Come calcolare il numero di Graetz (Gz) rapporto adimensionale fondamentale termofluidodinamica che misura il trasferimento convettivo di calore rispetto alla conduzione termica nella regione di entrata termica per flusso laminare in tubi: Gz = (D/L) * Re * Pr. D diametro tubo m; L lunghezza tubo m; Re Reynolds = rho*v*D/mu; Pr Prandtl = mu*cp/k = nu/alpha. Equivalente Gz = (m_dot * cp) / (k * L) dove m_dot portata massa kg/s.

Inverse Graetz: 1/Gz = L/(D*Re*Pr) = (alpha*L)/(D^2*v) + dimensionless thermal axial coordinate.

Classificazione regime: Gz<1 fully developed thermal boundary layer reached + lunghi tubi + Nu=3.66 constant T_w boundary + Nu=4.36 constant heat flux + thermal entry length passed; 1<Gz<10 transition thermal entry developing + intermediate behavior; 10<Gz<100 thermal entry short tube + boundary layer developing + Hausen correlation; Gz>100 strong entry very short tube + thin boundary layer + Leveque solution Nu = 1.077*Gz^(1/3) + asymptotic high heat transfer.

Hausen correlation laminar entrance constant T_w: Nu_D = 3.66 + (0.0668 * Gz)/(1 + 0.04 * Gz^(2/3)) + valid Re0.5 + isothermal wall.

Sieder-Tate correlation: Nu_D = 1.86 * (Re*Pr*D/L)^(1/3) * (mu_b/mu_w)^0.14 + viscosity correction wall + valid 0.48<Pr10.

Leveque solution: Nu = 1.077 * Gz^(1/3) + thin boundary layer + parabolic velocity profile + asymptotic short entry.

Thermal entry length: L_t/D = 0.05 * Re * Pr for laminar pipe + thermally developing region; L_t/D = 10 turbulent + much shorter entry.

Numeri correlati: Reynolds Re = rho*v*D/mu; Prandtl Pr = mu*cp/k (aria 0.71; acqua 7; oli 100-1000; mercurio 0.025); Nusselt Nu = h*D/k; Stanton St = Nu/(Re*Pr); Peclet Pe = Re*Pr.

Boundary conditions: constant wall temperature T_w Nu_inf = 3.66 + biological dialysis hot water HVAC; constant heat flux q_w Nu_inf = 4.36 + electric heating + nuclear; uniform inlet temperature T_in + thermally developing.

Configurazioni geometriche: round tube classic Gz analysis; concentric annulus + Krasik-Tobilevich + Lewis Graetz; rectangular channel + microchannel + Goldsmith-Mertz; parallel plates + asymptotic Nu=7.54 const T_w; helical coil + Dean number coupling + secondary flow. Storia: Leo Graetz (Breslau Silesia Prussia 1856 - Munich Germany 1941) Universitat Strassburg Vorlesung + Universitat Munchen 1893 Professor + 1882-1941 academic career; 1885 paper Annalen Physik 25:337 'Uber die Warmeleitungsfahigkeit von Flussigkeiten' classic Graetz problem laminar pipe heat transfer + 1882 paper Annalen Physik 18:79 + 1883 paper viscosity + Graetz problem analysis classical solution + Graetz number eponym + thermal entry developing problem; 1900 textbook 'Lehrbuch der Theoretischen Physik' Munich Habilitation + 1922 textbook 'Die Atomtheorie' Munich; pioneer thermal physics + viscosity measurements + Graetz problem laminar heat transfer pipe entry classical analytical solution + eigenvalue series Graetz solution.

Wilhelm Lewis Nusselt (Nuremberg Germany 1882 - Munich 1957) TH Munchen 1907 + TH Karlsruhe 1925 + Munchen 1925-1957 chair; 1916 paper VDI Z 60:541 'Die Oberflachenkondensation des Wasserdampfes' classic film condensation + Nusselt number eponym + 1910 thesis 'Warmeubergang' + Habilitation TH Munchen + Nu = h*L/k + dimensional analysis heat transfer; 1925 paper Z VDI 69:1 'Das Grundgesetz des Warmeuberganges'.

