Journal Articles
Morris, N, Rahmani, R, Rahnejat, H, Bhushan, B (2024)
Air foil thrust and journal bearing coatings: A review,
Journal of Tribology, 147(1), 010801, ISSN: 0742-4787. DOI:
10.1115/1.4065986.
Simpson, M, Rahmani, R, Dolatabadi, N,
Morris, N, Jones, D, Craig, C (2024)
An analytical friction model for point contacts subject to boundary and mixed elastohydrodynamic lubrication,
Tribology International, 196, 109699, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2024.109699.
Tomlinson, K, Davison, S, King, P, Howell-Smith, S, Slatter, T,
Morris, N (2024)
On the role of friction modifier additives in the oil control ring and piston liner contact,
Journal of Tribology, 146(4), 042201, ISSN: 0742-4787. DOI:
10.1115/1.4064302.
Nomikos, P, Rahmani, R,
Morris, N, Rahnejat, H (2023)
Measurement and prediction of thermal performance of automotive transmission radial lip seals,
Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, ISSN: 0954-4070. DOI:
10.1177/09544070231213903.
Bleger, A, Leighton, M,
Morris, N (2023)
Automotive e-motor bearing electrical discharge phenomena: An experimental and numerical investigation,
Tribology International, 191(2024), 109140, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2023.109140.
Humphrey, E, Elisaus, V, Rahmani, R, Mohammad Pour, M, Theodossiades, S,
Morris, N (2023)
Diamond Like-Carbon Coatings for Electric Vehicle Transmission Efficiency,
Tribology International, pp.108916-108916, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2023.108916.
Simpson, M, Dolatabadi, N, Rahmani, R,
Morris, N, Jones, D, Craig, C (2023)
Multibody dynamics of cross groove constant velocity ball joints for high performance racing applications,
Mechanism and Machine Theory, 188, 105407, ISSN: 0094-114X. DOI:
10.1016/j.mechmachtheory.2023.105407.
Simpson, M, Dolatabadi, N,
Morris, N, Rahmani, R, Jones, D, Christopher, C (2022)
Analysis of a cross groove constant velocity joint mechanism designed for high performance racing conditions,
Proceedings of the Institution of Mechanical Engineers Part K: Journal of Multi-Body Dynamics, 237(1), pp.16-33, ISSN: 1464-4193. DOI:
10.1177/14644193221129149.
Nomikos, P, Rahmani, R,
Morris, N, Rahnejat, H (2022)
An investigation of oil leakage from automotive driveshaft radial lip seals,
Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 237(13), pp.3108-3124, ISSN: 0954-4070. DOI:
10.1177/09544070221127105.
Morris, SA, Leighton, M,
Morris, N (2022)
Electrical field strength in rough infinite line contact elastohydrodynamic conjunctions,
Lubricants, 10(5), 87, DOI:
10.3390/lubricants10050087.
Morris, S,
Morris, N, Leighton, M (2022)
A time efficient thermal and hydrodynamic model for multi disc wet clutches,
SAE Technical Papers, 2022-01-0647, ISSN: 0148-7191. DOI:
10.4271/2022-01-0647.
Forder, M,
Morris, N, King, P, Balakrishnan, S, Howell-Smith, S (2022)
An experimental investigation of low viscosity lubricants on three piece oil control rings cylinder liner friction,
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 236(11), pp.2261-2271, ISSN: 1350-6501. DOI:
10.1177/13506501221076892.
Minas, I,
Morris, N, Theodossiades, S, O’Mahony, M, Voveris, J (2021)
Automotive dry clutch fully coupled transient tribodynamics,
Nonlinear Dynamics, 105(2), pp.1213-1235, ISSN: 0924-090X. DOI:
10.1007/s11071-021-06605-x.
Leighton, M,
Morris, N, Rahnejat, H (2021)
Transient nanoscale tribofilm growth: analytical prediction and measurement,
Applied Sciences, 11(13), 5890, ISSN: 2076-3417. DOI:
10.3390/app11135890.
