Modification of an Existing Car Shower Tester to Develop 52 Seated Bus Shower Tester at Pragoti Industries Limited.

Abstract

Shower tester booths are used in the automotive industry for leakage tests and to verify the water tightness of fully manufactured and assembled vehicles. By simulating real-world rain conditions, water is sprayed at the vehicle as part of a quality control procedure. Pragoti Industries Ltd. currently has a shower tester booth for testing Cars/SUVs, which will be modified to make it compatible for Bus testing. In the existing Car/SUV shower tester, the shower testing is done by placing the vehicle above 5 bar water pressure, whereas the standard pressure should be maintained between 2-2.5bar in order to avoid the disadvantages of excessive pressure on vehicles. During the modifications for Bus testing, a theoretical issue arose where negative pressure (calculated to be between 2-2.5 bar) could develop. To resolve this, centrifugal pumps will be used to ensure proper water distribution as well as Standard Pressure. The existing Car/SUV shower tester is equipped with flat fan nozzles and primarily use gate valves. In the modified version for Bus testing brass gate valves, glove valves, ball valves, pressure gauges and full cone nozzles will be introduced to improve performance. The transmission pipes in the shower tester booth, with diameters of 1.5, 3, and 5 inches, are crucial as they form the backbone of the water distribution system. Additionally, several pressure gauges will be installed to measure the water pressure within the system, providing real-time data on the force exerted by the water as it flows through pipes, valves, and other equipment. To accommodate the Bus testing, a modified structural design have to be fabricated, using some existing older resources and adding new equipment where necessary. New control and maintenance components need to be installed, and electrical connections have to be checked to ensure proper functionality. Various calculations were performed for both the existing SUV shower tester and the modified Bus shower tester, including flow rate, head loss, power consumption, water pressure, and water consumption. The operating cost for the modified shower tester was calculated to be between 18-22.5 taka (or 0.18-0.22 dollars) for 4-5 minutes of testing. Simulations were conducted using ANSYS for both the older and modified shower testers. These simulations provided valuable insights into the performance variations such as nozzle pressure and pipe flow pressure between the Bus and SUV configurations. For SUV shower tester the simulation showed nozzle pressure around 2 bars. Besides the simulation for Bus shower tester showed the pressure in nozzles around 2.2 bars. These results helped to optimize the shower tester for testing both vehicle types, ensuring structural integrity and operational efficiency under various operating conditions.