{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:15:16Z","timestamp":1760242516566,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2017,8,1]],"date-time":"2017-08-01T00:00:00Z","timestamp":1501545600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Tsinghua University Initiative Scientific Research Program","award":["20161080065"],"award-info":[{"award-number":["20161080065"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a highly sensitive flow-rate sensor with carbon nanotubes (CNTs) as sensing elements. The sensor uses micro-size centimeters long double-walled CNT (DWCNT) strands as hot-wires to sense fluid velocity. In the theoretical analysis, the sensitivity of the sensor is demonstrated to be positively related to the ratio of its surface. We assemble the flow sensor by suspending the DWCNT strand directly on two tungsten prongs and dripping a small amount of silver glue onto each contact between the DWCNT and the prongs. The DWCNT exhibits a positive TCR of 1980 ppm\/K. The self-heating effect on the DWCNT was observed while constant current was applied between the two prongs. This sensor can evidently respond to flow rate, and requires only several milliwatts to operate. We have, thus far, demonstrated that the CNT-based flow sensor has better sensitivity than the Pt-coated DWCNT sensor.<\/jats:p>","DOI":"10.3390\/s17081756","type":"journal-article","created":{"date-parts":[[2017,8,1]],"date-time":"2017-08-01T03:30:06Z","timestamp":1501558206000},"page":"1756","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Highly Sensitive Hot-Wire Anemometry Based on Macro-Sized Double-Walled Carbon Nanotube Strands"],"prefix":"10.3390","volume":"17","author":[{"given":"Dingqu","family":"Wang","sequence":"first","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China"},{"name":"Collaborative Innovation Center of Advanced Nuclear Energy Technology, Tsinghua University, Beijing 100084, China"},{"name":"Key Laboratory of Advanced Reactor Engineering and Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei","family":"Xiong","sequence":"additional","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhaoying","family":"Zhou","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rong","family":"Zhu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xing","family":"Yang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Precision Measurement Technology and Instrument, Department of Precision Instrument, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Weihua","family":"Li","sequence":"additional","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yueyuan","family":"Jiang","sequence":"additional","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yajun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,8,1]]},"reference":[{"key":"ref_1","unstructured":"Perry, A.E. (1982). Hot-wire filaments and simple models. Hot-Wire Anemometer, Oxford University Press. [1st ed.]."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Bruun, H.H. (1995). Basic Principles of hot-wire anemometry. Hot-Wire Anemometer Principles and Signal Analysis, Oxford University Press. [1st ed.].","DOI":"10.1093\/oso\/9780198563426.001.0001"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1115\/1.2175149","article-title":"Heat Conduction in Nanofluid Suspensions","volume":"128","author":"Vadasz","year":"2006","journal-title":"J. Heat Transf."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1299\/jtst.5.51","article-title":"Submicroscale Flow Sensor Employing Suspended Hot Film with Carbon Nanotube Fins","volume":"5","author":"Ito","year":"2010","journal-title":"J. Therm. Sci. Technol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2065","DOI":"10.1098\/rsta.2004.1430","article-title":"Electronic, Thermal and Mechanical Properties of Carbon Nanotubes","volume":"362","author":"Dresselhaus","year":"2004","journal-title":"Philos. Trans. R. Soc. A"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/j.synthmet.2015.09.014","article-title":"Mechanical Properties of suspended individual carbon nanotube studied by atomic force microscope","volume":"216","author":"Lee","year":"2016","journal-title":"Synth. Met."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/S0009-2614(02)01434-3","article-title":"Mechanical and electrical properties of carbon nanotube ribbons","volume":"365","author":"Li","year":"2002","journal-title":"Chem. Phys. Lett."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"072401","DOI":"10.1115\/1.4032955","article-title":"Measurement of Thermal and Electrical Properties of Multiwalled Carbon Nanotubes-Water Nanofluid","volume":"138","author":"Sahin","year":"2016","journal-title":"J. Heat Transf."