Umer, J,
Morris, N, Rahmani, R, Rahnejat, H, Howell-Smith, S, Balakrishnan, S (2021)
Effect of dispersant concentration with friction modifiers and anti-wear additives on the tribofilm composition and boundary friction,
Journal of Tribology, 143(11), 111901, ISSN: 0742-4787. DOI:
10.1115/1.4050017.
Morris, N, Hart, G, Wong, YJ, Simpson, M, Howell-Smith, S (Accepted for publication) Laser Surface Texturing of Wankel Engine Apex Seals, Surface Topography: Metrology and Properties, DOI: 10.1088/2051-672x/ababf5.
Morris, N, Johns-Rahnejat, P, Rahnejat, H (2020)
Tribology and Dowson,
Lubricants, 8(6), 63, DOI:
10.3390/lubricants8060063.
Minas, I,
Morris, N, Theodossiades, S, O’Mahony, M (2020)
Noise, vibration and harshness during dry clutch engagement oscillations,
Proceedings of the Institution of Mechanical Engineers Part C: Journal of Mechanical Engineering Science, 234(23), pp.4572-4588, ISSN: 0954-4062. DOI:
10.1177/0954406220927065.
Forder, M, Umer, J,
Morris, N, Rahmani, R, Howell-Smith, S, Rahnejat, H (2020)
Asperity level frictional interactions of cylinder bore materials and lubricant composition,
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 235(4), pp.679-686, ISSN: 1350-6501. DOI:
10.1177/1350650120903928.
Umer, J,
Morris, N, Rahmani, R, Balakrishnan, S, Rahnejat, H (2019)
Nanoscale frictional characterisation of base and fully formulated lubricants based on activation energy components,
Tribology International, 144, 106115, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2019.106115.
Dolatabadi, N, Forder, M,
Morris, N, Rahmani, R, Rahnejat, H, Howell-Smith, S (2019)
Influence of advanced cylinder coatings on vehicular fuel economy and emissions in piston compression ring conjunction,
Applied Energy, 259, 114129, ISSN: 0306-2619. DOI:
10.1016/j.apenergy.2019.114129.
Morris, N, Patel, R, Rahnejat, H (2019)
Hydrodynamic lubricant film separation during co-directional and counter-directional rotations of disengaged wet clutch packs,
Journal of Fluids Engineering, 142(1), 011104, ISSN: 0098-2202. DOI:
10.1115/1.4044443.
Morris, N, Davies, JA, Leighton, M, King, P, Rahnejat, H (2019)
Oil film separation and drag torque in disengaged wet brakes,
Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 234(1), pp.17-27, ISSN: 0954-4070. DOI:
10.1177/0954407019844358.
Humphrey, E,
Morris, NJ, Rahmani, R, Rahnejat, H (2018)
Multiscale boundary frictional performance of diamond like carbon coatings,
Tribology International, 149, 105539, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2018.12.039.
Umer, J,
Morris, N, Leighton, M, Rahmani, R, Balakrishnan, S, Rahnejat, H (2018)
Nano and microscale contact characteristics of tribofilms derived from fully formulated engine oil,
Tribology International, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2018.11.007.
Kozuch, E, Nomikos, P, Rahmani, R,
Morris, N, Rahnejat, H (2018)
Effect of shaft surface roughness on the performance of radial lip seals,
Lubricants, 6(4), DOI:
10.3390/lubricants6040099.
Teo, WJ, Dolatabadi, N, Rahmani, R,
Morris, N, Rahnejat, H (2018)
Combined analytical and experimental evaluation of frictional performance of lubricated untextured and partially textured sliders,
Lubricants, 6(4), DOI:
10.3390/lubricants6040088.
Minas, I,
Morris, N, Theodossiades, S, O'Mahony, M (2018)
Influence of clutch tribodynamics on drivetrain noise, vibration and harshness, (NVH), phenomena,
SAE International, ISSN: 0148-7191. DOI:
10.4271/2018-01-1537.
