Prabhakar, N., Sripathy, P., Bharathiraja, S., and Ayyappan, K., "Theoretical and Experimental Investigation of Flow Rate of Leveling Valve with Filters for Different Operating Angles," SAE Technical Paper 2013-26-0042, 2013, doi:10.4271/2013-26-0042.
Leveling valves are typical pneumatic flow control valves which are fitted in the vehicle chassis to supply or deplete air pressure in the bellows so as to maintain the chassis always in a horizontal position, under the loaded or unloaded condition of vehicle or trailer. Therefore it is necessary to study the flow rate of air for different operating angles of leveling valve corresponding to the vehicle load. Filters are provided, one at the upstream and two at the downstream in order to prevent dust from entering into the valve and bellows. All flow control valves have an inherent flow characteristic that defines the relationship between ‘valve opening’ and flow rate under constant pressure conditions. Hence Computational Fluid Dynamics (CFD) can be utilized as a useful design tool to optimize the flow area of leveling valve and also to study the difference in pressure between upstream and downstream of a filter in order to push the fluid through the filters. This paper covers the optimization of the flow path, flow rate for different opening angles of the leveling valve with and without filters. A thorough CFD analysis with several design iterations of the valve have been made to finalize the flow path with the required flow rate at the outlet to meet the design requirements. The theoretical results are in good agreement with the experiments.