Eduard Schmidt (Vohwinkel Germany 1892 - Karlsruhe 1975) TH Karlsruhe + TH Munchen 1937-1962; 1929 paper Beih Gesundh Ing 1:1 'Warmeubergang in Rohrleitungen' + Schmidt mass transfer analogy + Sc = nu/D + Schmidt number eponym + 1936 textbook 'Einfuhrung in die Technische Thermodynamik' classic German textbook + 1953 'Properties of Water and Steam in SI Units'; pioneer thermal engineering + heat-mass transfer analogy.

Heinz Hausen (Brunswick Germany 1896 - Karlsruhe 1981) TH Hannover + TH Karlsruhe + TH Munchen 1949-1968; 1959 'Neue Gleichungen fur die Warmeubertragung bei freier oder erzwungener Stromung' + Hausen correlation Nu_D laminar entrance + Nu = 3.66 + (0.0668*Gz)/(1+0.04*Gz^(2/3)) + 1958 textbook 'Warmeubertragung im Gegenstrom Gleichstrom und Kreuzstrom' classic.

Eugene Sieder + Charles Tate USA Sun Oil Co 1936; 1936 paper Ind Eng Chem 28:1429 'Heat transfer and pressure drop of liquids in tubes' classic Sieder-Tate correlation laminar/turbulent + viscosity correction + petroleum heating.

Joseph Boussinesq France 1903 + Andre Leveque France 1928; Leveque 1928 paper Ann Mines Mem 13:201 'Les lois de la transmission de chaleur par convection' classic Leveque solution thermal entry + Nu = 1.077 * Gz^(1/3) thin boundary layer asymptotic + Pohlhausen integral method. Eredita: Bird-Stewart-Lightfoot 'Transport Phenomena' 2nd ed 2007 Wiley 905 pages + Welty-Wilson-Wicks-Rorrer 'Fundamentals' 6th ed 2014 + Bejan 'Convection Heat Transfer' 4th ed 2013 Wiley 658 pages classic + Incropera-DeWitt-Bergman-Lavine 'Fundamentals of Heat and Mass Transfer' 8th ed 2018 Wiley 1080 pages classic; Shah-London 'Laminar Flow Forced Convection in Ducts' 1978 Academic Press 477 pages classic monograph.

Italia ricerca Graetz + heat transfer + scambiatori + microcanali: CNR-ITAE Istituto Tecnologie Avanzate Energia Messina 200 + idrogeno + fuel cells + heat exchangers; CNR-ICMATE Istituto Chimica Materia Condensata Tecnologie Energetiche Genova + Padova + Lecco 200 + microcanale heat transfer; CNR-IPCB Pozzuoli + Lecco + Catania 250 + polymer microchannel; CNR-ISTI Pisa 250 CFD computational fluid dynamics; CNR-IIT Italian Institute Technology Genova Morego 1700 + microfluidics + lab-on-chip + bio-inks; ENEA Casaccia + Frascati + Brindisi + Trisaia + 11 centri 2700 + thermal storage + cooling + heat exchangers; RSE Milano 1000 + thermal storage + heat exchangers; SOGIN Roma 1100 + nuclear cooling; OGS Trieste 250; CMCC Lecce 200.