Humphrey, E,
Morris, N, Leighton, M, Rahmani, R, Rahnejat, H (2018)
Multiscale friction in lubricant-surface systems for high performance transmissions under mild wear,
Tribology Letters, 66, 77, ISSN: 1023-8883. DOI:
10.1007/s11249-018-1032-z.
Leighton, M,
Morris, N, Trimmer, G, King, P, Rahnejat, H (2018)
Efficiency of disengaged wet brake packs,
Proc. IMechE, Part D: Journal of Automobile Engineering, ISSN: 0954-4070. DOI:
10.1177/0954407018758567.
Morris, N, Shahmohamadi, H, Rahmani, R, Rahnejat, H, Garner, C (2018)
Combined experimental and multiphase computational fluid dynamics analysis of surface textured journal bearings in mixed regime of lubrication,
Lubrication Sciences, ISSN: 0954-0075. DOI:
10.1002/ls.1414.
Morris, N, Mohammadpour, M, Rahmani, R, Johns-Rahnejat, PM, Rahnejat, H, Dowson, D (2018)
Effect of cylinder deactivation on tribological performance of piston compression ring and connecting rod bearing,
Tribology International, ISSN: 1879-2464. DOI:
10.1016/j.triboint.2017.12.045.
Umer, J,
Morris, N, Leighton, M, Rahmani, R, Howell-Smith, SJ, Wild, R, Rahnejat, H (2017)
Asperity level tribological investigation of automotive bore material and coatings,
Tribology International, ISSN: 1879-2464. DOI:
10.1016/j.triboint.2017.08.023.
Morris, N, Rahmani, R, Rahnejat, H (2017)
A hydrodynamic flow analysis for optimal positioning of surface textures,
IMECHE Part J: Journal of Engineering Tribology, 231(9), ISSN: 1350-6501. DOI:
10.1177/1350650117709672.
Gore, M,
Morris, N, Rahmani, R, Rahnejat, H, King, P, Howell-Smith, SJ (2017)
A combined analytical-experimental investigation of friction in cylinder liner inserts under mixed and boundary regimes of lubrication,
Lubrication Science, 29(5), pp.293-316, ISSN: 0954-0075. DOI:
10.1002/ls.1369.
Leighton, M,
Morris, N, Rahmani, R, Rahnejat, H (2017)
Surface specific asperity model for prediction of friction in boundary and mixed regimes of lubrication,
Meccanica, pp.1-13, ISSN: 0025-6455. DOI:
10.1007/s11012-016-0397-z.
Morris, N, Mohammadpour, M, Rahmani, R, Rahnejat, H (2017)
Optimisation of piston compression ring for improved energy efficiency of high performance race engines,
Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, ISSN: 2041-2991. DOI:
10.1177/0954407016686249.
Leighton, M,
Morris, N, Gore, M, Rahmani, R, Rahnejat, H, King, P (2016)
Boundary interactions of rough non-gaussian surfaces,
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, ISSN: 1350-6501. DOI:
10.1177/1350650116656967.
Mohammadpour, M,
Morris, N, Leighton, M, Rahnejat, H (2015)
Effect of surface topography upon micro-impact dynamics,
Surface Topography: Metrology and Properties, 4(1), 014001, DOI:
10.1088/2051-672X/4/1/014001.
Morris, NJ, Rahmani, R, Rahnejat, H, King, P, Howell-Smith, S (2015)
A numerical model to study the role of surface textures at top dead center reversal in the piston ring to cylinder liner contact,
Journal of Tribology: Transactions of the ASME, 138(2), pp.021703-021703, ISSN: 1528-8897. DOI:
10.1115/1.4031780.
Tang, T,
Morris, N, Coupland, J, Arevalo, L (2015)
Cavitation bubble measurement in tribological contacts using digital holographic microscopy,
TRIBOLOGY LETTERS, 58, 5, ISSN: 1023-8883. DOI:
10.1007/s11249-015-0488-3.
Morris, N, Leighton, M, De la Cruz, M, Rahmani, R, Rahnejat, H, Howell-Smith, SJ (2014)
Combined numerical and experimental investigation of the micro-hydrodynamics of chevron-based textured patterns influencing conjunctional friction of sliding contacts,
Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology, 229(4), pp.316-335, ISSN: 1350-6501. DOI:
10.1177/1350650114559996.
