Александров Николай Леонидович
Факультет физики
Профессиональные интересы
Должности
- Профессор — Факультет физики
Био
- · Начал работать в НИУ ВШЭ в 2022 году.
- · Научно-педагогический стаж: 50 лет.
Образование
- 1999 · Ученое звание: Профессор
- 1992 · Доктор физико-математических наук
- 1975 · Специалитет: Московский физико-технический институт, специальность «Летательные аппараты», квалификация «Инженер-физик»
Опыт работы
- · 1975: Окончил факультет аэрофизики и космических исследований МФТИ в году
- · Опыт работы: старший инженер (каф. физической механики МФТИ) 01.09.1975-31.12.1975; старший научный сотрудник (каф. физической механики МФТИ) 01.01.1976-31.08.1994; доцент (каф. прикладной физики МФТИ) 01.09.1994-31.08.2007; профессор (каф. прикладной физики МФТИ ) 01.09.2007-31.08.2014; главный научный сотрудник и зав. лабораторией импульсных плазменных систем МФТИ 01.09.2014-30.12.2019; профессор и зам. зав. каф. прикладной физики 31.12.2019-по настоящее время.
- · Научная работа: индекс Хирша 27 (Scopus) и 23 (Web of Science). Опубликовано более 200 печатных работ в российских и международных журналах. Под моим научным руководством защищено 4 кандидатских диссертации. Область научных интересов: физика низкотемпературной плазмы, газовые разряды, процессы переноса и элементарные процессы в плазме, приложения низкотемпературной плазмы.
- · Член Научного совета РАН по физике низкотемпературной плазмы
- · Член Экспертного совета МФТИ по физико-математическим наукам
- · Член редколлегии журнала РАН «Физика плазмы»
- · Член редколлегии журнала РАН «Письма в ЖЭТФ»
- · Член Advisory Panel of Journal of Physics D: Applied Physics (IOP Publishing, Bristol, UK)
- · Эксперт Министерства науки и высшего образования РФ, Российского научного фонда, Российского фонда фундаментальных исследований, Нидерландского фонда научных исследований, Чешского научного фонда, фонда Научно-технологического университета имени короля Абдаллы (Саудовская Аравия)
- · Почётный работник высшего профессионального образования РФ.
Награды и поощрения
- · Благодарность факультета физики НИУ ВШЭ (февраль 2024)
- · Надбавка за публикацию в журнале из Списка А (и приравненном к нему научном издании) (2025–2026, 2024–2025, 2023–2024)
- · Лучший преподаватель — 2023–2024
Идентификаторы исследователя
- ORCID:
0000-0001-6637-1611 - ResearcherID:
L-3038-2013 - SPIN РИНЦ:
5303-5158 - Scopus AuthorID:
7102893376
Публикации (18)
Simple methods for calculating the transport and rate properties of heavy ions in helium in strong electric field
2026 · ARTICLE · en
The Smirnov method for obtaining the drift velocity of heavy ions in a light gas is generalized to calculate the rate coefficients of threshold ion–molecule reactions. Different versions of this simple method are used to calculate the mobility and rate coefficients for O4−,O2−, and NO− ions moving through helium under the influence of an electric field. Calculated results are validated by comparing these data with Monte Carlo simulation results. The simple methods allow to reach agreement with a more sophisticated Monte Carlo simulation and to reduce the computational time by orders of magnitude.
An Approximate Method for Calculating Kinetic Coefficients of Heavy Ions in He-Containing Mixtures in a Strong Electric Field
2026 · ARTICLE · en
An approximate method for calculating drift velocity and other kinetic coefficients of heavy ions in a light gas is generalized to gaseous mixtures. Obtained equations are used to calculate the mobilities of and ions, as well as rate constants for inelastic ion–molecule processes with these ions in helium with small additions of O2 under an electric field. Calculated results are compared with the results of Monte Carlo simulation. Simple approximate methods allow good agreement to be reached with more complicated Monte Carlo simulation when describing the strong effect of small O2 concentrations on the ion kinetic properties in He and to shorten computational time by orders of magnitude.