Italia università Graetz + heat transfer + microcanali: Politecnico Milano DEIB + DENG + LCM 7500 + Carlo Cercignani Boltzmann legacy + Renzo Piazza CFD + Marco Mauri thermal storage + Cesare Maria Joppolo HVAC + Luca Molinaroli psychrometric + Alfonso Niro heat transfer + Marco Marengo microchannel; Politecnico Torino DENERG + DIATI 5000 + Marco Carlo Masoero buildings + Marco Filippi indoor + Marco Simonetti psychrometric + Eliodoro Chiavazzo nanofluid heat transfer; Federico II Napoli DICMaPI + DII + DIETI 5000 + Vincenzo Russo unit operations + Maria Chiara Mosca + Antonio Apicella; Bologna DICAM + DEI + DIN 4000 + DICAM Termofluidodinamica + Pier Luigi Dragoni HVAC + Cesare Saccani thermal storage + Vincenzo Bianco heat transfer; Padova DII + DEI + ICEA 3000 + CISAS + Renato Lazzarin HVAC + Marco Noro heat pumps + Massimo Brunetti drying + Gianluca Roto heat exchangers; Pisa DICI + DESTeC 2500 + Walter Grassi heat transfer + Daniele Testi heat pumps + Andrea Lucchini drying; Politecnico Bari DEI 2500; Sapienza Roma DICEA + DIMA + DIET 4000 + Livio De Santoli energy + Marco Cecconi HVAC; Genova DICCA + DIBRIS 2000 + IIT 1700; Trento DICAM 1962; Salerno DIIN 1968; Firenze DIEF 1321; Cagliari DIMCM 1606.

Italia industria HVAC + scambiatori calore + heat exchangers: Daikin Italia Milano 500 + chiller + heat exchangers; Mitsubishi Electric Italia Milano 400 + heat exchangers Ecodan; Carrier Italia Roma 300 + chillers heat exchangers; Climaveneta Bassano del Grappa VI 800 + chillers + heat exchangers commercial industrial; Aermec Bevilacqua VR 1962 1100 + chillers + heat pumps + heat exchangers; Galletti SpA Bentivoglio BO 1928 600 + fan-coil + AHU + heat exchangers; Sabiana SpA Corbetta MI 1929 700 + radiators + heat exchangers; Riello SpA Legnago Verona 1922 1500 + caldaie heat exchangers; Ariston Group Fabriano AN 1930 7000 + boilers + heat exchangers; Beretta Caldaie Lecco 700; Ferroli Verona 2000; Immergas Brescello RE 1500; De Longhi Treviso 8000.

Italia industria scambiatori calore industriali + petrochemical: Eni SpA Roma 32000 + raffinerie 5 sites + heat exchangers; Saipem Milano 32000 oil&gas EPC + heat exchangers shell-and-tube; Tecnimont Milano 6000 EPC + heat exchangers process; Snam Milano 6000; Italgas Torino 4000; Ansaldo Energia Genova 4000 + condensers heat exchangers turbines; Walter Tosto SpA Chieti 1960 1500 + pressure vessels heat exchangers + Solar Tower Receiver Crescent Dunes; Brembana&Rolle Costa Volpino BG 1968 700 + heat exchangers; Eumetal Vimercate MB 200; Pielleitalia Schio VI 1968 200 + heat exchangers + welded plate; Costacurta SpA Milano 1921 250 + heat exchangers + filtration.

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Formula numero Graetz

Definizione: Gz = (D/L) * Re * Pr. Equivalente Gz = m_dot*cp/(k*L).

Inverse Graetz: 1/Gz = (alpha*L)/(D^2*v) + dimensionless thermal axial coordinate.

Hausen correlation T_w costante: Nu_D = 3.66 + (0.0668*Gz)/(1+0.04*Gz^(2/3)) + Re0.5.

Sieder-Tate correlation: Nu_D = 1.86*(Re*Pr*D/L)^(1/3)*(mu_b/mu_w)^0.14 + viscosity correction wall.

Leveque thin BL: Nu = 1.077*Gz^(1/3) + asymptotic short entry.

Thermal entry length: L_t/D = 0.05*Re*Pr laminar; L_t/D=10 turbulent.

Storia e contesto

Leo Graetz (Breslau Silesia Prussia 1856 - Munich Germany 1941) Universitat Strassburg Vorlesung + Universitat Munchen 1893 Professor + 1882-1941 academic career; 1885 paper Annalen Physik 25:337 'Uber die Warmeleitungsfahigkeit von Flussigkeiten' classic Graetz problem laminar pipe heat transfer + 1882 Annalen Physik 18:79 + 1883 viscosity + Graetz problem analytical solution + Graetz number eponym + thermal entry developing problem + eigenvalue series Graetz solution; 1900 textbook 'Lehrbuch der Theoretischen Physik' Munich + 1922 textbook 'Die Atomtheorie' Munich; pioneer thermal physics + viscosity measurements + Graetz problem laminar heat transfer pipe entry classical analytical eigenvalue series solution.