Morris, N, Rahmani, R, Rahnejat, H, King, P, Fitzsimons, B (2013)
Tribology of piston compression ring conjunction under transient thermal mixed regime of lubrication, ISSN: 0301-679X. DOI:
10.1016/j.triboint.2012.09.002.
Morris, NJ, Rahmani, R, Rahnejat, H, King, PD, Fitzsimons, B (2013)
The influence of piston ring geometry and topography on friction, ISSN: 1350-6501. DOI:
10.1177/1350650112463534.
Conferences
Smart, N, Hooker, R, Bhattacharjee, R, Rahmani, R,
Morris, N, Maiti, R (2024)
Characterising the mechanism of cell failure due to shear using a combined numerical and analytical approach. In Ball, AD, Ouyang, H, Sinha, JK, Wang, Z (ed)
UNIfied Conference of DAMAS, IncoME and TEPEN Conferences (UNIfied 2023); Proceedings of the UNIfied Conference of DAMAS, IncoME and TEPEN Conferences (UNIfied 2023), Huddersfield, UK, pp.259-259, ISBN: 9783031494208. DOI:
10.1007/978-3-031-49421-5_20.
Simpson, M, Mughal, H, Berland, M, Dolatabadi, N, Rahmani, R, Fuller, J, Lovett, I,
Morris, N (2023)
Tribology of hydrogen fuelled Wankel engines [Abstract]. In
48th Leeds-Lyon Symposium on Tribology (Leeds-Lyon 2023), Leeds, UK.
Morris, N, Forder, M, Dolatabadi, N, King, P, Rahmani, R, Rahnejat, H, Howell-Smith, S (2023)
Oil control ring friction and low viscosity lubricants: A combined numerical and experimental analysis. In
Eight European Conference and Exhibition on ‘Lubrication Maintenance and Tribotechnology’ (LUBMAT) 2023; Eight European Conference and Exhibition on ‘Lubrication Maintenance and Tribotechnology’ (LUBMAT) 2023, Manchester, UK.
Minas, I,
Morris, N, Theodossiades, S, O’Mahony, M, Voveris, J (2023)
A methodology to study automotive brake and dry clutch NVH. In
VDI Conference on Clutch and Brake Systems for Mobile and Stationary Applications; Conference Proceedings of the VDI Conference on Clutch and Brake Systems for Mobile and Stationary Applications, Karlsruhe, Germany.
Tomlinson, K,
Morris, N, King, P, Slatter, T,
Morris, N (2023) Measuring the frictional behaviour of lubricants with an antiwear additive and different friction modifiers. In
77th STLE Annual Meeting & Exhibition, Long Beach Convention Center, USA.
Minas, I,
Morris, N, Theodossiades, S, O'Mahony, M, Voveris, J (2021)
Modelling and simulation of transient clutch system dynamics. In (IMechE), IOME (ed)
Powertrain Systems for Net-Zero Transport; Powertrain Systems for Net-Zero Transport, IMechE London, pp.163-172, ISBN: 9781032112831.
Minas, I,
Morris, N, Theodossiades, S, O'Mahony, M, Voveris, J (2020)
On the Effect of Clutch Dynamic Properties on Noise, Vibration and Harshness Phenomena. In
ISNVH: Integrating Seamlessly NVH, SAE Technical Papers, Graz Austria / Online. DOI:
10.4271/2020-01-1510.
Humphrey, E,
Morris, N, Rahmani, R, Rahnejat, H (2019)
Tribological performance of surface-lubricant systems for automotive transmissions [Abstract]. In
7th European Conference on Tribology (EcoTrib 2019), Vienna, Austria.
Umer, J,
Morris, N, Leighton, M, Rahmani, R, Howell-Smith, SJ, Rahnejat, H (2018)
Characterisation of automotive bore material and coatings using atomic force microscopy [Abstract]. In
TriboUK2018, University of Sheffield.