Numerical simulation of lightning channel reactivation in recoil leader process
2025 · ARTICLE · en
Lightning development involves transient events that produce non-stationary, abrupt changes in lightning structure. The most prominent (and most studied) examples of reactivation of lightning side branches are recoil leaders that are initiated near the tips of previously decayed positive leader channels. This study proposes a numerical model that, among other things, takes into account evolution of channel temperature profile and is aimed at simulation the recoil leader inception. The model is based on the paradigm of reversal point meandering, which is a consequence of the macroscale asymmetry of development of positive and negative lightning poles. Simulation results allow one for the first time to formulate a physically-based and well-founded mechanism of a negative recoil leader initiation. In particular, it is shown that the channel reactivation is pro vided by the wave of electric field that starts from the branching point and propagates along a previously decayed (but still heated) leader channel when its per-unit-length resistance does not exceed several thousand Ohms per meter. This resistance corresponds to the channel temperature no less than ∼3500 K under equilibrium conditions. It is shown that channel reactivation starts somewhere between the branching point and the previ ously decayed leader tip, in agreement with observations. Additionally, the plasma chemical aspects of the leader channel reactivation are discussed.
A Simplified Approach to Describing the Kinetic Properties of Impurity Ions in a Weakly Ionized Helium Plasma
2024 · ARTICLE · en
Using an approximate approach that is valid for a large ratio of the ion mass to the mass of the neutral particle, the mobility of O2+, N2+, O2-, and O4- ions was calculated in helium and good agreement was obtained with the available results of Monte Carlo calculations and experimental data at high values of the reduced electric field. This simplified approach was used to determine the average energy of O4- ions and the rate constants of dissociation of these ions in helium. The obtained ion characteristics were compared with the results of more accurate calculations using the Monte Carlo method. Good agreement has been obtained between these two approaches for the average ion energy, but for the dissociation rate constant the difference is quite significant, reaching an order of magnitude or more. It was shown that this difference is associated with the peculiarities of the energy distribution of ions for a large ratio of the ion mass to the mass of the neutral particle.
Monte Carlo simulation of O2- ion transport and rate properties in noble gases with O2 addition
2024 · ARTICLE · en
The kinetics of O2- ions was numerically studied in He and Ar with a small admixture of O2 in a strong electric field through a Monte Carlo simulation. Cross-sections for elastic scattering between O2- ions and He and Ar atoms were determined by adjusting cross-section values to obtain good agreement between calculated and measured ion mobilities in pure helium and argon. Ion transport coefficients, mean energy and detachment rate were calculated for various mole fractions of O2 and values of the reduced electric field. It was shown that the O2- ion mobility, mean energy and detachment rate in He:O2 mixtures are much higher than those in Ar:O2 mixtures and air. A great difference between the properties of O2- ions in He-O2 and Ar-O2 mixtures was explained on the basis of the difference in the polarizability and mass for He and Ar atoms. Calculated detachment rates can be used for simulating guided ionization waves in He and Ar flows ejected into ambient air.
Generation of seed electrons in guided ionization waves in He–O2 mixtures: The effect of negative ion cluster formation
2024 · ARTICLE · en
The kinetics of electrons and negative ions was numerically studied under the conditions, which are typical for multi-pulsed guided ionization waves in He flows ejected into ambient air. It was shown that, in He with a small admixture of O2 or air, O2- ions formed due to three-body electron attachment in the discharge afterglow are rapidly converted to O4- cluster ions in pulse off time. We suggested that seed electrons are generated at the leading edge of a pulse in two steps, and these steps are dissociation of O4- ions to form O2- ions followed by electron detachment from the O2- ions. The rate of O4- dissociation was calculated in He–O2 mixtures for various reduced electric fields on the basis of a Monte Carlo simulation. This rate, as well as the rate of electron detachment from O2- ions calculated previously, was used to simulate seed electron generation in a high-voltage nanosecond pulse in He–O2 mixtures for different gas pressures. It was shown that the formation of O4- ions drastically hinders the generation of seed electrons in multi-pulsed guided ionization waves in He–O2 and He–air mixtures.
Analysis of the efficiency of MHD cycle supported by nanosecond pulsed discharge pre-ionization
2023 · ARTICLE · en
A numerical analysis of plasma generation by a nanosecond pulsed discharge in a strong magnetic field was performed. A 2D model of the plasma formation and decay in magnetohydrodynamic (MHD) channel has been elaborated. A comparison with experimental results demonstrates good agreement between calculated and measured plasma distribution in the channel. Preliminary analysis of the efficiency of the MHD-generator based on the nanosecond dielectric barrier discharge flow pre-ionization shows that the ratio of the power required to maintain ionization in the flow to the power extracted from the flow in MHD process is ∼3% for an ideal Faraday MHD generator with segmented electrodes with BY ∼ 5 T and supersonic flow speed uZ ∼ 1600 m s−1 . Such a high energy efficiency of the generator allows us to consider this concept of the generator as promising for energy generation and flow control.