Wilhelm Nusselt (Nuremberg Germany 1882 - Munich 1957) TH Munchen 1907 + TH Karlsruhe 1925 + TH Munchen 1925-1957 chair thermodynamics; 1916 paper VDI Z 60:541 'Die Oberflachenkondensation des Wasserdampfes' classic film condensation + Nusselt number eponym + 1910 thesis 'Warmeubergang' + Nu = h*L/k + dimensional analysis; 1925 paper Z VDI 69:1 'Das Grundgesetz des Warmeuberganges' classic.

Eduard Schmidt (Vohwinkel Germany 1892 - Karlsruhe 1975) TH Karlsruhe + TH Munchen 1937-1962 chair; 1929 paper Beih Gesundh Ing 1:1 'Warmeubergang in Rohrleitungen' + Schmidt mass transfer analogy + Sc = nu/D + Schmidt number eponym + 1936 textbook 'Einfuhrung in die Technische Thermodynamik' classic German textbook + 1953 'Properties of Water and Steam in SI Units' classic.

Heinz Hausen (Brunswick Germany 1896 - Karlsruhe 1981) TH Hannover + TH Karlsruhe + TH Munchen 1949-1968 chair; 1959 'Neue Gleichungen fur die Warmeubertragung bei freier oder erzwungener Stromung' + Hausen correlation Nu_D laminar entrance + Nu = 3.66 + (0.0668*Gz)/(1+0.04*Gz^(2/3)) + 1958 textbook 'Warmeubertragung im Gegenstrom Gleichstrom und Kreuzstrom' classic 600 pages.

Eugene Sieder + Charles Tate USA Sun Oil Co Marcus Hook PA refinery 1936; 1936 paper Ind Eng Chem 28:1429 'Heat transfer and pressure drop of liquids in tubes' classic Sieder-Tate correlation laminar + turbulent + viscosity correction wall + petroleum oils heating + Marcus Hook refinery experiments.

Joseph Antoine Andre Leveque (France 1885-1932) Ecole Centrale Paris; 1928 paper Annales Mines 13:201 'Les lois de la transmission de chaleur par convection' classic Leveque solution thermal entry + Nu = 1.077*Gz^(1/3) thin boundary layer asymptotic + Pohlhausen integral method + Leveque approximation thermal boundary layer analytical solution. Eredita: Bird-Stewart-Lightfoot 'Transport Phenomena' 2nd ed 2007 Wiley 905 pages classic chemical engineering + Welty-Wilson-Wicks-Rorrer 'Fundamentals of Momentum Heat Mass Transfer' 6th ed 2014 + Bejan 'Convection Heat Transfer' 4th ed 2013 Wiley 658 pages classic + Incropera-DeWitt-Bergman-Lavine 'Fundamentals of Heat and Mass Transfer' 8th ed 2018 Wiley 1080 pages classic textbook + Shah-London 'Laminar Flow Forced Convection in Ducts' 1978 Academic Press 477 pages classic monograph + Kays-Crawford 'Convective Heat and Mass Transfer' 4th ed 2005 McGraw-Hill 558 pages classic.

Italia ricerca Graetz + heat transfer + scambiatori + microcanali + dialisi: CNR-ITAE Istituto Tecnologie Avanzate Energia Messina 200 + idrogeno + fuel cells + heat exchangers; CNR-ICMATE Istituto Chimica Materia Condensata Tecnologie Energetiche Genova + Padova + Lecco 200 + microcanale heat transfer; CNR-IPCB Pozzuoli + Lecco + Catania 250 + polymer microchannel; CNR-ISTI Pisa 250 CFD computational fluid dynamics; CNR-IIT Italian Institute Technology Genova Morego 1700 + microfluidics + lab-on-chip + bio-inks 3D bioprinting; ENEA Casaccia + Frascati + Brindisi + Trisaia + 11 centri 2700 + thermal storage + cooling + heat exchangers + ALFRED LFR Lead-cooled Fast Reactor; RSE Ricerca Sistema Energetico Milano 1000 + thermal storage + heat exchangers + smart grid; SOGIN Roma 1100 + nuclear cooling tower; OGS Trieste 250; CMCC Lecce 200.