Umer, J, Leighton, M,
Morris, N, Rahmani, R, Rahnejat, H, Balakrishnan, S (2018)
Tribological investigation of organic and inorganic friction modifiers with varying quantities of dispersants [Abstract]. In
Leeds Lyon 2018, University of Leeds.
Martinez-Insua-Rodriguez, A, Rahnejat, H, Smith, MB, Rahmani, R,
Morris, N, Umer, J, Howell-Smith, SJ (2018)
Study of the lubricant-surface system for in-cylinder applications [Abstract]. In
TriboUK2016, Univeristy of Leeds.
Kozuch, E, Nomikos, P,
Morris, N, Rahmani, R, Rahnejat, H (2018)
Performance evaluation of radial shaft seals of automotive transmission systems [Abstract]. In
24th International Conference on Fluid Sealing (FS 2018), Manchester.
Humphrey, E,
Morris, N, Rahmani, R, Rahnejat, H (2018)
Lubricant-surface system characterisation for high performance transmissions [abstract]. In
45th Leeds-Lyon Symposium on Tribology: Smart Tribology Systems, University of Leeds.
Kozuch, E, Nomikos, P,
Morris, N, Rahmani, R, Rahnejat, H (2018)
Shaft surface as a factor affecting lip seal performance. In
TriboUK 2018, University of Sheffield.
Forder, M, Umer, J,
Morris, N, King, P, Howell-Smith, SJ, Rahnejat, H (2018)
Lubricant base stock-surface interaction. In
3rd International Brazilian Conference on Tribology-TriboBR 2018, Florinopolis Brazil.
Umer, J,
Morris, N, Rahmani, R, Rahnejat, H, Balakrishnan, S (2018)
Interaction of dispersants with anti-wear and friction modifiers in contacts representative of piston-ring liner interface [Abstract]. In
3rd International Conference on Tribology-TriboBR 2018, Florianopolis, Brazil.
Nomikos, P, Kozuch, E,
Morris, N, Rahmani, R, Rahnejat, H (2018)
Measurement of vibrations affecting the power transmission seals. In
4th Biennial International Conference on Powertrain Modelling and Control (PMC 2018), Loughborough University.
Humphrey, E, Elisaus, V,
Morris, N, Rahmani, R, Theodossiades, S, Mohammadpour, M (2018)
Effect of coating on transmissions efficiency [Abstract]. In
TriboBR 2018, Florianópolis, Brazil.
Kozuch, E, Nomikos, P, Rahmani, R,
Morris, N, Rahnejat, H (2018)
Evaluating leakage from radial lip seals affected by bearing area of shaft topography. In
20th ISC – International Sealing Conference Stuttgart 2018, University of Stuttgart.
Humphrey, E,
Morris, N, Rahmani, R, Rahnejat, H, Rapson, G (2017)
A test procedure to investigate lubricant-surface combination for high performance racing transmissions. In
World Tribology Congress 2017, Beijing, China.
Umer, J,
Morris, N, Leighton, M, Rahmani, R, Rahnejat, H, Howell-Smith, SJ, Balakrishnan, S (2017)
Nano-scale investigation of frictional characteristics of tribo-films in sliding contacts of representative in-cylinder conditions. In
6th World Tribology Congress, Beijing, China.
Leighton, M, Davies, JA,
Morris, N, Rahnejat, H, Trimmer, G (2017)
A combined numerical and experimental investigation of disengaged wet clutch system power loss. In
World Tribology Congress 2017, Bejing.
Morris, N, Suzuki, H, Shahmohamadi, H, Dwyer-Joyce, RS, Rahnejat, H (2016)
Combined numerical and experimental investigation of surface textured journal bearings [Abstract]. In
Leeds-Lyon Symposium, Leeds Trinity University.
Morris, N, Leighton, M, Rahmani, R, Rahnejat, H (2016)
Hydrodynamic flow analysis for determination of the location of surface texture features. In
43rd Leeds-Lyon Symposium on Tribology, University of Leeds.