Monte Carlo simulation of ion kinetics in nitrogen and oxygen plasmas under non-uniform electric field conditions
2023 · ARTICLE · en
The kinetics of N4+ and O− ions was numerically studied in nitrogen and oxygen plasmas in a highly non-uniform electric field. Mean ion energy and reaction rate coefficients in a background gas at pressures from 1 to 10 Torr were calculated through a Monte Carlo simulation. The ion characteristics followed the local reduced electric field at high pressures, whereas nonhydrodynamic effects leading to a nonlocal dependence of the mean ion energy and rate coefficients on the field were obtained at low pressures. As a result, the rates of N4+ ion dissociation, electron detachment from O− ions, and charge exchange in collisions between O− and O2 lagged the local field value. The non-local effect on the ion rate coefficients was more profound when the field decreased in space. We suggested a simplified method of describing ion rates in spatially varying electric fields on the basis of the Monte Carlo simulation of these rates for uniform electric field conditions and mean ion energy calculations in non-uniform fields. This method is similar to the local-mean-energy approximation utilized for describing electron swarm parameters in varying electric fields. The results of the simplified method were compared with the results of the direct Monte Carlo simulation.
Динамика изменения состава отрицательных ионов вокруг гидрометеоров в грозовом облаке
2023 · ARTICLE · ru
В последнее время обсуждается новый механизм зарождения молниевого разряда в грозовом обла- ке, который основан на индуцированном шумом кинетическом переходе, заключающемся в росте концентрации атмосферных ионов во внутриоблачной среде под воздействием стохастического электрического поля движущихся в турбулентном воздушном потоке заряженных и поляризован- ных гидрометеоров (капли, снежинки, крупа, град). Источником шума являются всплески электри- ческого поля, которые происходят при столкновениях или сближениях гидрометеоров и сопровож- даются зажиганием бесстримерной короны. Ключевым моментом в этом сценарии является эста- фетный процесс, в котором новые центры ионизации при зажигании коронного разряда возникают на фоне пятен отрицательного ионного заряда, оставшихся от расплывающихся старых центров. Это приводит к постепенному росту концентрации отрицательных ионов, которые могли бы слу- жить источником свободных электронов при новом усилении электрического поля. В данной рабо- те теоретически исследуется возможность отрыва электронов от отрицательных ионов, образован- ных в бесстримерной отрицательной короне около гидрометеоров в условиях грозового облака. По- казано, что в этом случае доминирующими отрицательными ионами около коронирующих гидрометеоров являются кластерные ионы О2-(Н2О)k и O4-. Из расчетов следует, что при наложении сильного электрического поля электроны освобождаются не за счет прямого отрыва от кластерных ионов, а многоступенчато в последовательности, обратной той, что наблюдается в отсутствие поля при образовании кластерных ионов. В итоге для отрыва электронов от ионов типа О2-(Н2О)k требу- ются достаточно умеренные допробойные приведенные электрические поля на уровне 65 Тд.
Kinetics of charged species in non-equilibrium plasma in water vapor- and hydrocarbon-containing gaseous mixtures
2022 · ARTICLE · en
In this review we describe the kinetics of non-equilibrium discharge plasma when the ion composition is dominated by water or hydrocarbon ions. Plasmas with water ions are formed in atmospheric discharges and discharges in the presence of liquid water or water vapor, including plasma applications for air purification, medicine and combustion. Reactions with hydrocarbon ions play an important role in interstellar chemistry, plasma enhanced chemical vapor deposition, synthetic diamond film deposition and plasma assisted combustion. The modeling of water ion chemistry and chemistry of hydrocarbon-containing plasmas requires large amount of data on the rates of ion formation and loss. This review provides the core database for the rate coefficients describing the kinetics of charged particles in plasmas with water and hydrocarbon ions as a function of temperature, pressure, and local electric field. Particular attention is given to cluster ions, which are important at not-too-low gas pressures, whereas the majority of studies of ion–molecule reactions have been performed at low pressures in the absence of cluster ions. To illustrate importance of the described processes, the development of streamer discharges in long humid air gaps is discussed and the influence of water ions on the streamer properties is demonstrated. In addition, the decay of non-equilibrium plasma with water and hydrocarbon ions is analyzed in combustible gaseous mixtures excited by a repetitively pulsed nanosecond discharge.
Курсы (3)
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Actual problems of modern physics · 5 раза
2025/2026, 2024/2025, 2023/2024, 2022/2023, 2021/2022 · Бакалавриат · Анг
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Механика сплошных сред
2025/2026 · Бакалавриат · рус
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Физика сплошных сред · 3 раза
2024/2025, 2023/2024, 2022/2023 · Бакалавриат · рус