Italia università Graetz + heat transfer + microcanali + dialisi: Politecnico Milano DEIB + DENG + LCM 7500 + Carlo Cercignani Boltzmann legacy + Renzo Piazza CFD + Marco Mauri thermal storage + Cesare Maria Joppolo HVAC + Luca Molinaroli psychrometric + Alfonso Niro heat transfer turbolenti + Marco Marengo microchannel boiling heat transfer world-leading; Politecnico Torino DENERG + DIATI 5000 + Marco Carlo Masoero buildings + Marco Filippi indoor + Marco Simonetti psychrometric + Eliodoro Chiavazzo nanofluid heat transfer + multiscale + Pietro Asinari Boltzmann; Federico II Napoli DICMaPI + DII + DIETI 1224 5000 + Vincenzo Russo unit operations + Maria Chiara Mosca + Antonio Apicella + Ciro Aprea HVAC; Bologna DICAM + DEI + DIN 1088 4000 + DICAM Termofluidodinamica + Pier Luigi Dragoni HVAC + Cesare Saccani thermal storage + Vincenzo Bianco heat transfer Genova; Padova DII + DEI + ICEA 1222 3000 + CISAS + Renato Lazzarin HVAC + Marco Noro heat pumps + Massimo Brunetti drying + Gianluca Roto heat exchangers + Davide Del Col scambiatori condensazione boiling; Pisa DICI + DESTeC 1343 2500 + Walter Grassi heat transfer + Daniele Testi heat pumps + Andrea Lucchini drying; Politecnico Bari DEI 1990 2500;

Sapienza Roma DICEA + DIMA + DIET 1303 4000 + Livio De Santoli energy + Marco Cecconi HVAC; Genova DICCA + DIBRIS 1481 2000 + IIT 1700 Vincenzo Bianco heat transfer; Trento DICAM 1962; Salerno DIIN 1968; Firenze DIEF 1321; Cagliari DIMCM 1606.

Italia industria scambiatori calore industriali + petrochemical + power: Eni SpA Roma 1953 32000 + raffinerie 5 sites Sannazzaro Livorno Taranto Gela Sarroch + heat exchangers shell-and-tube + Versalis polimeri; Saipem Milano 1957 32000 oil&gas EPC + heat exchangers shell-and-tube; Tecnimont Milano Maire Tecnimont 6000 EPC + heat exchangers process + ammonia methanol; Snam Milano 1941 6000; Italgas Torino 4000; Ansaldo Energia Genova 1853 4000 + condensers heat exchangers turbines GT26 GT36; Walter Tosto SpA Chieti 1960 1500 + pressure vessels + heat exchangers + Solar Tower Receiver Crescent Dunes Solar Reserve Tonopah NV; Brembana&Rolle Costa Volpino BG 1968 700 + heat exchangers shell-and-tube; Eumetal Vimercate MB 200 + heat exchangers; Pielleitalia Schio VI 1968 200 + heat exchangers + welded plate world-leading; Costacurta SpA Milano 1921 250; SACMI Imola BO 1919 4000 + ceramic heat exchangers; HRS Heat Exchangers Italian 200.

