PROSPECTS IN MOTOR CAR COMPACT LOADING IN RAILROAD CARS

Motor car competitiveness in markets distant from motor car manufacturing area depends on the value of logistics outgoings. A motor car compact loading in special railroad cars allows reducing considerably outgoings mentioned. According to a common loading order a railroad car capacity within the limits of extreme dimensions throughout the height is not completely used as it exceeds considerably a total height of two motor cars. In this connection it is possible to compact a loading layout only through the location of a motor car rear part of a front motor car under the engine jacket of it following motor car at their inclined fixation and longitudinal orientation. It allows stowing additionally two motor cars in every railroad car. The motor cars of some models cannot be stowed in two rows in one deck. It is caused with that a total width of two motor cars exceeds extreme dimensions of a railroad car allowed for railway operations. The problem could be solved, if motor car loading in every deck is carried out on load floorings the surfaces of which have a tilt from the center of a railroad car to its side walls. At the inclination of about 100 the projection on a horizontal plane of maximum cross dimension of a motor car on a level of passenger seats decreases by 25 mm. Space saving makes 50 mm on two parallel rows. As a result a two-row rail freightage of motor cars becomes possible in every motor car deck with the width 1680 mm common for products of Volzhsky Motor Car Works. At the expense of this way a length of haul economically feasible increases considerably.

Refrigerated Railroad Car Design for Shipping Frozen Meat Using Alternative Refrigerants

Refrigerated railroad cars, known as reefers, are railroad rolling stock designed to carry perishable freight at specific temperatures. They are insulated boxcars that keep the cargo at a regulated temperature. As soon as railroad cars had the capability to keep a load cold, the potential growth of the meat, dairy, fruit and brewery industries became nearly unlimited. In this paper, a cold-room system in a railroad car was investigated as a case study to illustrate the use of the sample model. The change of substitute refrigerants and insulation thickness of the cold rooms’ refrigeration system was also considered in the model. The coefficient of performance (COP), refrigerant flow rate and capacities of each component of the refrigeration system were calculated for the refrigerants R12, R22, R134a, R290, R410A, R430A, R431A, R436A, R507A, R600a as part of this analysis. As a result of the energy analyses, all of the substitute refrigerants have a slightly lower COP and require higher compressor work than R12 and R22 for a condensation temperature of 40°C. The frozen meats have an evaporation temperature of −25°C related to the preserved product in the case studies. Influences of the insulation thickness of the wall on evaporator capacity and outside temperature of various cities on the condenser are also studied.