Leighton, M,
Morris, N, Rahmani, R, Trimmer, G, King, P, Rahnejat, H (2016)
A combined numerical and experimental investigation of disengaged wet brake plate power loss. In
3rd Biennial International Conference on Powertrain Modelling and Control (PMC 2016), Loughborough University.
Humphrey, E, Gkinis, T,
Morris, N, Leighton, M, Rahmani, R, Rahnejat, H (2016)
Clutch lining frictional characteristics under thermal tribodynamic conditions. In
3rd Biennial International Conference on Powertrain Modelling and Control (PMC 2016), Loughborough University.
Umer, J, Rahnejat, H, Rahmani, R, King, P, Martinez-Insua-Rodriguez, A,
Morris, N (2016)
Lubricant-surface system mitigating in-cylinder friction. In
TriboUK 2016, University of Leeds, UK.
Leighton, M,
Morris, N, Rahmani, R, Rahnejat, H (2015)
Asperity contact modelling for measured surfaces. In
11th International Tribology Conference, presented by The South African Institute of Tribology (SAIT), Pretoria, South Africa.
Morris, N, Shahmohamadi, H, Rahmani, R, Rahnejat, H (2015)
A CFD study comparing surface texture features on stationary and entraining surfaces. In
42nd Leeds-Lyon Symposium on Tribology, Lyon, France.
Leighton, M,
Morris, N, Rahmani, R, Rahnejat, H (2015)
An averaged approach to asperity contact interactions for non-gaussian lubricated surfaces. In
42nd Leeds-Lyon Symposium on Tribology, Lyon, France.
Tang, T,
Morris, N, Coupland, J (2015)
Optical measurements of cavitation in tribological contacts. In
, 9th International Symposium on Cavitation (CAV2015), Laussane Switzerland. DOI:
10.1088/1742-6596/656/1/012119.
Morris, N, Leighton, M, Rahmani, R, De-La-Cruz, M, Rahnejat, H (2014)
Friction reduction in piston ring cylinder liner contact using textured surfaces. In
LUBMAT 2014, Manchester, UK.,ISBN: 978-1-909755-02-4.
Leighton, M,
Morris, N, Rahmani, R, Rahnejat, H (2014)
The influence of large scale surface roughness on flow factors. In
, Sinaia, Romania, pp.217-223.
Morris, N, De la Cruz, M, Rahmani, R, Leighton, M, Rahnejat, H, King, P (2013)
A numerical and experimental approach in understanding the performance of textured surfaces in sliding contacts. In
,ISBN: 9788890818509.
De la Cruz, M, Gore, M,
Morris, N, Rahnejat, H (2012)
The Role of Laser Surface Textured Patterns on Friction in Reciprocating Contacts. In
ASME/STLE 2012 International Joint Tribology Conference, pp.71-73, DOI:
10.1115/ijtc2012-61149.
Morris, N, Rahnejat, H, Rahmani, R, King, P, Fitzsimons, B (2012)
Performance evaluation of piston compression ring through accelerated wear in engine tests. In
,ISBN: 978-0-7918-4466-3. DOI:
10.1115/ICES2012-81201.
Morris, N, Rahmani, R, Rahnejat, H, King, PD, Fitzsimons, B (2011) Tribology of Piston Compression Ring Conjunction under Transient Thermal Mixed Regime of Lubrication. In
38th Leeds-Lyon Symposium on Tribology, Lyon, France.
Morris, N, Rahnejat, H, Rahmani, R (2011)
Tribology of partial pad journal bearings with textured surfaces. In
.
Morris, N, Rahmani, R, Rahnejat, H, King, PD (2011) Optimizing Piston Ring Topography to Minimize Running-in Wear in Mixed Regime of Lubrication. In
ASME/STLE 2011 International Joint Tribology Conference (IJTC2011), Paper No. IJTC2011-61090, Los Angeles, California, USA.
Bleger, A, Morris, N, Leighton, M (Accepted for publication) Experimental and numerical investigation of electric erosion in automotive motor bearings. In .
