scholarly journals Simulation as a tool to improve wave heating in fusion plasmas

2015 ◽  
Vol 81 (5) ◽  
Author(s):  
S. Heuraux ◽  
F. da Silva ◽  
T. Ribeiro ◽  
B. Despres ◽  
M. Campos Pinto ◽  
...  
Keyword(s):  
Wave Propagation ◽  
Heating System ◽  
Current Drive ◽  
Magnetized Plasma ◽  
Lower Hybrid ◽  
Heating Systems ◽  
Wave Heating ◽  
Drive Systems ◽  
The Impact ◽  
Resonant Heating

Firstly, a brief overview will be given on different models that are able to describe the behaviour of wave propagation as a function of specific frequency ranges. Each range corresponds to different heating systems, namely, 20–100 MHz for the ion cyclotron resonant heating, 2–20 GHz for lower-hybrid heating or current drive, and 100–250 GHz for electron cyclotron resonant heating or current drive systems. The specification of every system will be explained in detail, including the typical set of equations and the assumptions needed to describe the properties of these heating or current drive systems, as well as their specific domains of validity. In these descriptions, special attention will be paid to the boundary conditions. A review of specific physical problems associated with the wave heating systems will also be provided. The review will detail the role of simulation in answering questions that arise from experiments on magnetized plasma devices devoted to fusion. A few examples that will be covered are the impact of edge turbulence on wave propagation and its consequences on heating system performance, the effects of fast particles and ponderomotive effects, among others. A study that is more focused on radio-frequency sheath effects will also be discussed. It shows that such simulations require very sophisticated tools to gain a partial understanding of the observations undertaken in dedicated experiments. To conclude this review, an overview will be given about the requirements and progress necessary to obtain relevant predictive simulation tools able to describe the wave heating systems used in fusion devices.

Observation of Parametric Decay of a Pumping Wave in Lower Hybrid Wave Heating and Current Drive Experiments at the FT-2 Tokamak

2019 ◽  
Vol 45 (12) ◽  
pp. 1134-1141 ◽  
Author(s):  
V. V. D’yachenko ◽  
A. N. Konovalov ◽  
A. Yu. Stepanov ◽  
A. B. Altukhov ◽  
E. Z. Gusakov ◽  
...  
Keyword(s):  
Current Drive ◽  
Lower Hybrid ◽  
Hybrid Wave ◽  
Lower Hybrid Wave ◽  
Parametric Decay ◽  
Wave Heating

The Design of High Voltage DC Power Supply of 4.6GHZ/500MW LHCD

2011 ◽  
Vol 135-136 ◽  
pp. 1027-1036 ◽  
Author(s):  
Xu Hao ◽  
Yi Yun Huang
Keyword(s):  
Steady State ◽  
Power Supply ◽  
Power Supply System ◽  
Heating System ◽  
Power Source ◽  
Supply System ◽  
Current Drive ◽  
Lower Hybrid ◽  
Dc Power ◽  
Lower Hybrid Current Drive

The steady-state and transient performances of the power supply system of LHCD (Lower Hybrid Current Drive) heating system are highly demanded which makes it difficult to design the power source. In this thesis, the method of designing the 4.6GHZ/6MW power source of LHCD of EAST is discussed. And the results of the experiment are provided and some special characteristics are analysed to prove the accuracy of the method.

Nonlinear heating system of modular-trigger and platform furnaces for firing bulk materials

2021 ◽  
pp. 10-17
Author(s):  
A. I. Nizhegorodov
Keyword(s):  
Electrical Power ◽  
Central Zone ◽  
Heating System ◽  
Heat Radiation ◽  
Bulk Materials ◽  
High Quality ◽  
Heating Systems ◽  
Nonlinear Heating ◽  
Quality Material ◽  
The Impact