Italia industria HVAC + scambiatori chiller + heat exchangers + condizionamento: Daikin Italia Milano 500 + chillers + heat exchangers; Mitsubishi Electric Italia 400 + heat exchangers Ecodan; Carrier Italia Roma 300; Climaveneta + Mitsubishi Electric Hydronics Italy Bassano del Grappa VI 800 chillers + heat pumps grandi taglie commercial + heat exchangers; Aermec Bevilacqua VR 1962 1100 + chillers + heat pumps + heat exchangers; Galletti SpA Bentivoglio BO 1928 600 + fan-coil + AHU + heat exchangers; Sabiana SpA Corbetta MI 1929 700 + radiators + heat exchangers; Riello SpA Legnago Verona 1922 1500 + caldaie a condensazione + heat exchangers + heat pumps; Ariston Group Fabriano AN 1930 7000 + boilers + water heaters + heat exchangers + heat pumps + Atag Cuenod ELCO; Beretta Caldaie Lecco 700; Ferroli Verona 1955 2000 + caldaie heat exchangers; Immergas Brescello RE 1500; De Longhi Treviso 1902 8000 + heaters; Olimpia Splendid Cellatica BS 1956 700; Argo + Gree + Hisense Italy 300.

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Tabella valori Graetz

• Gz = (D/L)*Re*Pr: definizione
• Gz = m_dot*cp/(k*L): equivalente
• 1/Gz = (alpha*L)/(D^2*v): thermal axial
• Gz<1 fully developed: Nu=3.66 const Tw
• 1<Gz<10 transition
• 10<Gz<100 thermal entry: Hausen
• Gz>100 strong entry: Leveque thin BL
• Hausen Nu = 3.66 + (0.0668*Gz)/(1+0.04*Gz^(2/3))
• Sieder-Tate Nu = 1.86*(Re*Pr*D/L)^(1/3)*(mu_b/mu_w)^0.14
• Leveque Nu = 1.077*Gz^(1/3): asymptotic
• Nu=4.36 const heat flux
• L_t/D = 0.05*Re*Pr: thermal entry length laminar
• L_t/D = 10: turbulent
• Pr aria 0.71 acqua 7
• Mercurio Pr=0.025
• Oli Pr=100-1000
• Graetz Germany 1885: Annalen Physik 25:337
• Nusselt 1916 1925
• Schmidt 1929
• Hausen 1959: correlation
• Sieder-Tate 1936: viscosity correction
• Leveque 1928: thin BL Nu=1.077*Gz^(1/3)
• Italia Eni 32000: scambiatori
• Italia Walter Tosto 1500: pressure vessels
• Italia Daikin 500 + Climaveneta 800: HVAC
• Italia Mirandola 50 companies: dialysis 50% world
• Italia Fresenius Medical Care 1500: dialyzers
• Italia Politecnico Milano LCM 7500: Marengo microchannel
• Italia IIT Genova 1700: microfluidics
• Italia ENEA Brasimone 200: ALFRED LFR

Esempi numerici dettagliati

Esempio 1 - Tubo lungo dialisi developed. D=10 mm, L=10 m, Re=100, Pr=5. Gz = (0.01/10)*100*5 = 0.5. Fully developed + Nu=3.66. Italia: Fresenius Medical Care 1500 + Mirandola district 50% world.

Esempio 2 - Compact heat exchanger. D=5 mm, L=0.5 m, Re=500, Pr=7. Gz = (0.005/0.5)*500*7 = 35. Thermal entry developing + Hausen Nu~6. Italia: Climaveneta 800 + Aermec 1100 + Galletti 600 + Walter Tosto 1500.

Esempio 3 - Microchannel cooling. D=100 micron, L=50 mm, Re=50, Pr=5. Gz = (1e-4/0.05)*50*5 = 0.5. Fully developed Nu=3.66. Italia: IIT Genova 1700 + STMicroelectronics 50000 + FBK Trento 2000 microchannel.

Esempio 4 - Dialysis hollow fiber. D=200 micron, L=20 cm, Re=30, Pr=7. Gz = (2e-4/0.2)*30*7 = 0.21. Fully developed dialyzer + Nu~3.66 const Tw + uremic toxin removal. Italia: Fresenius Medical Care Cremona Crema 1500 + Bellco Mirandola 600.

Esempio 5 - Short entry tube. D=25 mm, L=10 cm, Re=2000, Pr=7. Gz = (0.025/0.1)*2000*7 = 3500. Strong entry + Leveque Nu = 1.077*3500^(1/3) ~16. Italia: Saipem 32000 + Eni 32000 + Tecnimont 6000 + Ansaldo Energia 4000 process heat exchangers.

