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Hybrid cooling system for semiconductor detectors of X- and Gamma- Rays

Periodic Reporting for period 1 - SEMICOOL-H (Hybrid cooling system for semiconductor detectors of X- and Gamma- Rays)

Reporting period: 2015-04-01 to 2015-09-30

Semiconductor detectors for registration of X-rays and gamma rays are widely used in the nuclear industry, as well as for environment monitoring, for security and public safety, and in scientific research.
To meet performance requirements, detectors need to be cooled to liquid nitrogen temperatures (77K or -196°C). For this liquid nitrogen (LN2) is used filled in Dewar vessels. LN2 evaporates requiring regular refilling. This increases operating costs to replace the LN2 that has been consumed imposing the additional requirement of storing LN2 on site as well as safety issues that may arise when LN2 must be replenished.. A more elegant way to cool detectors would be to with an electrical cooler that eliminates the problems associated with LN2.. Such coolers are under development but designs developed thus far are not suitable for detectors because they are too big and not vibration free. A hybrid cooling system that combines advantages of LN2 cooling and electrical cooling would potentially be competitive.
Baltic Scientific Instruments, Ltd. (BSI) is a leading European supplier of semiconductor detectors and spectrometers for X-rays and Gamma-rays. Electrical coolers have recently become available suitable for hybrid cooling systems for semiconductor detectors. BSI is now developing a hybrid cooling system for semiconductor detectors as a new product. A prototype hybrid cooling system has been developed, but its performance due to low quality of electrical coolers. A prototype of an advanced hybrid cooling system is planned that addresses known problems and obtains satisfactory results. The current Phase 1 SME project was made to perform a feasibility study for such a product that includes analyses of technical feasibility and economic feasibility.
The study revealed that there is a growing market for hybrid cooling systems with a significantly lower overall cost to the customer. Analysis of potential manufacturing costs indicates that the product would generate attractive margins and that manufacturing has the potential to be financially very attractive. Therefore BSI is taking steps to develop the product and to bring it to market. SME Instrument financing for Phase 1 and Phase 2 would enable BSI to potentially become the world leader in this attractive niche market.
"During the Phase 1 feasibility study work was done according to tasks set forth in the project proposal:
Task. 1. Gathering of BSI Experience in Hybrid Cooling System Development
BSI has the experience o developing a prototype hybrid cooling system that did not meet requirements to be competitive. Preliminary market analyses were done. Ideas for improving the preliminary prototype were gathered and are used to proceed with the next prototype.

Task.2. Component Search for Hybrid Cooling System
A search was conducted of advanced components suitable for developing hybrid cooling system and selected components were analyzed. Two potential developers of specific Dewar vessel types were identified and technical specifications and price quotes were obtained. Nine producers of electrical cryocoolers were identified and their products analyzed. Two producers were chosen for the next steps of the prototyping process. Negotiations were carried out with both. Results of the comprehensive analysis of characteristics of electric cryocoolers were published in an article A.Sokolov A.Pchelintsev and V.Gostilo The analyses of the electric coolers characteristics for HPGe gamma-detectors, Nuclear and Radiation Safety, No 4, 2015 (""Ядерна та радiацiйна безпека"", Киев, Украина) Кiev, Ukraine (Journal is cited in SCOPUS).

Task. 3. Computer Modeling of Hybrid Cooling System
SolidWorks program was used to make computer models for the future hybrid cooling system. The simulation showed that preliminary selected types of the components are rather coordinated with each other by size and fit into integrated system. Computer modeling allowed to evaluate the maximum height and width of the Dewar’s vessel.

Task.4. Engineering Calculations for Hybrid Cooling System
In hybrid cooling systems boiling N2 condenses by electrical cooling and is returned to the volume of the Dewar vessel. Boiling of N2 is caused by the heat flowing from all parts which are in contact with liquid N2 including the walls of the Dewar vessel, condenser, and submersed cryostat. All these types of power flows, as well as heat of condensation of Nitrogen vapors, should be compensated by the electrical cooler. Calculation was done for the heat flow and minimal requirements for the power of electric coolers obtained.

Task.5. Analyses of Hybrid Cooling Systems of Competitors
Thorough analyses of hybrid cooling systems offered by competitors was undertaken. Advantages and disadvantages of different technical solutions were analysed.
The analyses of competitors gave assurance that BSI is capable of producing solutions with clear competitive advantage.

Task.6. Market Analyses for Hybrid Cooling Systems
Customer preferences to have (or not to have) hybrid cooling system for their spectrometers based on HPGe detectors include the following factors: marketing strategy of leading suppliers; availability of liquid nitrogen, its cost, and ease of application among other considerations. Preferences of customers vary depending on country/region/market factors. Based on these preferences, marketing strategy has to be developed for each country and market segment. Data on various countries were obtained with specific attention to their interest in hybrid cooling systems. Sources for this Information were distributors of BSI equipment in various countries, tender information, conversations with customers, conversations in international exhibitions, as well as information already known in the marketing department of BSI. In addition a special online Questionnaire was prepared and exposed to distributors of BSI and customers. Conclusion was obtained that most likely customers (with readiness to pay) for first launch of hybrid cooling systems are in South Korea, Japan, France and China. Additional target markets that were identified with an expected increase in demand for hybrid cooling systems in next 5 years, are countries with financial resources"
The feasibility study within Phase 1 project showed that there is an increasing market for hybrid cooling systems and there is technical and financial viability to produce such systems in Europe. Technical specification was obtained for such systems that may be used later for prototyping the device. Prototyping is expected to be realized within Phase 2 project being in preparation for application in SME Instrument call.
If such system will be developed, the advantage will be for customers and for BSI. Customers will obtain a product that works autonomously without regular attention. Refilling of LN2 is expected to be no more than once per annum. Additionally, there will be no need to buy and store large amount of LN2 (that is in a case when cooled purely by LN2 systems). BSI will obtain increased profit and will remain as the European leader in producing semiconductor detectors and systems. If there would be no development of hybrid cooling systems within BSI, then the company risks losing its major market and the prestige of its brand as a top producer of radiation detectors.
BSI is in process of launching other products to meet identified customer needs. In all these applications semiconductor detectors are used and cooled. If BSI will launch its hybrid cooling system, then this system will be used as a component across the BSI product line resulting in increased quality and reliability of products, lower total cost and greater customer satisfaction driving increased profits for BSI.
Baltic Scientific Instruments - the developer of semiconductor detectors for X-rays and Gamma-rays