The design of the suspended nonlinear heating system of modular-trigger and platform furnaces for firing vermiculite and other bulk materials is considered. Previously, the design of linear heating systems did not provide homogeneous heating of thermographed materials, the material in the clutch zones suffered sufficient thermal energy. In addition, overheating of the central zone increased the frequency of the impact of the heaters themselves, which affected the reliability of the furnace. The use of a nonlinear heating system has changed this distribution to the opposite. The power of the intuboxic heater exceeded the power of the central 1,2‒1,36 times depending on the ratio of the diameters of thin and thick (diameter of 4 mm) of the heaters. At the same time, not only their electrical power increased, but the heat radiation streams, falling onto the surface of the supply, which led to an increase in the temperature of the material being processed. The obtained values of the temperature of the vermiculite grains in the fitted zones of the firing module exceed the temperature of the vermiculite in the central zone by 26 %, while it is sufficient for high-quality material intimidation. Due to the use of nonlinear heating system, temperatures were redistributed on heated surfaces in favor of relatively cold previously intuition zones: the heat picture has changed to the opposite, that is, the cold cloth zones have become relatively hot. Ill. 8. Ref. 14.

Evaluation of the Effectiveness of Heating Systems Applied in City Buses

2013 ◽  
Vol 391 ◽  
pp. 185-190
Author(s):  
Maciej Bajerlein ◽  
Jerzy Merkisz ◽  
Pawel Daszkiewicz
Keyword(s):  
Heating System ◽  
Relative Increase ◽  
Optimum Temperature ◽  
Auxiliary Heating ◽  
Vehicle Interior ◽  
Heating Systems ◽  
Temperature Distributions ◽  
Stationary Conditions ◽  
Signal Converter ◽  
The Impact

The paper presents energy saving opportunities in by analyzing two types of auxiliary heating systems. Objects of study were two heaters differing in power requirements and fuel consumption (used for water heating system). The heaters were installed in city buses of the same layout and identical convector heaters fitted for optimum temperature of the vehicle interior and the engine. Through the use of a portable device SEMTECH DS (PEMS) the exhaust emissions of CO, HC, NOx, CO2 were measured. The testing of the heaters for emissions and the testing of the temperature distribution inside the vehicle were performed in stationary conditions, determining the impact of the heating on the energy consumption of the heaters and temperature comfort inside the vehicle. The measurements were performed for each vehicle at the same ambient temperature, which was about 10°C [2, 3, 5]. So that the temperature increase inside the vehicle could be compared the tested vehicles were conditioned before the measurement. The obtained temperature distributions were determined along with a relative increase in the temperature in the vehicle interiors heated by the tested objects. The temperature measurement was performed with the use of six thermocouples utilizing a signal converter - IOTECH PERSONAL DAQ 3000.

scholarly journals The indoor climate modelling and the economic analysis regarding the energetic rehabilitation of church

2020 ◽  
Vol 1 ◽  
pp. 67-73
Author(s):  
Florin-Emilian Turcanu ◽  
Marina Verdes ◽  
Vasilica Ciocan ◽  
Catalin George Popovici ◽  
Sebastian Valeriu Hudisteanu
Keyword(s):  
18Th Century ◽  
Environmental Issues ◽  
Heating System ◽  
Primary Energy ◽  
Virgin Mary ◽  
Climate Modelling ◽  
Indoor Climate ◽  
Heating Systems ◽  
The Impact ◽  
The Church

The paper describes the behaviour of a heating system with radiators in a cult building. There has commonly used in many churches with many shortcomings. The temperature distribution in the analysed space is simulated in 2D. The simulation is based on an example, the Cathedral of the Assumption of the Virgin Mary in Jassy. The heating system with radiators simulated with the FLUENT program, the results being edifying for the factual state of the building. An important aspect is the impact of these heating systems on the works of art, the church being the 18th — century edifice. Current environmental issues lead to the continuous development of technologies used to reduce primary energy consumption. Churches are an invaluable wealth, sheltering heritage elements preserved in museums and historic buildings. Unheated churches have been used for centuries. Then, after installing one or more different heating systems, signs of rapid degradation appeared.

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