Limiti e considerazioni

1. Laminar assumption: Re<2300 + transition turbulent + Dittus-Boelter different.
2. Constant properties: real Pr(T) variable + viscosity Sieder-Tate correction.
3. Constant wall temperature vs heat flux: Nu_inf 3.66 vs 4.36 different.
4. Thermal entry: hydrodynamically developed assumption simultaneous developing different Kays-Crawford.
5. Compressibility: high speed gas + dissipation viscous Brinkman.
6. Buoyancy: mixed convection Ra/Re^2 + Gr/Re^2 + secondary flow.
7. Variable cross-section: tapered + helical Dean.
8. Surface roughness: enhanced laminar + transition.
9. Slip flow microchannel: Knudsen Kn>0.001 + rarefied gas.
10. Non-Newtonian: power-law + Herschel-Bulkley + Bingham + Carreau.

Errori comuni

Confondere Gz e Pe: Gz=(D/L)*Pe; Pe=Re*Pr.

Constant wall T vs heat flux: Nu_inf 3.66 vs 4.36 differenti boundary.

Hausen vs Sieder-Tate vs Leveque: range Gz appropriato + viscosity correction wall.

Thermal entry length: L_t/D=0.05*Re*Pr laminar; turbolento L_t/D=10.

Hydrodynamic vs thermal entry: simultaneous developing diverso da hydrodynamically developed.

Applicazioni pratiche

1. Scambiatori calore industriali: Italia Eni 32000 + Saipem 32000 + Tecnimont 6000 + Ansaldo Energia 4000 + Walter Tosto 1500 + Brembana&Rolle 700 + Pielleitalia 200 + SACMI 4000.
2. HVAC chiller heat exchangers: Italia Daikin 500 + Mitsubishi 400 + Carrier 300 + Climaveneta 800 + Aermec 1100 + Galletti 600 + Sabiana 700 + Riello 1500 + Ariston 7000.
3. Caldaie domestiche heat exchangers: Italia Riello 1500 + Beretta 700 + Ferroli 2000 + Immergas 1500 + Vaillant Saunier Duval Italia 300.
4. Microcanali microfluidica lab-on-chip: Italia IIT Genova 1700 + Politecnico Milano LCM 7500 Frangi MEMS Marengo microchannel + STMicroelectronics 50000 + FBK Trento 2000 + Brescia Poesio.
5. Dialisi emodialisi hollow fiber: Italia Fresenius Medical Care Cremona Crema 1500 + Baxter Roma 800 + Bellco Mirandola 600 + Sorin LivaNova 4500 + BD 800 + Eurosets 250 + Mirandola biomedical district 50 companies + 50% world heart-lung machines.
6. Medical hyperthermia: Italia LivaNova heater-cooler 3T + ospedali oncologia + IRCCS Istituti Ricovero e Cura Carattere Scientifico Italia 50.
7. Nuclear cooling heat exchangers ALFRED LFR: Italia SOGIN 1100 + Ansaldo Nucleare 800 + Newcleo Torino 200 + ENEA Brasimone 200 + ALFRED LFR Lead-cooled Fast Reactor demo Romania.
8. Solar thermal CSP heat exchangers: Italia Walter Tosto Chieti 1500 + Crescent Dunes SolarReserve + Archimede Solar Massa Martana 50 + Enel Green Power 1300.
9. Cogenerazione biomass heat exchangers: Italia Enel 65000 + Eni Plenitude 1500 + Falck Renewables 1500 + ERG 5000 + A2A 12000 + Hera 9000 + Iren 7800.
10. Universita ricerca scambiatori microcanali: Politecnico Milano DENG Marengo Niro Joppolo + Politecnico Torino DENERG Chiavazzo Asinari + Bologna DICAM Bianco + Padova DII Lazzarin Roto Del Col + Pisa DICI Grassi Testi + Genova IIT Athanassiou + Brescia Poesio.

Aggiornato a luglio 2026