Study on influences on the technical process and characteristics of infrared emission compositions

Study on influences on the technical process and characteristics of infrared emission compositions

Tran Minh Cong^*, Le Trong Thiep, Pham Quang Dinh, Bach Nhat Hong

In this papers, we are presented the influences of polivinylcloride (PVC) molecular mass on the dissolution time, viscosity of PVC solution, moisture adsorption, mechanico- physical properties of pyrotechnic charge and the influences of oxidant – fuel ratio, particle sizes on the energy charateristics of pyrotechnic compositions.

1. 
   INTRODUCTION
   

2. 
   EXPERIMENTAL
   

The test methods for the viscosity of PVC solution, heat of combustion, gaseous products volume, temperature of combustion, moisture adsorption,... all were determinated according to Vietnam National Standards and ASTM.

The equipments which used to do experiment are capilar viscometer (Germany); measuring mechniccal strengths by Hounsfield (UK), calorimeter (Parr 1261 - USA), computerized Speetroradiomer CI-SR 5000 (Israel),…

3. 
   rESULTS AND DISCUSSION
   

The paper [1] had showed the effection of polimer kind and content in the infrared emission compositions. Herein the influences of PVC molecular mass to technical process, moiture adsorption, mechanico- physical properties of infrared emission compositions charge.

The composition was formulated from the following ingredients:

Ingredients	Weight percent
Potassium perchlorate	15
Potassium nitrate	29
Boron (powder)	8
Silica (powder)	8
Aluminium- Magnesium alloy (powder)	40

PVC molecular mass were choiceed 43,000; 62.000; 80.000; 97.000; 223.000 and used as a binder in content 5%, respectively. The PVC solution was prepared by dissolution PVC in cyclohexanone and methylethylcetone in 5% concentration. All of these ingredients were mixed careffully, then made into particles, dry and compressed into cylinder to determine tensile strength.

1.1. Influence of PVC molecular mass on the viscosity, dissolution time and cone penetration time of compositions:

PVC with different molecular mass were dissolved in the same volume of cyclohexanone and methylethylcetone to receive solution. Dissolution time was determined from the beginning PVC put into solvent to the finish dissolution. Then, all of these solutions were diluted into 1% solutions by solvent.

PVC used in the test samples has molecular mass 43,000; 62,000; 80,000; 97,000; 223,000, respectively made to form composition charges. After that, it were determined moiture adsorption and tensile strengths after keep samples at 250C, 100% in humidity.

In the compositions, the weight percent of PVC, Bo and Si powder were maintained in 5%, 8%, 8%, respectively, but oxidant – fuel weight percent was changed to determine physical- chemical characteristics of compositions.

Generally, the fuel particle size has effect strongly to velocity of combustion, inflamability and burning maintenance.

Sample for test was prepared by pressing composition into the tube Φ19 under presure 2.000 kG/cm2 with Al- Mg alloy powder (100 to 200 μm). The height of sample is 45 mm. The resutls showed in table 4:

Table 4: Influence of Al- Mg alloy particle size to combustion time of infrared emission compositions

No.	Al-Mg alloy particle size (through net No)	Time of combustion
1	100	38.4 – 41.3
2	120	32.3 – 35.5
3	140	24.6 – 28.4
4	160	17.5 - 19.5
5	180	15.4 – 16.8
6	200	12.3 – 13.6

As results in table 4 show that the Al-Mg alloy particle size has strongly effect to velocity of combustion. When the Al-Mg alloy particle size decrease, time of combustion also decreases. It is a base to choice technical process for making infrared emission composition. Normaly, velocity of combustion of infrared emission composition is 1.5 to 2.0 mm/s (35,5 to 24,6s, respectively). So that, Al-Mg particle with 120- 140 net size is the most suitable.

IV. Conclusion

When the PVC molecular mass from about 43,000 to about 80,000 is increased, the disolution time, viscosity, cone penetration will be also increased. It is really useful to establish technical process for making composition.

The PVC molecular mass increased to 80,000 is the most suitable. Obtained products has small moiture adsorption, hight compress tensile due to binder distributed homogenously, easy mixing and forming. When the mass of PVC is higher than 80,000, the obtained products will be have higher humidity adsorption.

When the Al-Mg alloy ratio in the infrared emission compossition is increased from about 25% to about 40%, the head of combustion will be increased, while temperature of combustion and gaseous products volume will be decreased. If the content of Al- Mg alloy more increases, the energetic characteritics will be worse. This is a base to choice infrared emission compositions HN-07. It meet the required conditions in technical characteristics.

The Al-Mg alloy particle size decreases, time of combustion will be increased . The net size from about 120 to about 140 is the most suitable.

