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About: Transom is a(n) research topic. Over the lifetime, 1600 publication(s) have been published within this topic receiving 8919 citation(s).
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01 Nov 1975
Abstract: Recent Davidson Laboratory basic studies of planing hull hydrodynamics have produced a wealth of technology which is not generally available to the small boat design profession. Included are studies related to the pre-planning resistance of transom stern hulls; the effectiveness of trim control flaps; the effect of bottom warp on planing efficiency; the influence of re-entrant transom forms; and the seakeeping of planing hulls. The present paper consolidates these results in a form suitable for design purposes and illustrates their application in predicting planing performance in smooth and rough water.

169 citations

22 Dec 1997
Abstract: A portal apparatus for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow.

87 citations

14 Mar 1985
Abstract: A marine outdrive attachable to the transom of a boat having an inboard engine. The marine outdrive includes a tubular support casing securable to and extendable rearwardly of the boat's transom and having a ball socket at its rear end. The ball socket receives a ball at the front end of a tubular, propeller shaft carrier having a conical outer surface. A drive shaft connectable to the inboard engine is journalled in the support casing. A propeller shaft is journalled in the propeller shaft carrier and has a propeller mounted thereon at the rear end of the propeller shaft carrier. A universal joint couples the two shafts together, the center of such joint substantially coinciding with the point about which the ball pivots within the socket. Hydraulic steering cylinders are attached to the propeller shaft carrier to pivot the latter about a steering axis extending through the pivot point of the ball. A hydraulic trim cylinder extends between the transom and the propeller shaft carrier to swing the propeller shaft carrier about a laterally extending trim axis extending through the pivot point of the ball. The upper end of the trim cylinder is pivotally mounted on the transom at a location above and vertically aligned with the pivot point of the ball or at a location above and forwardly of such pivot point. Improved fins are provided on the propeller shaft carrier near the propeller to stabilize the boat. The drive shaft of the inboard motor can be directly connected to the joint or offset from the joint and coupled thereto by a vertically extending transmission.

78 citations

Journal Article
Abstract: Simulation of the planing hull in waves has been addressed during the last 25 years and basically been approached by strip methods. This work follows that tradition and describes a time-domain strip model for simulation of the planing hull in waves. The actual fluid mechanical problem is simplified through the strip approach. The load distribution acting on the hull is approximated by determining the section load at a number of hull sections, strips. The section-wise 2-dimensional calculations are expressed in terms of added mass coefficients and used in the formulations of both inertia and excitation forces in the equations of motions. The modeling approach starts from the hypothetic assumption that the transient conditions can be modeled based on those section-wise calculations. The equation of motion is solved in the time-domain. The equation is up-dated at each time step and every iteration step with respect to the momentary distribution of section draught and relative incident velocity between the hull and water and catches the characteristic non-linear behavior of the planing craft in waves. The model follows the principles of the pioneering work of E. E. Zarnick differing on model structure and in details such as the modeling of the lift in the transom area. A major part of the work is concerned with experiments and evaluation of simulations with respect to performed model tests and to published experiment data. Simulations of model tests have been performed and comparisons have been made between measured and simulated time series. The link between simulation and experiment is a wave model which is based on a wave height measurement signal. It is developed and evaluated in the thesis. The conclusions are in favor of the 2-dimensional approach to modeling the conditions for the planing hull in waves and among further studies is evaluation of simulated loads and motions to full-scale trial measurement data.

51 citations

Arthur R. Ferguson1Institutions (1)
17 Aug 1981
Abstract: Disclosed herein is a marine propulsion installation comprising a marine propulsion device including a transom bracket having a mounting portion fixed to the rear of a boat transom below the upper edge thereof, and a pair of laterally spaced arms extending upwardly from the mounting portion and including respective upper ends located rearwardly of the boat transom and above the upper edge thereof, a swivel bracket comprising a mounting portion and a pair of laterally spaced arms extending upwardly from the swivel bracket mounting portion and including respective upper ends, a tilt pin connecting the upper ends of the transom bracket and swivel bracket arms to provide for pivotal movement of the swivel bracket relative to the transom bracket about a tilt axis which is horizontally located rearwardly of the transom and above the upper edge thereof, a propulsion unit including an internal combustion engine and a propeller mounted for rotation and driven by the engine, and a king pin connecting the propulsion unit to the swivel bracket mounting portion for pivotal steering movement of the propulsion unit relative to the swivel bracket about a second axis transverse to the tilt axis and for common movement of the propulsion unit with the swivel bracket about the tilt axis and without travel of the propulsion unit over the transom upper edge or into engagement with the transom.

51 citations

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