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1109\/TNANO.2011.2118228","article-title":"A Picowatt Powered Carbon-Nanotube-Based Thermal Convective Motion Sensor","volume":"10","author":"Zhang","year":"2011","journal-title":"IEEE Trans. Nanotechnol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"161905","DOI":"10.1063\/1.4824757","article-title":"Evaluation of Thermal Conductivity of Single Carbon Nanotubes in Air and Liquid Using a Fluorescence Temperature Sensor","volume":"103","author":"Maruyama","year":"2013","journal-title":"Appl. Phys. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.sna.2013.04.038","article-title":"Carbon Nanotube Thermal Probe for Quantitative Temperature Sensing","volume":"199","author":"Hirotani","year":"2013","journal-title":"Sens. Actuators A"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"4898","DOI":"10.3390\/s100504898","article-title":"High Sensitivity Carbon Nanotubes Flow-Rate Sensors and Their Performance Improvement by Coating","volume":"10","author":"Yang","year":"2010","journal-title":"Sensors"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"095008","DOI":"10.1088\/0960-1317\/22\/9\/095008","article-title":"Characterization of a Silicon Nanowire-Based Cantilever Air-flow Sensor","volume":"22","author":"Zhang","year":"2012","journal-title":"J. Micromech. Microeng."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"15421","DOI":"10.1039\/C5NR03215F","article-title":"Suspended single-walled carbon nanotube fluidic sensors","volume":"7","author":"Son","year":"2015","journal-title":"Nanoscale"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1049\/iet-nbt.2013.0040","article-title":"Carbon nanotube-based hot-film and temperature sensor assembled by optically-induced dielectrophoresis","volume":"8","author":"Hsu","year":"2014","journal-title":"IET Nanobiotechnol."},{"key":"ref_16","unstructured":"Wong, V.T.S., and Li, W.J. (2003, January 22\u201323). Bulk Carbon Nanotubes as Sensing Element for Temperature and Anemometry Micro Sensing. Proceedings of the IEEE the Sixteenth Annual International Conference on Micro Electro Mechanical Systems, Kyoto, Japan."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"215401","DOI":"10.1088\/1361-6463\/aa6cd6","article-title":"Solvent-free fabrication of biodegradable hot-film flow sensor for noninvasive respiratory monitoring","volume":"50","author":"Dinh","year":"2017","journal-title":"J. Phys. D Appl. Phys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1447","DOI":"10.1126\/science.1101398","article-title":"Macroscopic, neat, single-walled carbon nanotube fibers","volume":"305","author":"Ericson","year":"2005","journal-title":"Science"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"8844","DOI":"10.1021\/jp049434x","article-title":"Large Scale Synthesis of Long Double-Walled Carbon Nanotubes","volume":"108","author":"Wei","year":"2004","journal-title":"J. Phys. Chem. B"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"064518","DOI":"10.1063\/1.3093680","article-title":"Multiwalled carbon nanotube films as small-sized temperature sensors","volume":"105","author":"Bartolomeo","year":"2009","journal-title":"J. Appl. Phys."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"06FD25","DOI":"10.1143\/JJAP.51.06FD25","article-title":"Temperature Dependent Resistance of Multi-Wall Carbon Nanotube","volume":"51","author":"Kawabe","year":"2012","journal-title":"Jpn. J. Appl. Phys."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"265503","DOI":"10.1088\/0957-4484\/22\/26\/265503","article-title":"A comparative study of 1\/f noise and temperature coefficient of resistance in multiwall and single-wall carbon nanotube bolometers","volume":"22","author":"Lu","year":"2011","journal-title":"Nanotechnology"},{"key":"ref_23","unstructured":"Fung, C.K.M., and Li, W.J. (2003, January 27\u201331). Ultra-Low-Power and High-Frequency-Response Carbon Nanotube Based MEMS Thermal Sensors. Proceedings of the 2003 IEEE\/RSJ International Conference on Intelligent Robots and Systems, Las Vegas, NV, USA."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"979","DOI":"10.1109\/JMEMS.2003.820261","article-title":"Development and characterization of surface micromachined, out-of-plane hot-wire anemometer","volume":"12","author":"Chen","year":"2003","journal-title":"J. Microelectromech. Syst."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/8\/1756\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T18:44:42Z","timestamp":1760208282000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/17\/8\/1756"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,8,1]]},"references-count":24,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2017,8]]}},"alternative-id":["s17081756"],"URL":"https:\/\/doi.org\/10.3390\/s17081756","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2017,8,1]]}}}