Sealing Advancements for Rotating Control Devices

Some of the most critical elements of a rotating control device (RCD) are the rotary seals that prevent a pressurized abrasive drilling fluid from destroying the rolling element bearings. The rotary seals prevent the drilling fluid from damaging the bearings by sealing the annular gap between the rotating mandrel and the stationary bearing housing. The combination of pressure causing seal material to bulge into the annular gap and the relative runout between the mandrel and housing can cause extrusion damage of the seal. The relative rotation and runout between the seal and mandrel in an abrasive environment leads to abrasive wear of the seal. Finally, the relatively high surface speed and contact pressure between the seal and mandrel leads to adhesive wear of the seal. When the drilling fluid pressure below the RCD is low there are several suitable rotary seal designs that can provide acceptable RCD life at most rotary drilling speeds. To meet higher speed and pressure conditions for the 100 hour minimum duration, established in API 16RCD, many RCD designs employ a sealing approach that splits the sealing tasks across two seals. One seal excludes the abrasive drilling fluid at low differential pressure and another seal, capable of operating at high differential pressure, retains a clean lubricant that is at nearly the same pressure as the drilling fluid. This sealing system generally requires an external lubricant pressurization system to provide the necessary fluid and pressure environment for the seals. Some drilling sites that operate at these conditions cannot accommodate these large, complex, expensive lubricant systems due to space or access constraints, or economic considerations. This paper describes an innovative sealing system that enables an RCD to operate at 1,500 psi and 100 RPM for 200 hours without requiring an external lubricant pressurization system. This claim is based on extensive laboratory testing of three new technologies included in this sealing system. Key results and summaries from the test program are included in this paper. The three key technologies are: A hydrodynamic spring-loaded lip seal that can be used to exclude abrasive drilling fluid at low-differential pressure or retain a clean lubricant at high differential pressure. A direct-compression hydrodynamic seal that can retain a clean lubricant at high differential pressure. A self-actuating miniature valve that replaces the lubricant supply function of an external lubricant pressurization system.

Containers made of composite materials for transportation and storage of aircraft engines

The description and the main structural components of the design construction of the container made of composite materials are given. There are two options for the container frame — with a composite frame and a metal frame. The use of an inert gas pressurization system of a body is described. The selection of materials for the construction of the container is substantiated, the features and properties of the developed model are considered. Keywords: container, composite materials, transportation, storage, construction. [email protected].

Numerical Simulation of Alternative Smoke Control Approach in a High-Rise Building

Smoke inhalation is a major cause of death in fire accident. Three quarters of building fire casualties were the result of excessive smoke inhalation, even with the presence of a control system. One of the main reasons to a high percentage of fatality is poor circulation and exhaustion of smoke. A proposed system, including an integrated ACMV exhaust with additional louver, will be simulated and compared with the current conventional approach, the fixed pressurization system. The purpose of this study is to determine the effectiveness of the newly proposed approach to smoke exhaustion. Results showed that the path of obscuration for the conventional system in the room displayed a lowered value of 8.77 %, as compared to 9.71% for the integrated ACMV system, due to the greater propagation of smoke out of the room. The results are in agreement as there is a noticeably faster subsiding of hot air temperature at the corridor for the integrated ACMV system than that of the conventional system, after the peak temperature spread of 115 seconds. The current study concluded that the proposed integrated ACMV system with additional louver is more effective for smoke control than the conventional design.

Approach to solution of tank with hydrogen peroxide pressurization by its decomposition products

Aim. To find and confirm the possibility of hydrogen peroxide tank pressurization using high-temperature pressurization gas (~1100К) with a high percentage of steam (up to 70%) without its losses. Research methods. Mathematical modeling of pressurization system parameters with the theory of mass transfer and thermodynamic of variable mass bodies have been used. Results. The conducted research allowed us to find and confirm the possibility of using a new pressurization method with additional sources of heat and elaborate recommendations for its appliance during pressurization time. Scientific novelty. The main processes have been determined, which prevent implementation of the efficient high-temperature pressurization system of the tank with the hydrogen peroxide using peroxide decomposition products. The main obstacle is the volume condensation of vapor in the free volume of the tank when heat exchange processes with boundary surfaces take place. For the first time, by means of theoretical calculations, the expediency and rationality of using the additional sources of heat such as high-temperature combustion product of solid-fuel gas generator based on sodium azide have been proved. Using of this additional source for the first 30 seconds of engine operation has been proved. Practical value. Methodology of pressurization system parameters’ calculation was supplemented with discovered thermodynamic relation, which allowed us to calculate the amount of vapor and take some measures to eliminate the condensation. Results of the research allowed the designation of the pressurization system for the highly concentrated hydrogen peroxide tank with a high value of length to diameter relation with its high-temperature decomposition products.

МЕТОД ОПТИМІЗАЦІЇ ПРИ ПРОЕКТУВАННІ ПОВІТРЯНИХ РОЗПОДІЛЬНИХ МЕРЕЖ ЕНЕРГЕТИЧНИХ СИСТЕМ ЛІТАКА

Augmentation of the flight range, speed and altitude along with the extension of the number of missions accomplished by aircraft has resulted in the expansion and complication of the functions performed by the aircraft air distribution systems. Thus, for instance, the air distribution system of a modern transport airplane includes:- cabin air conditioning system;- underfloor area heating system;- wing ice protection and fuel tank venting system; - engine air intake ice protection system;- engine pneumatic starting system;- the system of controlled air extraction from the equipment/avionics compartment;- hydraulic tank pressurization system;- turbine-driven hydraulic pump drive;- radio equipment and radar pressurization system; - auxiliary power unit compartment heating system;- cabins air conditioning using ground sources;- cabins ventilation using atmospheric air;- air supply for inert gas generation In terms of structure design the aircraft air systems are a complex of heat exchange mechanisms, cooling turbines, compressors, filters, limiters and regulators, mixers, pipelines and other components interacting with each other and with the environment through the exchange of the flows of working media, heat and mechanical energy. The system purpose is implemented in the process of its functioning which implies on-board generation of working medium and its supply to consumers with the quantity and quality of the medium conditioned by external characteristics. External characteristic is a quantification of the purpose of system functioning. As an engineering entity the air distribution systems are characterized by a number of functional indicators. These include the system reliability and weight, expenditure of energy and working medium, overall dimensions, external energy release, factor of safety, cost, etc. In the practical development of air distribution systems, when meeting the cooling performance requirements use is later made, as a general rule, of such indicator as "installation weight", less frequently – of the integrated "reduced" weight indicator with introduction of limitations on other indicators. Designing the air distribution systems involves lookup for a compromise between a number of conflicting requirements: minimization of the installation weight and energy losses, high system reliability, fail safety, rigorous geometric constraints, high manufacturability and comparatively low cost of production. Application of the mathematical statics techniques makes it possible to optimize parameters of the air system.