References

1. 
   Tran Minh Cong, Le Trong Thiep, Journal of Applied Chemistry (SRV), No. 5 (77), pp.39-41, 2008.
   
2. 
   John A. Conkling, Chemistry of pyrotechnics Basic Principles and Theory, Marcel Dekker, Inc., New York., 1985.
   
3. 
   Berger B., Hass B., and Reinhard G., Influence of Binder Content on the Reaction Behavior of Pyrotechnic Mixture, Proc. 26th Inter. Annual Conference of ICT, 1995.
   

PROBLEM OF SUSTAINABLE ENERGY AND THE TECHNOLOGICAL SOLUTIONS OF SOLAR POWER SATELLITE SYSTEM FOR SOLAR ENERGY RECEIVING, CONVERTING, AND TRANSMITTING IN FORM OF THE HIGH POWER MICROWAVE AND/OR LASER BEAM FROM THE SPACE ORBIT TO THE EARTH’S SURFACE

Dao Khac An^*

Institute of Materials Science (IMS) , Vietnam Academy of Science and Technology (VAST), 18 Hoang Quoc Viet Road, Cau Giay, Hanoi, Vietnam
Abstract

Currently the problem of sustainable energy is very interested in the World. So far, many energy sources have been exploiting and using such as energy from the coal, petroleum, nuclear, renewable energy.., but each kind of these energy sources has own problems and their amounts are also very limited. Recently the scientists and technologists have intensively concentrated their activities to find new sources of clean energy. Space Solar Power gathers energy from sunlight in space and transmits it wirelessly to the Earth in the forms of high power microwave beam or high power laser beam which is the promise sustainable energy source. The equipment system concerning is, so called, Solar Power Satellite (SPS). The Governments of some developed countries have been investing some tens of billions USD for the research activities expecting to get sustainable energy for mankind in near future and for some other purposes. This review outlines briefly some situations of recently energy sources and the scientific technological solutions concerning receiving solar energy, convert to high power microwave beams and /or high power laser beam, transmitting to the Earth’s surface in the form of the electric energy. The review also outlines some problems and challenges for the wireless transfer of the high power microwave/Laser beam from the space orbit to the Earth surface. The current research projects over the World including in Vietnam and the several obtained results concerning will also be reported and discussed.

Keywords: sustainable energy, space solar power.

1. 
   INTRODUCTION
   

Recently the Mankind is facing with three big disastrous problems: those are sustainable energy, the lack of Food and environment changes. These problems are related together and mutual interaction each other. In order to produce the various kinds of industrial and agricultural products we need the more energy. When we use more kinds of energy sources, especially the traditional energy sources (coal/peat, oil, nuclear energy) they could emit more waste, toxic gases (CO₂, NO_x), these will cause the environmental changes. Recently there are 7 environmental problems that are worse then we thought. These problems include: the mammal extinction, the ocean dead zones, collapsing Fish stock, destruction of the rain forest, polar sea ice loss, increasing CO₂ levels in the atmosphere, population explosion. In this presentation we will report mainly some aspects of problems concerning the sustainable energy and then offer shortly the scientific technological solutions of Solar Power Satellite (SPS) which receive solar energy in the space then convert to the high power microwave beam/high power laser beam, transmit to the Earth surface.

2. 
   THE PROBLEMS OF SUSTAINABLE ENERGY
   
   2. 
      Some situation and data of energy sources
      

According to the data of the International Energy Agency - IEA the world total primary energy supply (TPES) by fuel and the regional shares of total final consumption in 1973 and in 2006 can see on Fig. 1a,b). Their values are 11 741 Mte and 8.084 Mtoe for 2006, respectively. From the Fig. 1a,b) we also can see the ratio in percent (%) of each kinds of energy sources in comparison and the energy consumption in each region on the World. Here we would like to emphaze shortly some points:

- Energy from coal/peat production according to the most current and authoritative research predicts that global peaking coal production will reach to peak around 2025, [36]

- Energy from oil production, which is the most import energy source recently, according to the most current and authoritative research predicts that the global oil production will reach to peak during the 2008 to 2018 timeframe. In a worst-case scenario, global oil production may reach its peak in 2008, before starting to decline (Fig.2.a, b). In a best-case scenario, this peak would not be reached until 2018 [3]. Recently we can not run out of petroleum, although so far nothing close to the efforts envisaged have yet begun but we may do in future. It will require more than a decade to transition our civilization away from our heavy dependence on oil.

Каталог: activities -> clv -> clv10
activities -> Phiếu Ghi Danh (xin điền mỗi người một phiếu)
activities -> Dương Ngọc Tùng(*), Vũ Hữu Khánh

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