÁŠ, M.; LISÝ, M.; POSPÍŠIL, J. Effect of size sprinkled heat exchange surface on developing boiling. Advances in Mechanical Engineering, 2016, roč. 8, č. 6, s. 1-7. ISSN: 1687-8132.
  • TOMAN, F.; KRACÍK, P.; POSPÍŠIL, J.: A pressure device for evaluating the effects on the flow of a liquid film on the inner wall of a pipe. Fakulta strojního inženýrství, VUT v Brně, Technická 2896/2, 616 69 Brno, Budova C3/314 (funkční vzorek).
  • POSPÍŠIL, J.; KRACÍK, P.; ŠNAJDÁREK, L.: Vacuum test chamber for evaluation of heat transfer on sprinkler tube bundles in deep vacuum. Fakulta strojního inženýrství VUT, Technická 2896/2, 616 69 Brno, Budova C3/213 (funkční vzorek).

Selected Master’s and Bachelor’s theses

We also involve Bachelor’s and Master’s degree students in the implementation of research and development activities, as the laboratory equipment enables them to acquire a whole range of practical knowledge that can be used when working on the final thesis.

  • JURÁŠ, F. Kondenzátor páry. Brno: Vysoké učení technické v Brně, Fakulta strojního inženýrství, 2017. 76 s. Vedoucí diplomové práce doc. Ing. Jiří Pospíšil, Ph.D.
  • BOCHNÍČEK, O. Vzduchem chlazený kondenzátor. Brno: Vysoké učení technické v Brně, Fakulta strojního inženýrství, 2017. 110 s. Vedoucí diplomové práce doc. Ing. Jiří Pospíšil, Ph.D.
  • KLODA, M. Vzduchem chlazený kondenzátor. Brno: Vysoké učení technické v Brně, Fakulta strojního inženýrství, 2015. 75 s. Vedoucí diplomové práce doc. Ing. Jiří Pospíšil, Ph.D.
  • COPEK, T. Přestup tepla na skrápěném trubkovém svazku. Brno: Vysoké učení technické v Brně, Fakulta strojního inženýrství, 2014. 38 s. Vedoucí bakalářské práce Ing. Petr Kracík.
  • ZACHAR, M. Termovizní měření. Brno: Vysoké učení technické v Brně, Fakulta strojního inženýrství, 2014. 42 s. Vedoucí bakalářské práce Ing. Petr Kracík.

Kontakt

Ing. Petr Kracík, Ph.D.
Energy Institute, FME BUT
e-mail: kracik@fme.vutbr.cz
tel.: +420 541 142 585

About us